Different Concentrations Of Epinephrine Research Articles

Exercise accelerates recruitment of CD8+ T cell to promotes anti-tumor immunity in lung cancer via epinephrine

Background and purposeIn recent years, there has been extensive research on the role of exercise as an adjunctive therapy for cancer. However, the potential mechanisms underlying the anti-tumor therapy of exercise in lung cancer remain to be fully elucidated. As such, our study aims to confirm whether exercise-induced elevation of epinephrine can accelerate CD8+ T cell recruitment through modulation of chemokines and thus ultimately inhibit tumor progression.MethodC57BL/6 mice were subcutaneously inoculated with Lewis lung cancer cells (LLCs) to establish a subcutaneous tumor model. The tumor mice were randomly divided into different groups to performed a moderate-intensity exercise program on a treadmill for 5 consecutive days a week, 45 min a day. The blood samples and tumor tissues were collected after exercise for IHC, RT-qPCR, ELISA and Western blot. In addition, another group of mice received daily epinephrine treatment for two weeks (0.05 mg/mL, 200 µL i.p.) (EPI, n = 8) to replicate the effects of exercise on tumors in vivo. Lewis lung cancer cells were treated with different concentrations of epinephrine (0, 5, 10, 20 µM) to detect the effect of epinephrine on chemokine levels via ELISA and RT-qPCR.ResultsThis study reveals that both pre- and post-cancer exercise effectively impede the tumor progression. Exercise led to an increase in EPI levels and the infiltration of CD8+ T cell into the lung tumor. Exercise-induced elevation of EPI is involved in the regulation of Ccl5 and Cxcl10 levels further leading to enhanced CD8+ T cell infiltration and ultimately inhibiting tumor progression.ConclusionExercise training enhance the anti-tumor immunity of lung cancer individuals. These findings will provide valuable insights for the future application of exercise therapy in clinical practice.

Does the presence and amount of epinephrine in 2% lidocaine affect its anesthetic efficacy in the management of symptomatic maxillary molars with irreversible pulpitis?

BackgroundThis was a randomized controlled clinical trial that aimed to evaluate the anesthetic efficacy of 2% lidocaine combined with different concentrations of epinephrine (plain, 1:200,000 and 1:80,000) during endodontic treatment of maxillary molars with symptomatic irreversible pulpitis.MethodsThe trial included 144 adult patients who were randomly allocated to three treatment groups. All patients received buccal-plus-palatal infiltration. After 10 min, pulp sensibility testing was performed using an electric pulp test (EPT). If a tooth responded positively, anesthesia was considered to have failed. In the case of a negative EPT response, endodontic access was initiated under rubber dam isolation. The success of anesthesia was defined as having a pain score less than 55 on the Heft Parker visual analog scale (HP VAS), which was categorized as ‘no pain’ or ‘faint/weak/mild’ pain on the HP VAS. Baseline pre-injection and post-injection maximum heart rates were recorded. The Pearson chi-square test was used to analyze the anesthetic success rates at 5% significance.ResultsPlain 2% lidocaine and 2% lidocaine with 1:200,000 epinephrine and 1:80,000 epinephrine had anesthetic success rates of 18.75%, 72.9%, and 82.3%, respectively. Statistical analysis indicated significant differences between the groups (P < 0.001, χ2 = 47.5, df = 2). The maximum heart rate increase was seen with 2% lidocaine solution with epinephrine.ConclusionAdding epinephrine to 2% lidocaine significantly improves its anesthetic success rates during the root canal treatment of maxillary molars with symptomatic irreversible pulpitis.

Bone Regeneration in Rat using Polycaprolactone/Gelatin/Epinephrine Scaffold

Solid supports like the extracellular matrix network are necessary for bone cell attachment and start healing in the damaged bone. Scaffolds which are made of different materials are widely used as a supportive structure in bone tissue engineering. In the current study, a 3-D Polycaprolactone/Gelatin bone scaffold was developed by blending electrospinning and freeze-drying techniques for bone tissue engineering. To improve the efficiency of the scaffold, different concentrations of epinephrine due to its effect on bone healing were loaded. Fabricated scaffolds were characterized by different tests such as surface morphology, FTIR, porosity, compressive strength, water contact angle, degradation rate. The interaction between prepared scaffolds and blood and cells was evaluated by hemolysis, and MTT test, respectively, and bone healing was evaluated by a rat calvaria defect model. Based on the results, the porosity of scaffolds was about 75% and by adding epinephrine, mechanical strength decreased while due to the hydrophilic properties of it, degradation rate increased. In vivo and in vitro studies showed the best cell proliferation and bone healing were in PCL/Gelatin/Epinephrine1%-treated group. These results showed the positive effect of fabricated scaffold on osteogenesis and bone healing and the possibility of using it in clinical trials.

Anaesthetic efficacy of 2% lidocaine with different concentrations of epinephrine (1:80,000 and 1:200,000) in intraligamentary injection after a failed primary inferior alveolar nerve block: a randomized double-blind study

Introduction: The present study evaluated the anaesthetic efficacy of 2% lidocaine with 1:80,000 epinephrine vs. 2% lidocaine with 1:200,000 given as supplemental intraligamentary injections after a failed inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis. The effect of these solutions on the heart rate was also evaluated.Methods: One-hundred-eighteen adult patients with symptomatic irreversible pulpits in a mandibular first or second molar, received an initial IANB with 2% lidocaine with 1:80,000 epinephrine. Pain during the endodontic treatment was assessed using a visual analogue scale (Heft-Parker VAS). Eighty-eight patients with unsuccessful anaesthesia were randomly allocated to one of the two treatment groups: one group received 0.6 mL/root of supplementary intraligamentary injection of 2% lidocaine with 1:80,000 epinephrine; while the second group received 2% lidocaine with 1:200,000 epinephrine. Endodontic treatment was re-initiated. Success after primary injection or supplementary injection was defined as no or mild pain (pain score ≤54 mm on HP VAS) during access preparation and root canal instrumentation. Heart rate was monitored using a finger pulse oximeter. The anaesthetic success rates were analyzed with the Pearson chi-square test at 5% significance levels. The heart rate changes were analyzed using the t-test.Results: The anaesthetic success rate in patients receiving supplementary intraligamentary injections in 1:80,000 epinephrine group was 82%, while the intraligamentary injections with 2% lidocaine with 1:200,000 epinephrine were successful in 57% of cases. The difference was statistically significant (χ2=6.4, p = .011). There was no significant effect of both the anaesthetic agents on the mean heart rate.Conclusions: Both 2% lidocaine with 1:80,000 epinephrine and 2% lidocaine with 1:200,000 epinephrine improved the success rates after a failed primary anaesthetic injection. The 1:80,000 epinephrine group was significantly more successful.

Stimulation role of epinephrine in transcription of the melatonin synthesis key enzyme AANAT in the pineal gland of broilers.

Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine control of the synthesis of melatonin is well documented; however, few reports have described the effects of epinephrine on the synthesis of melatonin. In this study, the effect of epinephrine on melatonin synthesis was investigated by adding different concentrations of epinephrine or norepinephrine to broiler pineal glands cultured in vitro. In addition, we investigated how epinephrine regulates the synthesis of melatonin and the transcription of the key melatonin synthesis enzyme AANAT. We determined the abundance of melatonin, norepinephrine, and epinephrine in broiler serum and the mRNA expression levels of key enzymes under different light conditions. The minimum concentrations of epinephrine and norepinephrine required to recover the melatonin synthesis rhythm in pineal cells were 10-13 and 10-11mol/L, respectively. Under various light durations, epinephrine reached maximum levels two hours earlier than melatonin. These results demonstrate for the first time that epinephrine can increase the synthesis of melatonin by increasing the transcription of AANAT.

Inducers and autoinducers on Salmonella enterica serovar Typhimurium motility, growth and gene expression

Genus Salmonella bacteria are among the major pathogenic microorganisms in food. This bacterium pathogenicity is related to a number of virulence factors, among which its flagella. Flagellum expression is one of the virulence factors modulated by Quorum Sensing. Epinephrine produced by mammals uses the same signaling pathway of the 3 bacteria autoinducer. This study evaluated the effect of molecules inducer (epinephrine) and autoinducers (autoinducer 2 and autoinducer 3) and their association with the motility, growth and expression genes flhC, fliA, fliY, motA, motB e fliC of Salmonella Typhimurium (ST). Initially, ST was inoculated in BHI. Then, motility assays, growth curves and gene expression were performed by testing different concentrations of epinephrine (50, 125, 250, 500µM), conditioned medium (10 and 50%) and a combination of these. ST was exposed to different concentrations of epinephrine, conditioned medium and an association of both. Following, motility assays, bacterial growth and gene expression were performed. The results obtained showed that the combination of 500uM epinephrine with 50% conditioned medium increased ST bacterial motility by increasing the expression of genes involved in flagellum assembly.

Hemodynamic changes following injection of local anesthetics with different concentrations of epinephrine during simple tooth extraction: A prospective randomized clinical trial

Background Presence of epinephrine in local anesthetic cartridge increases the duration of local anesthesia (LA), decreases the risk of toxicity, and provides hemostasis. However, the unfavorable effects are increasing heart rate (HR) and raising blood pressure (BP). The aim was to evaluate hemodynamic changes in the BP, HR, and oxygen saturation (SpO2) of normal patients undergoing tooth extraction using LA with various epinephrine concentrations. Material and Methods A prospective randomized clinical trial was conducted on 120 patients who were divided randomly into 3 parallel groups according to the LA received. Group 1: lidocaine 2% with epinephrine 1:80,000 (L80). Group 2: articaine 4% with epinephrine 1:100,000 (A100). Group 3: articaine 4% with epinephrine 1:200,000 (A200). Inclusion criteria: normal patients whose BP < 140/90. Exclusion criteria: hypertension, cardiovascular disease, hyperthyroidism, pregnancy, and allergy to LA. BP, HR, and (SpO2) were evaluated in 3 different time points: 3 minutes before LA, 3 minutes after LA, and 3 minutes after extraction. Results Systolic blood pressure (SBP) significantly increased after injection of L80 and continued after extraction to be significant than pre-injection. SBP significantly increased after injection of A100 then decreased after extraction. In the group of A200, SBP insignificantly decreased after injection then increased after extraction. The increasing of SBP between time point 1and 2 was significantly higher in G1 than G3 (p=0.014). Diastolic blood pressure decreased after LA in the 3 groups; however it was significant only with L80, then increased after extraction for all. Conclusions The changings of DBP, HR and SpO2 after anesthesia and extraction showed no significant difference among the three groups. However, A200 had significant lesser effect on SBP than L80 and the least effect on other parameters. Therefore, A200 is considered safer than L80 and A100 and is recommended for LA before teeth extraction in normal patient. Key words:Local anesthesia, lidocaine, epinephrine 1:80,000, articaine, epinephrine 1:100,000, epinephrine 1:200,000, tooth extraction.

Changes in the Blood Flow of the Optic Nerve Head Induced by Different Concentrations of Epinephrine in Intravitreal Infusion During Vitreous Surgery

We investigated whether intravitreal infusion solution containing epinephrine affects optic nerve head (ONH) blood flow during vitreous surgeries. The subjects were 22 patients with epimacular membrane or idiopathic macular hole. During vitreous surgery, ONH blood flow was examined before and 10 minutes after intravitreal infusion of solution containing epinephrine, via a laser speckle flowgraphy (LSFG) technique modified for acquiring measurements in a supine position. Epinephrine concentration was set at 1.0 mg/500 mL (1:500,000) or 0.5 mg/500 mL (1:1,000,000), with each concentration assigned to 11 consecutive patients. Relative pupil diameter, IOP, blood pressure, and pulse rate also were measured. A significant reduction in blood flow throughout the ONH was induced by intravitreal infusion of epinephrine at 1:500,000, but not at 1:1,000,000. Blood flow in ONH tissue was diminished at both concentrations, while that in vessels of the ONH was not altered significantly by either concentration. Both epinephrine concentrations induced significant pupillary dilatation, but no significant changes in IOP, blood pressure, or pulse rate. This study suggests that epinephrine, used in combination with intravitreal infusion solution, may decrease ONH blood flow during vitreous surgeries, as indicated by measurements obtained via a modified LSFG technique. Attention must be paid to the effects of intravitreal infusion of epinephrine on ocular circulation, particularly ONH blood flow.

Comparison of the anaesthetic efficacy of epinephrine concentrations (1 : 80 000 and 1 : 200 000) in 2% lidocaine for inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: a randomized, double‐blind clinical trial

The aim of this randomized controlled, double-blind trial was to comparatively evaluate the anaesthetic efficacy and injection pain of 1.8 mL of 2% lidocaine with different concentrations of epinephrine (1 : 80 000 and 1 : 200 000) in patients with symptomatic irreversible pulpitis. Sixty-two adult volunteers, actively experiencing pain, were randomly allocated into 2 groups and received 1.8 mL of 2% lidocaine with either 1 : 80 000 or 1 : 200 000 epinephrine concentration. Endodontic access preparation was initiated 15 min after the initial IANB. Pain during treatment was recorded using the Heft-Parker visual analogue scale (HP VAS). The primary outcome measure, and the definition of 'success', was the ability to undertake pulp access and canal instrumentation with no or mild pain (HP VAS score <55 mm). Secondary outcome measure was the pain experienced during LA solution deposition. Statistical analysis was performed using Mann-Whitney U-test and chi-square test. The anaesthetic success rates of 2% lidocaine solutions containing 1 : 80 000 and 1 : 200 000 epinephrine concentrations were 20% and 28%, respectively. The difference was not statistically significant. There was also no significant difference in the pain experienced during deposition of the solutions. Two percent lidocaine solution used for IANB achieved similar success rates when used with 1 : 80 000 or 1 : 200 000 epinephrine concentration.

The Effects of Different Concentrations of Epinephrine Adjuvant to Levobupivacaine on Wound Healing

Objective: Local anesthetics (LAs) and epinephrine are often combined for infiltration of surgical sites for their wide-range effects. The aim of our study is to investigate the effects of different concentrations of epinephrine added to levobupivacaine on wound healing. Methods: Forty female albino Wistar rats were divided into four groups. 3 ml of 3,75mg/ml levobupivacaine was applicated for all groups. In the control group (C) (n=10), 1ml isotonic saline was added, and in group A10 (10 µg/ml) (n=10), 1ml 1/100,000 adrenaline; in group A5 (5 µg/ml) (n=10), 1ml 1/200,000 adrenaline; and in group A2,5 (2,5 µg/ml) (n=10), 1ml 1/400,000 adrenaline. Two minutes after the infiltration of the drug combination into subcutaneous tissue, 3cm longitudinal cutaneous-subcutaneous incisions were performed on the mid-dorsal line under sterile conditions. Incisions were sutured with 4/0 sharp prolen with six sutures. Postoperative 8th-day rats were sacrificed to evaluate wound healing. Tissue burst pressures (TBP) and tissue hydroxyproline levels (THP) were measured, and histopathological evaluation for a fibrotic index was performed. A One-Way ANOVA and Chi-square test were used for statistical analyses. Results: There was no statistically significant difference between groups according to TBP and THP levels (p=0.4, p=0.201 respectively). Fibrotic index values were significantly higher in epinephrine groups (p=0,001), and were highest in A2,5. Conclusions: Epinephrine added to levobupivacaine in low concentrations accelerates wound healing in the early phase by stimulating fibrosis, and has no adverse effects on surgical sites. Long-term studies are needed for late effects of epinephrine adjuvant levobupivacaine.

Clinical study of hemodynamic changes comparing 4% articaine hydrochloride with 1:100,000 and 1:200,000 epinephrine

To evaluate hemodynamic changes with the use of 4% articaine and 2 different concentrations of epinephrine (1:100,000 and 1:200,000) in the surgical removal of symmetrically positioned lower third molars. A prospective, randomized, double-blind clinical trial was carried out involving 42 patients each undergoing 2 surgeries on separate occasions under local anesthesia with 4% articaine and either epinephrine 1:100,000 or 1:200,000. The following parameters were assessed at 4 different moments: systolic, diastolic, and mean blood pressure; heart rate; oxygen saturation; rate pressure product (RPP); and pressure rate quotient (PRQ). The concentration of epinephrine did not affect diastolic blood pressure or oxygen saturation during the surgeries. Significant differences between were detected for heart rate, RPP, and PRQ (P < .05). The epinephrine concentration (1:100,000 or 1:200,000) in a 4% articaine solution influences hemodynamic parameters without perceptible clinical changes in healthy patients undergoing lower third molar removal.

Epinephrine's effect in varying concentrations on the end artery organ in an animal model.

To determine the concentration of epinephrine that causes end artery necrosis and ischemia. An experimental study. Animal Laboratory of Khordad Hospital, Tehran, Iran, from September 2007 to June 2008. This study was done on 54 ear flaps from 9 rabbits [9 (rabbits) x2 (ears) x3 (splits) =54] divided into three groups of 18 ear flaps each. Nine of the ear flaps were randomized as control and nine of them were randomized as study group. The different concentrations of epinephrine and lidocaine 1% were injected in study groups but only 1% lidocaine was injected in control groups. Study group 1 received 1/200000, group 2 received 1/100000 and group 3 received 1/500000 concentration of epinephrine respectively. There was no evidence of necrosis in the control and study groups 1 and 2. However, 4 out of 9 of the ear flaps showed clear evidence of tissue necrosis in group 3. Injecting epinephrine in 1/200000 and 1/100000 concentrations had no side effect for the end artery of the rabbit ear flaps, but 1/50000 concentration is shown that it can cause tissue necrosis. Further studies need to be done in order to find out the effects of epinephrine with the same concentrations on the human end artery.

The Hemostatic and Hemodynamic Effects of Epinephrine During Endoscopic Sinus Surgery

To assess the hemodynamic and hemostatic effects of 2 different concentrations of epinephrine in local anesthetic used during functional endoscopic sinus surgery (FESS). Injection of local anesthetic containing epinephrine during endoscopic sinus surgery, while providing hemostasis, has been associated with cardiac adverse effects such as tachycardia, hypertension, as well as arrhythmias. Double-blind, randomized clinical trial. Tertiary referral center. A total of 140 patients undergoing FESS randomly divided into 2 groups, with group 1 receiving lidocaine hydrochloride, 2%, with 1:100 000 epinephrine and group 2, lidocaine, 2%, with 1:200 000 epinephrine. Baseline and postinjection hemodynamic parameters were recorded at 1-minute intervals for 5 minutes. Patient demographics, the extent of surgery, and the presence of polyps were recorded in both groups. Hemodynamic and hemostatic parameters and intraoperative blood loss were compared. Significant hemodynamic fluctuations were noted following injection of lidocaine, 2%, with 1:100 000 epinephrine (group 1). Increases in heart rate and systolic, diastolic, and mean arterial blood pressure were noted in group 1 patients. The increase was found to be significant (P < .001) in the first and second minutes after injection and decreased to baseline level by the fifth minute. This fluctuation was not noted in group 2 patients, who received lidocaine, 2%, with 1:200 000 epinephrine. Using a standardized scale to assess surgical bleeding, no statistical difference in the 2 groups was observed (P > .05). Submucosal injection of lidocaine, 2%, with 1:200 000 epinephrine during FESS does not lead to hemodynamic fluctuations or increased intraoperative bleeding compared with lidocaine, 2%, with 1:100 000 epinephrine. clinicaltrials.gov Identifier: NCT00852410.

The effects of epinephrine in local anesthetics on plasma catecholamine and hemodynamic responses

In order to clarify the influence of epinephrine in local anesthetics on endogenous epinephrine, we examined the concentration of plasma catecholamines (epinephrine and norepinephrine) and hemodynamics by administering 4 ml of 2% lidocaine containing different concentrations of epinephrine. Forty-three healthy adult male volunteers were divided into five groups according to epinephrine concentration: 0-microg (group I), 10-microg (group II), 20-microg (group III), 40-microg (group IV), and 50-microg (group V). The parameters were examined immediately, and at 1, 2, 3, 4, 5, 10, 15, and 20 min after the injection. In groups II, III, IV, and V, the plasma epinephrine concentration was elevated to peak at 5 min after the injection, after which it started to decline. The amount of increase in the plasma epinephrine concentration at 5 min showed a highly positive correlation with the amount of epinephrine added to the local anesthetic in groups II, III, and IV. In group V the plasma epinephrine concentration showed a marked increase as compared to the baseline level. Plasma norepinephrine concentrations were found to be significantly elevated at 15 and 20 min in group V. A decrease in systolic blood pressure was observed at 4 and 5 min in group II. A decrease in diastolic blood pressure was observed at 5 min in group II; at 3, 4, and 5 min in group IV; and at 2, 3, 4, and 5 min in group V. Heart rate revealed no significant differences from baseline level in any of the groups and there were no significant differences among the groups. It is suggested that exogenous epinephrine added to a local anesthetic may stimulate the presynaptic beta2 receptors on sympathetic nerve endings and on the adrenomedulla, and accelerate the release of endogenous epinephrine.

Effect of age and endurance training on the capacity for epinephrine-stimulated gluconeogenesis in rat hepatocytes.

The effects of endurance training on hepatic glucose production (HGP) from lactate were examined in 24-h-fasted young (4 mo) and old (24 mo) male Fischer 344 rats by using the isolated-hepatocyte technique. The liver cells were incubated for 30 min with 5 mM lactate ([U-14C]lactate; 25000 dpm/ml) and nine different concentrations of epinephrine (Epi). Basal HGP (with lactate only and no Epi) was significantly greater for young trained (T) (99.6 +/- 6.2 nmol/mg protein) compared with young controls (C) (78.2 +/- 6.0 nmol/mg protein). The basal HGP was also significantly greater for old T (97.3 +/- 5.9 nmol/mg protein) compared with old C (72.2 +/- 3.9 nmol/mg protein). After the incubation with the various concentrations of Epi, Hanes-Woolf plots were generated to determine kinetic constants (Vmax and EC50). Maximal Epi-stimulated hepatic glucose production (Vmax) was significantly greater for young T (142.5 +/- 6.5 nmol/mg protein) compared with young C (110.9 +/- 4.8 nmol/mg protein). Similarly, the Vmax was significantly greater for old T (138.2 +/- 5.0 nmol/mg protein) compared with old C (103.9 +/- 2.5 nmol/mg protein). Finally, there was an increase in the EC50 from the hepatocytes of old T (56.2 +/- 6.2 nM) compared with young T (32.6 +/- 4.9 nM). In like manner, there was an increase in the EC50 from the hepatocytes of old C (59.7 +/- 5.8 nM) compared with young C (33.1 +/- 2.7 nM). The results suggest that training elevates HGP in the basal and maximally Epi-stimulated condition, but with age there is a decline in EC50 that is independent of training status.

The promoting effect of epinephrine on lipopolysaccharide-induced interleukin-8 production in whole blood may be mediated by thromboxane A2

Epinephrine is known to enhance lipopolysaccharide (LPS)-induced interleukin (IL)-8 secretion in a platelet dependent manner. To determine whether thromboxane A2 (TxA2; a product from activated platelets) is involved in this process, blood samples drawn either before or 2 h after oral administration of 440 mg acetylsalicylic acid (ASA) were stimulated with LPS (5 ng mL(-1)) and different concentrations of epinephrine were added (0.1-100.0 micromol L(-1)). ASA ingestion significantly (global P < 0.05) reduced the enhancing effect of epinephrine on LPS-induced IL-8 release by 15-28%. To further explore whether TxA2 may be involved in this process, a TxA2 agonist (U46619) was added to whole blood together with LPS instead of epinephrine. U46619 mimicked the epinephrine effect: 20 ng mL(-1) U46619 enhanced LPS-induced IL-8 release by 39% (P < 0.05). Furthermore, preincubation of whole blood with 75 micro mol L-1 or 150 micromol L(-1) SQ29548, a TxA2 receptor antagonist, completely blocked epinephrine's promoting effect on LPS-induced IL-8 release. Since thrombin-activated platelets have been reported to be important in the production of IL-8 in monocytes through the activation of monocytes by exposed RANTES in a P-selectin-dependent reaction, we suggest that the epinephrine effect is mediated by enhanced TxA2 production and subsequent rise in the exposure of RANTES and P-selectin on the platelets of whole blood.

Anti-Arrhythmic Effect of Wild Honey Against Catecholamines Cardiotoxicity

The present study is a trial to suppress or attenuate the cardiotoxicity of catecholamines, which have been developed synthetically for the treatment of several cardiovascular disorders and conditions such as asthma and nasal congestion. Epinephrine (Adrenaline) is the most commonly available inotrope and in many cases the most appropriate drug to maintain blood pressure. However, tachycardia, ventricular arrhythmias and hypertension are side effects of this drug. In this investigation, induction of catecholamines cardiotoxicity was experimentally achieved using epinephrine. In isolated toads’hearts, the cardiac arrhythmias produced by different concentrations of epinephrine (10, 50, 100, 200 and 300 ng mlG ) 1

An evaluation of 2% lidocaine with different concentrations of epinephrine for inferior alveolar nerve block

The purpose of this study was to compare the degree of anesthesia obtained with 2% lidocaine with three different concentrations of epinephrine for inferior alveolar nerve block. Using a repeated measures design, 30 subjects randomly received an inferior alveolar injection using masked cartridges of each solution at three successive appointments. The first molar, first premolar, lateral incisor, and contralateral canine (control) were blindly tested with an Analytic Technology pulp tester at 3-min cycles for 50 min. No statistically significant differences in success and failure were found among the 1:50,000, 1:80,000, and 1:100,000 concentrations of epinephrine.

Myocardial adrenergic changes at two stages of heart failure due to adriamycin treatment in rats

Changes in myocardial norepinephrine (NE) levels, turnover, uptake, and release in rats were examined at two stages of cardiac dysfunction induced by adriamycin (ADR) given intraperitoneally in six equal doses over a period of 2 wk for a cumulative dose of 15 mg/kg. At 3 wk posttreatment, ADR-treated animals showed no changes in left ventricular systolic pressure (LVSP), aortic systolic pressure (ASP), and aortic diastolic pressure (ADP) but left ventricular end-diastolic pressure (LVEDP) was significantly higher. At 6 wk posttreatment, LVSP, ASP, and ADP were significantly lower and LVEDP remained elevated. Animals in both ADR-treated groups showed signs of congestive heart failure as indicated by ascites, congestive liver, and elevated LVEDP. Structural changes typical of ADR cardiomyopathy were more pronounced in the 6-wk group. In vivo hemodynamic as well as in vitro muscle function response to different concentrations of epinephrine was depressed in its duration as well as extent in both 3- and 6-wk ADR-treated groups. Myocardial NE levels were increased in the 3-wk group but were depressed in the 6-wk group. NE turnover was faster in both 3- and 6-wk ADR groups, uptake was increased only in the 6-wk group, and release was unchanged. These data show increased cardiac sympathetic tone at both stages of ADR-induced congestive heart failure.

Blockade of hyperkalemia and hyperglycemia induced by epinephrine in frog liver and in cats.

Dihydroergotamine (DHE) and Dibenamine are both known to block the hyperkalemic response to intravenously injected epinephrine. By simultaneously sampling blood from the hepatic vein and from the carotid artery it was possible to demonstrate that these blocking agents act directly on the liver. DHE is also known to decrease the hyperglycemic response to epinephrine, an observation confirmed in the present work. Although Dibenamine is said by some to be ineffective in this respect, we found that it significantly decreased the hyperglycemia. Various dosage combinations of DHE were ineffective in changing the potassium or glucose losses induced by different concentrations of epinephrine administered to the isolated perfused frog liver. Dibenamine also exhibited no effect on the response of the frog liver.