CK Concentrations Research Articles

Caffeine Does Not Augment Markers of Muscle Damage or Leukocytosis Following Resistance Exercise

The purpose of this study was to evaluate the effects of caffeine ingestion before a resistance exercise session on markers of muscle damage (CK, LDH, ALT, AST) and leukocyte levels. Fifteen soccer athletes completed two resistance exercise sessions that differed only in the ingestion of caffeine or a placebo preworkout. CK concentration increased significantly following the caffeine session (415.8+/-62.8 to 542.0+/-73.5) and the placebo session (411.5+/-43.3 to 545.8+/-59.9), with no significant differences between sessions. Similarly, LDH concentration increased significantly following the caffeine session (377.5+/-18.0 to 580.5+/-36.1) and the placebo session (384.8+/-13.9 to 570.4+/-36.1), with no significant differences between sessions. Both sessions resulted in significant increases in the total leukocyte count (caffeine=6.24+/-2.08 to 8.84+/-3.41; placebo=6.36+/-2.34 to 8.77+/-3.20), neutrophils (caffeine=3.37+/-0.13 to 5.15+/-0.28; placebo=3.46+/-0.17 to 5.12+/-0.24), lymphocytes (caffeine=2.19+/-0.091 to 2.78+/-0.10; placebo=2.17+/-0.100 to 2.75+/-0.11), and monocytes (caffeine=0.53+/-0.02 to 0.72+/-0.06; placebo=0.56+/-0.03 to 0.69+/-0.04), with no significant differences between sessions. Ingestion of caffeine at 4.5 mg/kg(-1) did not augment markers of muscle damage or leukocyte levels above that which occurs through resistance exercise alone.

The Effect of Oral Vs. Intravenous Rehydration on Circulating Myoglobin and Creatine Kinase

Physical activity of significant intensity and duration may cause varying degrees of skeletal muscle damage, but it is unclear whether mode of rehydration will attenuate muscle tissue disruption caused by exercise in the heat. To examine the effects of the mode of rehydration on markers of muscle damage (myoglobin and creatine kinase [CK]), 11 healthy active men (age = 23 +/- 4 years, body mass = 80.9 +/- 3.9 kg, height = 180.5 +/- 5.4 cm) completed 4 experimental trials consisting of an exercise dehydration protocol (to -4% of baseline body mass), followed by a rehydration period (oral, intravenous [IV], oral and IV combined, and ad libitum), and finishing with an intense exercise challenge that included treadmill running and sprinting and a box lifting protocol. During rehydration, subjects returned to -2% of baseline body mass unless completing the ad libitum trial during which they consumed fluids as thirst dictated. Myoglobin (Mb) and CK were measured during euhydrated rest. Post-exercise blood was drawn at 1 and 24 hours post exercise challenge for Mb and CK, respectively. Urine was collected during euhydrated rest and 1-hour post exercise challenge for measurement of Mb clearance. Mb concentrations increased significantly from pre (1.06 +/- 0.20, 0.88 +/- 0.07, 1.15 +/- 0.25 and 0.92 +/- 0.06 nmol.L) to post (1.52 +/- 0.28, 1.44 +/- 0.11, 1.71 +/- 0.45 and 1.58 +/- 0.39) for IV, oral, oral and IV combined, and ad libitum, respectively, but were not significantly different among trials. Serum CK concentrations remained within the normal physiological range for all trials. Thus, despite previous research that clearly indicates the benefit of ingesting fluids during exercise to attenuate muscle damage, there were no significant differences between the modes of rehydration on circulating Mb and CK.

Effects of whole-body cryotherapy on serum mediators of inflammation and serum muscle enzymes in athletes

Whole-body cryotherapy (WBC) covers a wide range of therapeutic applications and consists of briefly exposing the body to extremely cold air. In sports medicine, WBC is used to improve recovery from muscle injury; however, empirical studies on its application to this area are lacking. To fill this gap, we compared changes in immunological parameters (C3, IgA, IgM, IgG, C-reactive protein, PGE2), cytokines (IL-2, IL-8, IL-10), adhesion molecules (sICAM-1), and muscle enzymes (creatine kinase [CK], lactate dehydrogenase [LAD]) before and after WBC in 10 top-level Italian National team rugby players. The subjects underwent five sessions on alternate days once daily for 1 week. During the study period, the training workload was the same as that of the previous weeks. Compared to baseline values, immunological parameters remained unchanged, while CK and LAD levels significantly decreased after treatment. No alterations in immunological function were observed but there is a decrease in pro-inflammatory cytokine/chemokine and an increase in anti-inflammatory cytokine. As measured by changes in serum CK and LAD concentrations, and cytokines pathway, short-term cold air exposure was found to improve recovery from exercise-induced muscle injury and/or damage associated with intense physical training.

Successful Switch to Olanzapine after Rhabdomyolysis Caused by Water Intoxication and Clozapine Use

We report on a case of rhabdomyolysis induced by the correction of hyponatremia after psychogenic polydipsia and clozapine use, where the switch to a high dose of olanzapine resulted in the non-recurrence of rhabdomyolysis. The 46-year-old patient with the diagnosis of schizophrenia paranoid type, who had been on clozapine treatment for the previous 4 years, was admitted with the symptoms of generalized seizure and vomiting, and as severe hyponatremia was proved, its correction with the parallel use of clozapine treatment was done. CK concentrations increased to 48 120 U/L without any symptom of neuroleptic malignant syndrome. To prevent acute renal insufficiency, high-volume alkaline diuresis was initiated and clozapine was tapered and stopped. On the day 12 of treatment, olanzapine was started and was elevated to 30 mg/day. CK concentration began to fall returning to the normal concentration on day 20. Six months after the switch to olanzapine no recurrence of rhabdomyolysis was detected; clinical and laboratory findings were normal. We suggest that after a benzodiazepine-type antipychotic-induced rhabdomyolysis, a switch to another atypical antipsychotic can be a cautious clinical strategy.

Xylem-borne cytokinins: still in search of a role?

Leaf expansion and xylem cytokinin concentration ([X-CK]) decrease in response to nitrogen (N) deprivation. Debate continues over cause, effect, and correlation. Supporting studies provide, at best, correlative evidence that [X-CK] controls leaf growth in response to N-deprivation, while dissenting studies indicate that leaf growth responses to N can be independent of changes in X-CK supply to leaves. A model is proposed to evaluate the physiological significance to leaf growth of changes in plant and environment N concentrations, and plant CK concentrations.

Increase in serum troponin-I following rotational atherectomy reliably predicts the occurrence of reversible wall motion abnormalities

Background There is growing evidence that microdebris pulverized by rotational atherectomy (RA) may have a deleterious effect on coronary microcirculation and ventricular contraction. However, the incidence and the predictors of worsening of left ventricular wall motion following RA are unknown. Methods Thirty patients without a known previous anterior wall myocardial infarction who underwent RA-facilitated angioplasty for de novo lesions of left anterior descending coronary artery were evaluated. Global and anterior wall regional left ventricular ejection fraction (LVEF and AREF) were analyzed before and after RA. Serum troponin-I, CK, and CK-MB concentrations were assayed. Results Target lesion length was greater ( P = 0.03), post-procedural minimal lumen diameter was smaller ( P < 0.01), and serum troponin-I immediately after RA was higher ( P = 0.01) in 16 patients with a decrease in the AREF of at least 15% than in those without. Stepwise logistic regression analysis identified one independent predictor of such worsening of AREF, troponin-I≥0.1 ng/ml immediately after the procedure ( P < 0.01), with sensitivity of 81%, specificity of 79%, and relative risk of 3.8. Conclusions Our results suggest that RA can cause substantial deterioration in left ventricular wall motion. Serum troponin-I, a sensitive indicator of myocardial damage, may be useful in predicting reversible LV wall motion abnormalities following RA.

Effect of thermal conditioning during embryonic development on aspects of physiological responses of broilers to heat stress

The purpose of the present study was to investigate the effect of thermal conditioning, (through exposure to heat stress), during pre-hatch development on some physiological responses of post-hatch broilers to a post-natal heat stress challenge. Exposure to heat stress at this stage, we hope, may possibly induce epigenetic heat adaptation. Incubating eggs were exposed to temperature of 39.0°C for 2h from Day 13 to 17 of incubation. At 33, 35, 37, 39, 41 and 43d of age, the broilers hatched from these eggs were housed individually in open-circuit respiration cells. The climatic chambers were set to 22°C and increased to 30°C for 4h. O2 consumption and CO2 production of each chicken was monitored continuously in order to calculate the heat production. Blood samples were obtained before and during the 4h heat stress. Thermal conditioning during incubation did not affect the plasma T4, corticosterone, glucose, uric acid and CK concentrations. Temperature challenge, decreased plasma T3 of broilers of both groups but the decrease was greater in pre-conditioned broilers compared with controls. A similar trend was observed for triglycerides. These changes did not affect total heat production. Since decreased T3 and triglyceride levels are part of the mechanisms for thermoregulation, these suggest that thermal conditioning during incubation can improve the broiler chicken capability for thermotolerance at later post-hatch age.

Muscular fatigue, maximum strength an stress reactions of the shoulder musculature in paraplegics.

In paraplegic patients, shoulder complaints attributable to muscle dysbalances arising from the particular daily form of exercise are often observed. The goal of therapy is to correct these imbalances through muscular training, whereby eccentric exercise might offer advantages due to lower fatigue with concurrent higher maximum strength. This study therefore examines muscle fatigue, maximum strength, and suitability for paraplegics of eccentric exercise of the shoulder. Muscle fatigue, isokinetic peak torque, and EMG activity were determined eccentric (Ecc) and concentric (Con) in 41 paraplegic subjects (13 early rehabilitants; 16 trained in wheelchair sports; 12 untrained). Serum CK, myoglobin, and subjective pain were collected for one week after exercise. In eccentric exercise, there was less muscle fatigue in all groups. Highest Ecc/Con peak torque ratio was found in trained subjects in all movements, followed by the untrained and the early rehabilitants. EMG-activity was lower in eccentric compared to concentric exercise (Ecc/Con ratio <1). CK and myoglobin concentrations, like pain symptoms, showed a marked increase after exercise. It is concluded that the Ecc/Con strength patterns among paraplegics are altered. Eccentric exercise offers advantages on the basis of lower muscular fatigue independent of training status and lesion time and higher maximum strength with increasing duration of paraplegia and additional athletic training. However, due to structural damage and subjective pain eccentric exercise can only be recommended with reservations in therapy and training.

Acute coronary syndromes: unstable angina and non-Q-wave myocardial infarction.

Ischemic heart disease includes a wide spectrum of conditions, ranging from silent ischemia and exertion-induced angina, through unstable angina, to acute MI. Unstable angina occupies the center of this spectrum, causing disability and risk greater than that of chronic stable angina but less than that of acute MI1 (Fig 1⇓). Although non–Q-wave MI for many years was considered prognostically similar to unstable angina, recent longitudinal studies indicate that it is similar to Q-wave infarction2 3 (Fig 2⇓). Figure 1. Cumulative 6-month mortality from ischemic heart disease. Diagnosis on admission to hospital (n=21 761; 1985 to 1992). From Duke Cardiovascular Database. Reproduced with permission from Reference 1. Figure 2. Top, Cumulative 1-year combined death or MI among patients with Q-wave and non–Q-wave MI treated with fibrinolysis. Reproduced with permission from Reference 2. Bottom, Risk of subsequent cardiac events in stable convalescing patients after first non–Q-wave and Q-wave MI. Reproduced with permission from Reference 3. The concept of unstable angina has emerged from observations of frequent symptoms preceding acute MI, followed by prospective documentation that unstable symptoms frequently culminated in acute MI. The syndrome was rapidly accepted as a well-defined clinical entity as specific clinical manifestations, pathophysiological mechanisms, laboratory findings, and treatment became better characterized. Unstable angina is currently one of the leading causes of hospital admission for CAD, and non–Q-wave MI accounts for >30% of admissions for acute MI.1 4 Yet, the diagnosis of unstable angina remains clinical, based on symptom recognition. The physician caring for patients with unstable angina is in a privileged position of recognizing rapidly evolving CAD and being able to intervene to prevent irreversible left ventricular damage and progression of CAD. Unstable angina is classically described as a heterogeneous disease, referring to a wide spectrum of clinical manifestations from stable angina to MI, of disease …

PEAK TORQUE, EMG-ACTIVITY AND STRUCTURAL DAMAGE AFTER ECCENTRIC EXERCISE IN PARAPLEGIC WHEELCHAIR DRIVERS 126

Acute and chronic complaints are frequently observed due to increased shoulder stress in paraplegic wheelchair drivers. The cause of these complaints are often muscle dysbalances and muscle deficits in the stressed musculature. Muscular complaints attributable, among other factors, to structural damage are observed especially following eccentric exercise during therapy of these deficits. It is unclear whether differences in maximum strength and structural damage can be observed in dependence on the duration of the lesion and the training status. We examined a total of 41 paraplegic wheelchair drivers who were assigned to 3 groups (GI: untrained, lesion duration x=4.5 months; GII: trained, lesion duration x=175.1 months; GIII: untrained, lesion duration: x=209.5 months). Test parameters were peak torque(PT) and EMG-activity (EA) normalized to MVC after eccentric and concentric strength stress for all shoulder movements (extension EX, flexion FL, abduction AB, adduction AD, internal rotation IRO, external rotation ERO), and the serum CK and myoglobin (MYO) concentration over an observation period of 1 week. Differences in subjective pain were recorded in progressive observation using validated pain questionnaires (PDI, MPQ). Independent of group assignment, there was a decrease in PT in the sequence EX, FL/AD, AD/IRO, ERO. Higher PT and lower EA were measured in all groups in eccentric exercise for all shoulder movements (p<0.05). Increases in CK and MYO were considerably greater in GII (CK: 12327±8000U·1-1; MYO: 1954±1100μg·1-1) than in GI and GII (p<0.05). The PDI and MPQ records showed nearly identical patterns for all groups. It is concluded that, independent of the lesion duration, structural damage and muscular complaints must be anticipated during therapy of muscular deficits and dysbalances in the shoulder of paraplegic wheelchair drivers, especially following eccentric exercise. EA under eccentric stress is clearly lower than in concentric stress, in spite of greater PT. Since this is attributable to passive elasticity forces, a lower metabolic stress can be assumed. Eccentric exercise is thus very important in rehabilitation of shoulder complaints.

Heterophilic Antibodies Produce Spuriously Elevated Concentrations of the MB Isoenzyme of Creatine Kinase in a Selected Patient Population

Dual-site murine antibody-based immunoassays are commonly used in clinical laboratories to quantitate the MB isoenzyme of creatine kinase (CK-MB). Because the serum level of CK-MB is a relatively specific and sensitive indicator of myocardial ischemic damage, accurate quantitation is essential for a correct diagnosis. Heterophile antibodies (eg, human anti-murine antibodies) can interfere with these assays, however, and produce erroneous results. A subpopulation of 19 surgical patients with colorectal carcinoma who had received injections of an 125I-labeled murine monoclonal antibody directed against a tumor-associated glycoprotein was studied. Serum specimens from eight patients (42%) showed a marked increase in the level of CK-MB and normal total CK concentrations. The increased concentrations of CK-MB, which were attributed to interference by human antimurine antibodies, were substantially reduced in these specimens after a heterophile blocking reagent was added. However, this reagent did not significantly alter the serum level of CK-MB in patients who had clinical evidence of acute myocardial ischemia.

Increased creatine kinase brain isoenzyme concentration in cerebrospinal fluid with meningitis.

CPK-BB (CK-BB) isoenzyme is an intracellular enzyme released in various neurologic conditions, including central nervous system (CNS) infections. Activity of CK-BB in cerebrospinal fluid (CSF) was determined in 80 children by electrophoresis and densitometry. The possible correlation between CNS infection and CK concentrations was assessed. Significantly elevated concentrations of CK activity (P < 0.01) in the CSF were found in children with bacterial meningitis as compared with children with either aseptic meningitis or normal CSF findings. The data suggest the possibility of utilizing CSF CK activity to differentiate between bacterial and viral meningitis in situations where a routine CSF examination is inconclusive.

Cryoprostatectomy consistently elevates serum creatine kinase-MB isoenzyme

Study Objective: To measure serum CK-MB, a market of myocardial infarction (MI), in elderly men before and after cryoprostatectomy. Design: Serum CK-MB was measured on each patient before and after cryoprostatectomy. Each patient's preoperative result was used as control measurement for comparison with measurements made after cryoprostatectomy. Setting: Inpatient operating room and postanesthetic, recovery unit of a university-affiliated general hospital. Patients: 38 male patients, mean (SEM) age 69.1 ± 1.4 years, undergoing cryoprosta-tectomy. Interventions: All patients had a 12-lead ECG prior to surgery, in the recovery room, and 24 hours after surgery. Serum CK-MB was measured prior to induction of anesthesia, on arrival in the recovery room, and at 8 and 24 hours after surgery. Lactate dehydrogenase (LDH) and isoenzymes also were measured in 10 patients before and after cryoprostatectomy. Measurements and Main Results: All patients underwent uneventful cryoprostatectomy. No patients had new ECG changes after surgery. All patients had normal serum CK and CK-MB concentrations before surgery. Serum CK and CK-MB were significantly elevated after cryoprostatectomy ( p < 0.001). Enzyme values were greatest 8 hours after surgery: total CK mean 1453 ± 145 U/L (range 199 to 3,356 U/L); CK-MB mean 52 ±3 ng/ml (range 12 to 114 ng/ml) or 5.0 ± 0.5% of total CK (range 1.6% to 12.4%). All patients had significant elevations of LDH after cryoprostatectomy but did not show an increase in the ratio of LDH 1 to LDH 2 isoenzymes. Finally, unlike patients with an acute MI, the activity of CK-MB isoenzyme when measured by gel electrophoresis was two to three times greater (mean, 2.6 ± 0. 7) than the concentration measured with the monoclonal antibody assay in patients after cryoprostatectomy. Conclusion: Serum CK-MB is an unreliable test to diagnose a MI in patients who have undergone cryoprostatectomy.

Toxicity to Bovans Chicks ofCassia italicaSeeds

A toxicity study was made on Sudanese C. italica used in traditional medicine for the treatment of diverse ailments. C. italica seeds were fed to 7-day-old Bovans chicks at 10% and 2% of the diet for 6 weeks. Decreased body weight and efficiency of feed utilization and enterohepatonephrotoxicity were observed in chicks fed the 10% Cassia seed diet. These changes accompanied by anaemia were correlated with alteration in serum GGT, LDH and CK activities and concentrations of total cholesterol, copper, zinc, iron, total iron binding capacity and other serum constituents and hepatic trace elements. Organ lesions did not completely disappear 3 weeks after removal from the test diet. Two percent Cassia seed diet promoted the chicks' growth.

Acute illness myopathy

Two articles [1,2] in this issue discuss acute myopathy that can develop in the setting of critical illness. Patients usually develop acute myopathy when two of the following three conditions exist: 1) the patient is treated with a non-depolarizing neuromuscular blocking agent; 2) glucocorticoids are used; or 3) the patient has a febrile illness or sepsis. The articles indicate we do not know how to predict which patients will develop acute myopathy and that acute myopathy may resemble axonal neuropathy on EMG testing. Some patients with acute illness myopathy manifest myonecrosis with elevated serum CK concentration, while others do not have an appreciable increase in CK. It is likely that in …

Comparison between two post exercise cooling methods

SummaryForty‐two fit 3‐day‐event horses were tested under hot, humid ambient conditions to determine if application of cold water (mean 9°C) over the entire body surface after exercise would cool horses more quickly than regional application of tepid water (mean 31°C); and to determine if topical application of cold water caused myopathy. Horses were exercised under saddle for an average of 81 min. Heart rate data and post exercise plasma lactate concentrations characterised the work effort as low intensity work with short bouts of moderate intensity effort.Sixteen horses were studied in a crossover design on 2 consecutive days. Immediately after exercise, horses were randomly assigned to the hypercooling protocol (cold water on entire body surface) or the conventional protocol (tepid water on neck, shoulders, torso, underside and legs). Hypercooled horses (Group 1) had significantly lower rectal temperatures at 15, 20, 25 and 30 min after exercise compared to conventionally cooled horses (Group 2). In a supplemental study, an additional 19 horses (Group 3) were hypercooled after exercise. Mean rectal temperatures were significantly decreased from the immediate post exercise rectal temperature at 10, 15, 20 and 25 min after exercise. Based on physical examination and serum AST and CK concentrations, myopathy did not occur in any of the horses. These results suggest that application of cold water to the entire body surface relieves mild to moderate exertional hyperthermia quickly under hot, humid conditions; and that myopathy is not a common complication of this cooling approach.

Mechanism of inhibition of aldosterone secretion by a Ca2+ channel blocker in patients with essential hypertension and patients with primary aldosteronism

Three studies were conducted in order to investigate the suppressive effects of a calcium antagonist on aldosterone secretion and a possible mechanism. Study 1: A long-term (4 weeks) treatment with slow-release nifedipine (Nif), 40-60 mg/day, was performed in 9 in-patients with essential hypertension (EHT). Mean arterial pressure (MAP), plasma renin activity (PRA), plasma angiotensin II levels (pAII) and plasma aldosterone concentration (PAC) were determined before and after Nif treatment. Study 2: In another 7 in-patients with EHT, Nif treatment (40-60 mg, 7-10 days) was carried out to study its effect on aldosterone secretion in response to 2-hour ambulation, angiotensin II (AII) infusion (2.5 ng/kg/min, for 1-hour) and ACTH injection (2.5 mg i.v.). Study 3: The effects of Nif (40-60 mg/day, for 7-10 days) on MAP, PAC, serum potassium, potassium clearance (Ck) and changes in PAC or plasma cortisol levels in response to ACTH injection (2.5 mg i.v.) were studied in 6 in-patients with primary aldosteronism (PA). In patients with EHT, MAP was reduced significantly at 1 week and 4 weeks after the administration of Nif. PRA and pAII increased significantly, though the increase of PAC was not significant. In the low-renin EHT group, PAC was reduced significantly (Study 1). The increase of PAC in response to 2-hour ambulation or AII infusion was inhibited by Nif, but no inhibition of aldosterone response to ACTH was observed (Study 2). In patients with PA, Nif lowered MAP, PAC, and Ck, and elevated serum potassium concentration significantly. On the other hand, Nif had no effect on the aldosterone or cortisol response to ACTH (Study 3). These results indicated that the hypotensive effect of Nif is due in part to the inhibition of aldosterone secretion from the adrenal gland both in patients with EHT and in those with PA. Regarding the mechanism of the inhibition of aldosterone secretion by Nif, these data suggest that in patients with EHT, inhibition of the aldosterone response to AII is the most important factor, although it was not clear from this study whether Nif inhibits the potassium-induced aldosterone release or not. In patients with PA, ACTH-induced aldosterone secretion was not inhibited by Nif and the reduction of PAC is not likely via inhibition of AII action since the renin-angiotensin system is markedly suppressed. Reduced cytosolic calcium concentration in the adenomatous tissue by Nif may have something to do with the lowered aldosterone synthesis in PA.

EVALUATION OF LABORATORY TESTS AS A GUIDE TO DIAGNOSIS AND THERAPY OF MYOSITIS

Plasma CK concentrations have been widely used as the primary muscle enzyme marker for diagnosis and progression of myositis. Recently, total CK and CK-MB serum concentrations have been compared to, and used in conjunction with, serum concentrations of aspartate aminotransferase in diagnosis of myositis. The algorithmic use of CK, AST, and aldolase plasma concentrations to diagnose and categorize patients with myopathy may be a useful method of diagnosing specific muscle disease without invasive procedures. CAIII, as a specific marker for skeletal muscle damage, may replace CK as the enzyme of choice in diagnosis and progression of myositis and other muscle disease. Additional studies are required to determine the usefulness of carbonic anhydrase for the diagnosis and assessment of myositis.

Creatine kinase isoform electrophoresis for the early confirmation of myocardial infarction detected by timed sequential CK slope analysis.

Creatine kinase (CK)-MM and -MB isoforms were evaluated for the early diagnosis of myocardial infarction in patients aged over 65 years admitted to a district general hospital with acute chest pain. Samples were collected for standard cardiac enzymes, timed CK slope analysis, and CKMM and CKMB isoform analysis from 48 patients admitted with acute chest pain. CKMM and CKMB isoform analyses were conducted using a Helena Rep electrophoresis system under standard conditions supplied by the company. In addition to the results of the biochemical tests the discharge diagnosis of the patients were also recorded. CKMM isoform analysis resulted in three false-negative classifications of patients and one false-positive. The predictive value of this test was 100% for a positive result and 94% for a negative result. CKMB isoform analysis was less accurate and there were six false-negative results and five false-positive results. The predictive value of a positive result was 75% and 85% for a negative result. CK isoform analysis became unreliable when mean total CK levels in serum were 210 IU/l (+/- 171). CK isoform analysis may be of use in the investigation of patients whose samples have a total CK concentration greater than the reference range but was no better than timed CK slope analysis for the detection of myocardial infarction in patients aged more than 65 years.

Elevation of cytokines during open heart surgery with cardiopulmonary bypass: participation of interleukin 8 and 6 in reperfusion injury

Myocardial ischaemia is one of the major causes of low output syndrome during open heart surgery. Injury associated with ischaemia and reperfusion has been considered to result, in part, from the action of neutrophils, the interaction of neutrophils with vascular endothelial cells, and the effects of cytokines which are mediators that induce and modify reactions between these substances. We investigated cell injury in relation to the concentrations of interleukins 6 and 8 (IL-6 and IL-8), which have recently received attention as neutrophil activators. Neutrophil counts, granulocyte elastase (GEL), IL-6, IL-8, tumour necrosis factor-alpha (TNF-alpha), CK, and CK-MB concentrations were determined serially in 11 patients undergoing open heart surgery with cardiopulmonary bypass (CPB). Neutrophil counts (mean +/- SD 2717 +/- 2421 microliters-1 preoperatively) peaked 60 min after declamping the aorta at 7432 +/- 4357 microliters-1 (P < 0.01) and remained elevated 7136 +/- 5194 microliters-1 at 180 min (P < 0.01). Plasma GEL level (168 +/- 71 micrograms.L-1 preoperatively) peaked at 1134 +/- 453 micrograms.L-1 120 min after declamping of the aorta (P < 0.01) and remained elevated, 1062 +/- 467 micrograms.L-1, after 180 min (P < 0.01). Serum IL-6 level (118 +/- 59 pg.ml-1 preoperatively) peaked at 436 +/- 143 pg.ml-1 60 min after declamping of the aorta (P < 0.01) and remained elevated, 332 +/- 109 pg.ml-1, after 180 min. Serum IL-8 level (37 +/- 44 pg.ml-1 preoperatively) peaked at 169 +/- 86 pg.ml-1 at 60 min after declamping of the aorta (P < 0.001) and remained elevated at 113 +/- 78 pg.ml-1 180 min after declamping of the aorta.(ABSTRACT TRUNCATED AT 250 WORDS)