Plasma Β-endorphin Research Articles

Perioperative Transcutaneous Electrical Acupoint Stimulation Reduces Postoperative Pain in Patients Undergoing Thoracoscopic Surgery: A Randomized Controlled Trial.

This study aimed to determine the effects of perioperative transcutaneous electrical acupoint stimulation (TEAS) on postoperative pain management in patients undergoing thoracic surgery. In the prospective, randomized, controlled study, a total of 84 patients undergoing video-assisted thoracoscopic surgery (VATS) were randomly allocated to the TEAS group (Group T) or control group (Group C). Patients in the Group T received TEAS at Neiguan (PC6) and Hegu (LI4) acupoints for 30 min before anesthesia induction and 30 min after thoracoscopic surgery. Patients in the Group C received the same placement of electrodes but without electrical stimulation. The numeric rating scale (NRS) pain score, remifentanil consumption, demand for rescue analgesics and incidence of postoperative nausea and vomiting (PONV), patient satisfaction, and the levels of plasma β-endorphin (EP) and IL-6 were recorded. Patients in the Group T had significantly lower NRS pain scores at 6 h, 12 h, 24 h, and 48 h after surgery than those in the Group C. Compared with Group C, patients in Group T had lower remifentanil consumption during operation, lower demand for rescue analgesics and lower rate of PONV within 24 h after surgery. Patients in Group T also had lower IL-6 content, higher β-EP content and higher satisfaction degree than those in the Group C. Perioperative TEAS significantly decreased postoperative pain and rescued analgesia requirements and the incidence of PONV in patients undergoing thoracoscopic surgery, with a higher patient satisfaction. This trial is registered with ChiCTR2100051841.

Acute Low Dose Naltrexone Increases β-Endorphin and Promotes Neuronal Recovery Following Hypoxia-Ischemic Stroke in Type-2 Diabetic Mice.

Diabetic patients experience significant mortality and poor recovery following ischemic stroke. Our clinical and basic science studies demonstrate an overall immune suppression in the periphery of diabetic stroke patients, as well as within the central nervous system (CNS) of type-2 diabetic mice following hypoxia-ischemia (HI). Low doses of naltrexone (LDN) improved clinical outcomes in many autoimmune diseases by acting on opioid receptors to release β-endorphin which in turn balances inflammatory cytokines and modulates the opioid growth factor (OGF)-opioid growth factor receptor (OGFr) pathway. We hypothesized that in our model of diabetic mice, LDN treatment will induce the release of β-endorphin and improve CNS response by promoting neuronal recovery post HI. To test this hypothesis, we induced HI in 10week old male db/db and db/ + mice, collected tissue at 24 and 72h post HI, and measured OGF levels in plasma and brain tissue. The infarct size and number of OGF + neurons in the motor cortex, caudate and hippocampus (CA3) were measured. Following HI, db/db mice had significant increases in brain OGF expression, increased infarct size and neurological deficits, and loss of OGFr + neurons in several different brain regions. In the second experiment, we injected LDN (1mg/kg) intraperitoneally into db/db and db/ + mice at 4, 24, and 48h post HI, and collected brain tissue and blood at 72h. Acute LDN treatment increased β-endorphin and OGF levels in plasma and promoted neuronal recovery in db/db mice compared to phosphate buffer saline (PBS)-treated diabetic mice suggesting a protective or regenerative effect of LDN.

β-Endorphin mediates radiation therapy fatigue.

Fatigue is a common adverse effect of external beam radiation therapy in cancer patients. Mechanisms causing radiation fatigue remain unclear, although linkage to skin irradiation has been suggested. β-Endorphin, an endogenous opioid, is synthesized in skin following genotoxic ultraviolet irradiation and acts systemically, producing addiction. Exogenous opiates with the same receptor activity as β-endorphin can cause fatigue. Using rodent models of radiation therapy, exposing tails and sparing vital organs, we tested whether skin-derived β-endorphin contributes to radiation-induced fatigue. Over a 6-week radiation regimen, plasma β-endorphin increased in rats, paralleled by opiate phenotypes (elevated pain thresholds, Straub tail) and fatigue-like behavior, which was reversed in animals treated by the opiate antagonist naloxone. Mechanistically, all these phenotypes were blocked by opiate antagonist treatment and were undetected in either β-endorphin knockout mice or mice lacking keratinocyte p53 expression. These findings implicate skin-derived β-endorphin in systemic effects of radiation therapy. Opioid antagonism may warrant testing in humans as treatment or prevention of radiation-induced fatigue.

Neuroendocrine effects of a single bout of functional and core stabilization training in women with chronic nonspecific low back pain: A crossover study.

Exercise‐induced hypoalgesia (EIH) is characterized as the pain reduction after an exercise session and it seems to be related to the release of plasma β‐endorphin. In this sense, the core stabilization training (CT) has been suggested for patients with chronic nonspecific low back pain (CNSLBP), but it is unclear whether it induces EIH. Patients with CNSLBP have neuromotor dysfunctions that can affect the performance of functional tasks, thus, performing functional training (FT) could improve motor control and promote EIH, since functional training uses multi‐joint exercises that aim to improve the functionality of actions performed in daily life. EIH is usually assessed using quantitative sensory tests (QST) such as conditioned pain modulation, pressure pain threshold, and temporal summation. Thus, the sum of parameters from quantitative sensory tests and plasma β‐endorphin would make it possible to understand what the neuroendocrine effects of FT and CT session are. Our study compared the acute effect of CT and FT on the EIH and plasma β‐endorphin release, and correlated plasma β‐endorphin with quantitative sensory testing in patients with CNSLBP. Eighteen women performed two training sessions (CT and FT) with an interval of 48 h between sessions. EIH was assessed by QST and plasma β‐endorphin levels. Results showed that only FT significantly increased plasma β‐endorphin (FT p < 0.01; CT p = 0.45), which correlated with pain pressure threshold (PPT) and conditioned pain modulation (CPM). However, QST values were not different in women with CNSLBP after CT or FT protocols. Plasma β‐endorphin correlated with PPT and CPM, however, the same did not occur with a temporal summation.

The effects of conventional, warm and cold acupressure on the pain perceptions and beta-endorphin plasma levels of primiparous women in labor: A randomized controlled trial

ObjectiveThis study was performed to determine the impact of different acupressure procedures, performed on women's hands during labor, on β-endorphin plasma levels and labor pain perception. DesignRandomized controlled experimental trial Setting and ParticipantsThis study was conducted with 140 pregnant women in the delivery rooms of a university research and training hospital and a state hospital in a province in the Black Sea Region of Turkey. MethodsThis study was conducted with three experimental groups (who had conventional, warm and cold acupressure on their LI4 acupressure point) and one control group (no acupressure). Each group included 35 pregnant women. The data were collected using a personal information form, the Labor Intervention Follow-up Form, the Visual Analog Scale (VAS) and the Verbal Category Scale (VCS). Its main outcomes were the women's labor pain perceptions and β-endorphin plasma levels. ResultsThe experimental and control groups had homogeneous introductory characteristics. The experimental groups had significantly higher mean VAS and VCS posttest scores than the control group (p<0.001). The experimental groups’ mean posttest β-endorphin plasma levels were also significantly higher (p<0.05). ConclusionIn this study, conventional, warm and cold acupressure reduced the women's labor pain and increased their β-endorphin plasma levels. Midwives can use acupressure to reduce labor pain.

Anxiety enhances pain in a model of osteoarthritis and is associated with altered endogenous opioid function and reduced opioid analgesia.

Negative affect, including anxiety and depression, is prevalent in chronic pain states such as osteoarthritis (OA) and associated with greater use of opioid analgesics, potentially contributing to present and future opioid crises. We tested the hypothesis that the interaction between anxiety, chronic pain, and opioid use results from altered endogenous opioid function. A genetic model of negative affect, the Wistar-Kyoto (WKY) rat, was combined with intra-articular injection of monosodium iodoacetate (MIA; 1 mg) to mimic clinical presentation. Effects of systemic morphine (0.5-3.5 mg·kg-1) on pain behaviour and spinal nociceptive neuronal activity were compared in WKY and normo-anxiety Wistar rats 3 weeks after MIA injection. Endogenous opioid function was probed by the blockade of opioid receptors (0.1-1 mg·kg-1 systemic naloxone), quantification of plasma β-endorphin, and expression and phosphorylation of spinal mu-opioid receptor (MOR). Monosodium iodoacetate-treated WKY rats had enhanced OA-like pain, blunted morphine-induced analgesia, and greater mechanical hypersensitivity following systemic naloxone, compared with Wistar rats, and elevated plasma β-endorphin levels compared with saline-treated WKY controls. Increased MOR phosphorylation at the master site (serine residue 375) in the spinal cord dorsal horn of WKY rats with OA-like pain (P = 0.0312) indicated greater MOR desensitization. Reduced clinical analgesic efficacy of morphine was recapitulated in a model of high anxiety and OA-like pain, in which endogenous opioid tone was altered, and MOR function attenuated, in the absence of previous exogenous opioid ligand exposure. These findings shed new light on the mechanisms underlying the increased opioid analgesic use in high anxiety patients with chronic pain.

How do Spinal Stabilization Exercises Relieve Back Pain? An Analysis of Potential Mechanisms of Analgesia Effected at Muscular, Spinal Cord and Supraspinal Levels

STUDY OBJECTIVE Spinal stabilization exercises have emerged as an effective treatment for low back pain (LBP), but the mechanism of analgesia obtained through these exercises is unknown. The objective of the present research was to derive viable hypotheses for this pain relief based on previously validated analgesic mechanisms. METHODS A literature review was conducted by first considering commonly known methods of both exogenous and endogenous pain control, and then selecting for deeper analysis those mechanisms which could conceivably be operative during the self-generated, low amplitude movements involved in spinal stabilization exercises. The three chosen analgesic processes were related to perfusion, gate control, and endogenous analgesia. RESULTS Mechanism 1: Increased Perfusion Muscle contraction is known to increase perfusion of muscle tissue, leading to increased nutrient delivery and removal of waste products, and ischemia caused by atherosclerosis causes pain in multiple tissues including muscle. The lumbar blood supply derives from the abdominal aorta/lumbar artery system and blockages in this system have been linked to LBP. Gentle stabilization exercises targeting the core which activate these muscles may thus increase perfusion and thereby lessen pain related to ischemia. Mechanism 2: Gate Control-Mediated Analgesia Since Melzack and Wall first proposed the Gate Control Theory, the existence of multiple specific pain-inhibiting circuits linking dorsal horn laminae has been confirmed. Recent studies support a role for muscle spindles and golgi tendon organs in “closing the gate” to pain sensations, via muscle contraction. Pain relief during contract-relax and resistance exercises has been achieved in at least 3 studies, possibly through activation of these receptors. This process may explain in part the achievement of pain relief obtained after a short course of spinal stabilization exercises. Mechanism 3: Exercise-Induced Analgesia Exercise Induced analgesia (EIA) works through multiple endogenous systems that decrease pain perception, including the opioidergic, serotonergic, noradrenergic, endocannabinoid, and nitrergic systems. Numerous studies have shown EIA occurs with aerobic exercise in both humans and animals. The role of EIA in analgesia during isometric and core stabilization exercises is starting to be explored, including findings that both plasma β-endorphin and serotonin levels increase after core exercises. CONCLUSIONS The manner in which spinal stabilization exercises achieve analgesia is unknown. The vascular, gate-control, and exercise-mediated mechanisms outlined above are known to elicit an analgesic effect, and could conceivably be evoked by the gentle, low amplitude movements of these exercises. Rigorous, prospective research on perfusion of the muscles involved in core stabilization, the activation of muscle proprioceptive pathways in dorsal horn pain synapses, and plasma levels of key hormones during and after core stabilization exercises, would help support or refute the existence of this link.

Endogenous Opioid Levels Do Not Correlate With Itch Intensity and Therapeutic Interventions in Hepatic Pruritus.

Background: Chronic pruritus affects up to 70% of patients with immune-mediated hepatobiliary disorders. Antagonists of the μ-opioid receptor (MOR) and agonists of the κ-opioid receptor (KOR) are used to treat hepatic itch, albeit with limited success. An imbalance between ligands of MOR and KOR receptors has recently been suggested as a potential mechanism of hepatic pruritus. In this study, we therefore investigated systemic levels of important endogenous opioids such as β-endorphin, dynorphin A, Leu- and Met-enkephalin in plasma of a large cohort of well-characterized patients with immune-mediated cholestatic disorders, including patients with liver cirrhosis, and during effective anti-pruritic therapy.Methods: Plasma samples and clinical data were prospectively collected from well-characterized patients with primary/secondary sclerosing cholangitis (PSC/SSC), primary biliary cholangitis (PBC) and overlap syndromes suffering from pruritus (n = 29) and age-, gender- and disease-matched controls without pruritus (n = 27) as well as healthy controls (n = 20). General laboratory testing for hepatobiliary and renal function was performed. Levels of β-endorphin, dynorphin A, Leu- and Met-enkephalin were quantified in plasma by ELISA. Intensity of pruritus over the last week was evaluated using a visual analog scale (VAS, 0–10).Results: PBC and PSC patients with or without pruritus did neither differ in disease entity, disease stage, nor in the presence of cirrhosis. While both dynorphin A and β-endorphin concentrations were lower in pruritic patients compared to those without pruritus and healthy controls, the MOR/KOR ligand ratio was unaltered. No significant differences were observed for Leu- and Met-enkephalin concentrations. Opioid levels correlated with neither itch intensity nor stage of disease. Cirrhotic patients displayed higher concentrations of MOR agonist Leu-enkephalin and KOR agonist dynorphin A. Endogenous opioid levels remained largely unchanged after successful treatment with the potent anti-pruritic drugs rifampicin and bezafibrate.Conclusions: Endogenous opioid levels and the MOR/KOR ligand ratio neither correlate with itch intensity nor differentiate pruritic from non-pruritic patients with immune-mediated liver diseases. Thus, endogenous opioids may modulate signaling pathways involved in hepatic pruritus, but are unlikely to represent the major pruritogens in liver disease.

Beta-endorphin inhibits the inflammatory response of bovine endometrial cells through δ opioid receptor in vitro

Postpartum uterine infections are common reproductive diseases in postpartum cows. Evidence has shown that plasma β-endorphins increase during bovine uterine inflammation. However, the effect of β-endorphins on the inflammatory response in bovine endometrium has not been clarified. The aim of this study was to investigate the effect of β-endorphins on the inflammatory response of bovine endometrial epithelial and stromal cells, and to explore the possible mechanism. The cells were treated with E. coli lipopolysaccharide (LPS) to simulate inflammation, which was characterized by the significant activation of NF-κB signaling pathway and the increased gene expression of the downstream proinflammatory cytokines (approximately 1.2- to 15-fold increase, P < 0.05). By using Western blot and qPCR techniques, we found that β-endorphins inhibited the key protein expression of NF-κB pathway, and the gene expressions of TNF, IL1B, IL6, CXCL8, nitric oxide synthase 2, and prostaglandin-endoperoxide synthase 2 (P < 0.05). The co-treatment of β-endorphins and opioid antagonists showed that the anti-inflammatory effect of β-endorphins could be blocked (P < 0.05) by non-selective opioid antagonist naloxone or δ opioid receptor antagonist ICI 154129, but not the μ opioid receptor antagonist CTAP (P > 0.05). In conclusion, β-endorphins may inhibit the inflammatory response of bovine endometrial epithelial and stromal cells through δ opioid receptor.

Cannabinoid Receptor-2 Activation in Keratinocytes Contributes to Elevated Peripheral β-Endorphin Levels in Patients With Obstructive Jaundice.

Cholestatic diseases are often accompanied by elevated plasma levels of endogenous opioid peptides, but it is still unclear whether central or peripheral mechanisms are involved in this process, and little is known about the change of pain threshold in these patients. The purpose of this study was to determine the preoperative pain threshold, postoperative morphine consumption, and central and peripheral β-endorphin levels in patients with obstructive jaundice. This study also tests the hypothesis that activation of the cannabinoid receptor-2 (CB2R) in skin keratinocytes by endocannabinoids is the mechanism underlying circulating β-endorphin elevation in patients with obstructive jaundice. The electrical pain thresholds, 48-hour postoperative morphine consumption, concentrations of β-endorphin in plasma and cerebrospinal fluid, skin and liver β-endorphin expression, and plasma levels of endocannabinoids were measured in jaundiced (n = 32) and control (n = 32) patients. Male Sprague-Dawley rats and human keratinocytes (human immortalized keratinocyte cell line [HaCaT]) were used for the in vivo and in vitro experiments, respectively. Mechanical and thermal withdrawal latency, plasma level, and skin expression of β-endorphin were measured in CB2R-antagonist-treated and control bile duct-ligated (BDL) rats. In cultured keratinocytes, the effect of CB2R agonist AM1241-induced β-endorphin expression was observed and the phosphorylation of extracellular-regulated protein kinases 1/2, p38, and signal transducer and activator of transcription (STAT) pathways were investigated. This study found (1) the plasma level of β-endorphin (mean ± standard error of the mean [SEM]) was 193.9 ± 9.6 pg/mL in control patients, while it was significantly increased in jaundiced patients (286.6 ± 14.5 pg/mL); (2) the electrical pain perception threshold and the electrical pain tolerance threshold were higher in patients with obstructive jaundice compared with controls, while the 48-hour postoperative morphine consumption was lower in the jaundiced patients; (3) there was no correlation between plasma β-endorphin levels, electrical pain thresholds, and 48-hour postoperative morphine consumption in patients with obstructive jaundice; (4) the plasma level of the endogenous cannabinoid anandamide was increased in the jaundiced patients; (5) CB2R antagonist treatment of the BDL rats reduced β-endorphin levels in plasma and skin keratinocytes, while it did not alter the nociceptive thresholds in BDL and control rats; (6) the endocannabinoid anandamide-induced β-endorphin synthesis and release via CB2R in cultured keratinocytes; and (7) phosphorylation of extracellular-regulated protein kinases 1/2 is involved in the CB2R-agonist-induced β-endorphin expression in keratinocytes. CB2R activation in keratinocytes by the endocannabinoid anandamide may play an important role in the peripheral elevation of β-endorphin during obstructive jaundice.

The Relationship Between Antipsychotic Treatment and Plasma β-Endorphin Concentration in Patients with Schizophrenia.

ObjectiveSome studies indicate the presence of elevated opioid levels in cases of schizophrenia and their relationship with negative symptoms. The pathogenesis of schizophrenia may be associated with an imbalance in the modulatory effect of opioids on the dopaminergic system. The aim of the study was to identify the association between β-endorphin (BE) concentration and the outcome of short-term schizophrenia treatment.MethodsWe examined 49 patients hospitalized due to exacerbation of schizophrenia symptoms and 47 controls without schizophrenia. The severity of psychopathological symptoms was evaluated using Positive and Negative Syndrome Scale (PANSS) at the onset of hospitalization, and after four, six and ten weeks of treatment. Patients were classified into negative (NEG) and mixed (M) psychopathological subtypes according to the PANSS composite index. Β-endorphin (BE) plasma concentrations were assessed in all participants; in patients on inclusion to the study and after six weeks of treatment.ResultsThe patients with schizophrenia demonstrated higher BE levels than controls. During six-week antipsychotic treatment, BE concentration significantly increased in both NEG (p=0.000) and M (p=0.007), and positive symptoms were effectively reduced. In the NEG group, the prevalence of negative symptoms decreased only transiently and returned to approximately baseline values after 10 weeks (p=0.268). In the M patients, the prevalence of negative symptoms increased gradually (p=0.001), with more severe positive and, notably, negative symptoms correlating with higher BE2 concentrations at the 10-week assessment (R= 0.47, p= 0.0135 vs R= 0.74, p=0.0000). In both NEG and M, a greater rise in BE2 level correlated with a lower composite index during treatment.ConclusionPatients with schizophrenia demonstrate higher BE levels compared to controls. These changes in BE concentration during antipsychotic treatment could reflect the interaction between dopaminergic transmission and endogenous opioids. A rise in BE level following effective antipsychotic therapy could be a potential predictor of persisting negative symptoms.

Safety and Efficacy of Ultrasound-Guided Retrolaminar Block of Multiple Injections in Retroperitoneal Laparoscopic Nephrectomy: A Prospective Randomized Controlled Study

PurposeUltrasound-guided retrolaminar block (RLB) has the potential to provide postoperative analgesia in retroperitoneal laparoscopic surgery. This study was conducted to evaluate the effects of RLB when compared with local infiltration analgesia (LIA) in retroperitoneal laparoscopic nephrectomy.Patients and MethodsOne hundred and fifteen patients scheduled for laparoscopic nephrectomy were divided into two groups: the RLB group (n = 57) received an ultrasound-guided RLB, while the LIA group (n = 58) received LIA. At 2, 4, 6, 24, and 48 hours after operation, the maximal visual analog score (VAS), sufentanil and rescue analgesia consumption, and the utilization of patient-controlled intravenous analgesia (PCIA) were assessed. The incidence rates of postoperative nausea and vomiting (PONV); time of leaving bed (at the first instance); and the levels of plasma β-Endorphin (β-EP), Interleukin-1β (IL-1β), and prostaglandin E2 (PEG2) 30 min after extubation were noted.ResultsPatients in the RLB group had significantly lower VAS scores; lower sufentanil cumulative consumption; lower manual addition frequency of PCIA; lower proportion of using rescue analgesia within 48 hours after operation; lower incidence rate of PONV; shorter resuscitation times; earlier time of leaving the bed; and lower β-EP, IL-1 β, and PEG2 levels.ConclusionUltrasound-guided RLB of multiple injections is both safe and controllable for postoperative analgesia after retroperitoneal laparoscopic nephrectomy. When compared with LIA, RLB has better and longer-lasting analgesic effect, lower incidence rates of PONV, and the potential to reduce the level of postoperative inflammatory factors.Trial RegistrationChina Clinical Trials Registration Center (http://www.chictr.org.cn, No. ChiCTR1800017526, Date of registration: 2018–08-02).

The Analgesic Effect of Transcutaneous Electrical Acupoint Stimulation on Labor: A Randomized Control Study.

ObjectiveThis study aimed to investigate the analgesic effect of transcutaneous electrical acupoint stimulation (TEAS) on labor.MethodsPrimiparas with single birth and head presentation were enrolled in this study and randomly divided into three groups: TEAS group (n = 76), patient-controlled epidural analgesia (PCEA) group (n = 75), and control group without any analgesic measures (n = 78).ResultsCompared with the control group, the visual analog scores of the TEAS group and the PCEA group at each time point decreased (P < 0.01). The decrease was greater in the PCEA group than that in the TEAS group (P < 0.01). At 120 minutes after analgesia, there were significant differences in plasma β-endorphin content between the TEAS group, PCEA group, and control group (P < 0.01). The difference between the PCEA group and the control group was statistically significant (P < 0.01). Among the parturients having a vaginal delivery, the duration of the first stage of labor was significantly shorter in the TEAS group and control group than in the PCEA group (P < 0.01). The duration of the second stage of labor was significantly shorter in the TEAS group than in the PCEA group (P < 0.01). Oxytocin usage rate during labor was significantly lower in the TEAS group and control group than in the PCEA group (P < 0.01), and adverse reactions were significantly fewer in the TEAS group and control group than in the PCEA group (P < 0.01).ConclusionThe duration of the first and second stage of labor is significantly shorter in the TEAS group than in the PCEA group. TEAS does not increase the use rate of oxytocin or the rate of cesarean section and will not bring about obvious maternal or fetal adverse reactions.

WITHDRAWN: The Effect of Electroacupuncture Therapy on Pain, Plasma β-Endorphin, and Quality of Life of Stage III Cervical Cancer Patients: A Randomized Control Trial

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Plasma β-Endorphin Concentration and Antipsychotic Treatment Outcome in Schizophrenia: 1-Year Follow-Up.

BackgroundIncreased levels of endogenous opioids have been observed in patients with schizophrenia; however, the influence of these endogenous opioids on the biology of schizophrenia remains unclear. The aim of this study was to evaluate the impact of beta-endorphin (BE) on the course of schizophrenia and risk of relapse.Material/MethodsThe study included 25 patients hospitalized with schizophrenia and 47 controls. Their symptoms were evaluated using Positive and Negative Syndrome Scale (PANSS) and composite index at five points: at the onset of hospitalization; after 4, 6 and 10 weeks of treatment; and after 12 months. β-endorphin plasma concentrations were assessed in patients at study enrollment and after 6 weeks of treatment. Data regarding rehospitalization during follow-up were also collected.ResultsPatients had higher BE concentration than controls at study enrollment (P=0.002) and after 6 weeks (P=0.000). BE levels increased during treatment (mean 0.538ng/mL vs. mean 0.624 ng/mL; P=0.007). No correlation was found between BE concentration and PANSS subscale score at any stage of the study. A higher BE level at study enrollment was related to a predominance of negative symptoms after 1 year, measured with composite index (R=−0.404; P=0.045). Patients who were later hospitalized again were significantly more likely to demonstrate an increase in BE levels over 6 weeks (P=0.001).ConclusionsIndividuals with schizophrenia demonstrated higher BE concentrations than healthy controls; this tendency was particularly apparent in those affected by negative symptoms. The imbalance in the endogenous opioid system might adversely alter the course of disease and predispose patients to persistence of negative symptoms, despite antipsychotic treatment.

Effects Of Exercise On Plasma β-endorphin And Dsq In Methamphetamine Dependent Individuals

PURPOSE: Methamphetamine is the main component of opioid drugs, which directly affects the central nervous system which leading to abnormal secretion of catecholamines.Physical exercise has been shown to benefit diverse medical and behavioral conditions. This study assesses the feasibility and efficacy of an 8-week aerobics and resistance training program on β-endorphin in plasma and desire for speed questionnaire(DSQ) for methamphetamine (MA) dependence. METHODS: A total of 60 MA-dependent individuals were randomized to aerobics exercise group (AE, n=30) and resistance exercise group (RE, n=30). Each training group was trained over 8weeks, 3 times/week, 90minutes each time, which include formal training (70 minutes), warm-up (10 minutes) and recovery (10 minutes). The aerobic exercise intensity is 65%-85% HRmax and the muscle strength by 1-repetition maximum (1-RM) and endurance at 85% in resistant exercise group. RESULTS: (1) After 8 weeks of exercise intervention, the β-endorphin levels in the group AE and group RE were significantly increased (p<0.01). Inside, the level of β-endorphin in the group AE was increased from 154.7 pg/ml to 214.3 pg/ml, the rate of change of β-endorphin in plasma was 39.24%. The level of β-endorphin in the high-intensity group was increased from 158.4 pg/ml to 181.7 pg/ml, the rate of change was 14.76%. It is suggested that the effect of aerobic exercise on plasma β-endorphin is more effective than that of resistance exercise.(2) After 8 weeks of exercise intervention, MA-dependent have reduced their desires, The score of the DSQ in t both group were significantly decreased (p<0.05). In the group AE the score was decreased from 105.40 to 75, and the score of the group RE was decreased from 111.4 to 77.7. CONCLUSIONS: Both aerobic and resistance exercise can increase the level of β-endorphin in MA-dependent individuals, promote the formation of euphoria compensation mechanism, and reduce the desire for speed. The effect of aerobic exercise on plasma β-endorphin in methamphetamine dependent individuals was more obvious.

Plasma B-endorphin and cortisol profiles around periparturient period in Friesian Cattle suffering from reproductive disorders in Egypt

The present study aimed to determine plasma β-endorphin and cortisol concentrations in cattle with reproductive disorders (dystocia and retained placenta) and weakness body condition score during periparturient period. Stress may cause an overproduction of beta-endorphins and free radicals. Twenty multiparous Friesian cows weighing 400–650 kg aged 6-10 years and between (3-8) parities at late pregnancy period was used for two months before parturition. From ten days before the expected birth date the birth canal of each animal was monitored by rectal and vaginal palpations, and the body temperature was checked daily to predict the probable time of parturition. Animals were divided into four groups according to parturition disorders’ five animals in each one. First group delivered spontaneously at term with no obstetrical assistance(A), second group delivery was at term but was accompanied by dystocia(B), third group delivery was at term but was accompanied by retained placenta(C), and fourth group delivery was at term but animals showed weakness body condition score (D). Results illustrated that Plasma β-endorphin level in Friesian cattle during pregnancy state increased gradually through gestation period. It reaches its highest level during the third trimester due to stressful state. Also, it reaches its peak at zero time of parturition by appearing its analgesic action. Meanwhile, it decreases gradually towards re-establishment of ovarian cycle. Generally, cows suffering reproductive disorders had a clear impact on blood plasma β-endorphin concentration around parturition process.

The efficacy of bilateral sphenopalatine ganglion block under general anesthesia in trans-sphenoidal endoscopic hypophysectomy

Background:The most important goal in endoscopic pituitary surgery is bloodless field with better visualization under hemodynamic stability and good analgesia to improve the outcome, the current study was performed to evaluate the intraoperative anesthetic and postoperative analgesic effects of bilateral sphenopalatine ganglion block(SPGB)as adjuvant to general anesthesia in endoscopic transsphenoidal resection of pituitary adenoma. Patients and methods:thirty patients(ASA I-II)aged 22–55 years, randomly assigned into two equal groups. After stabilization of general anesthesia, the patients received bilateral sphenopalatine ganglion block with 2ml of either2% lidocaine: 1:200000 epinephrine(SPGB group)or sterile normal saline(control group). Mean arterial blood pressure was maintained at 60–70mmHg by using nitroglycerine. Intraoperative MAP and heart rate, Nitroglycerine and propranolol consumption, blood loss, average category scale, emergence time were recorded. Also, pre and postoperative plasma B-endorphin, VAS and time of first request for analgesia, total dose of meperidine consumption in the first 24hours postoperatively, patient’s satisfaction and post-operative complication were recorded. Results: Sphenopalatine ganglion block group showed decrease in blood loss(P<0.001), ACS(P<0.01), nitroglycerine consumption(P<0.0001)and emergence time(P< 0.001). At PACU, visual analogue pain score were lower in SPGB at 0,1,6(P<0.001), there were a high difference between two groups in B-endorphin levels(P<0.001)and also in dose of meperidine, % of patients needs analgesia and patients satisfaction(P<0.002), Conclusion:Use of sphenopalatine ganglion block with general anesthesia is a safe and effective technique, it contributes in adequate intra and postoperative analgesia needed for stabilization of hemodynamics with less blood loss, improving the quality of surgical field instead of controlled hypotensive technique during endoscopic endo-nasal trans-sphenoidal hypophysectomy.

The Relationship Between Course of Illness and β-Endorphin Plasma Levels in Patients with Schizophrenia.

ObjectiveExtensive investigations have been conducted into predictors of schizophrenia outcome. The heterogeneity of the illness implies that many factors should be taken into account. Some studies have reported the relationship between increased β-endorphin concentration and predominant negative symptoms.MethodsWe included 77 outpatients with schizophrenia and 74 healthy controls. Data referring to duration and course of illness, hospitalization number and treatment were collected on the basis of clinical interviews and medical documentation analysis. The β-endorphin concentrations were assessed once in all participants, at the onset of the study.ResultsA chronic course of illness was found in 44 of the 77 schizophrenics. Patients with schizophrenia, especially those with a chronic course of illness, revealed significantly higher β-endorphin concentrations than those with an episodic course and controls (mean 29.70 vs 19.86 pmol/L; p=0.0001). Increased levels of β-endorphin were related to longer duration of illness (R=0.294, p=0.009) and frequent psychiatric hospitalization (R=0.346, p=–0.002).ConclusionEndorphins may be potential biological predictors of persistent negative symptoms and final outcome in schizophrenia.

Cough Suppression during Flexible Bronchoscopy Using Transcutaneous Electric Acupoint Stimulation: A Randomized Controlled Study.

Background and Objective. Transcutaneous electric acupoint stimulation (TEAS) is recommended for its sedative and analgesic effects. We sought to evaluate the effect of TEAS on cough suppression during flexible bronchoscopy (FB) and explore the underlying mechanism. Methods. In this single-center, randomized, single-blind, parallel-controlled study, we randomized 100 patients scheduled for FB into two equal groups treated with or without TEAS (TEAS group and control group). Patients in the TEAS group received 30 min of stimulation at the Hegu (LI4), Neiguan (PC6), and Lieque (LU7) points before FB. The control group underwent the same procedure, but without stimulation. The primary outcome was the intraoperative cough score determined by the bronchoscopist. The secondary outcomes were patient-reported discomfort scores and other procedural parameters. Results. Compared with the controls, patients who received TEAS preconditioning had lower cough scores (P=0.0027) and requirement of lidocaine and fentanyl (P < 0.05) and significantly higher postprocedural plasma β-endorphin levels (P=0.0367). There were no intergroup differences in discomfort scores, midazolam dosage, rate of premature termination, oxygen requirement, sedation level, airway assistance, oxygen saturation, lowest oxygen saturation level, heart rate, plasma substance-P levels, and rate of complications after 24 h. The total procedure duration, time for passage of the bronchoscope through the vocal cords, and systolic and diastolic blood pressure levels were less in the TEAS group than in the control group (P=0.033, 0.039 and <0.05, respectively). Conclusion. The combination of midazolam and TEAS was superior to midazolam alone for cough suppression during FB, probably due to increased plasma β-endorphin levels. This trial is registered with ChiCTR1800016612 at chictr.org.cn/index.aspx.