Assessment of leptin-to-adiponectin ratio in prediction of insulin resistance and nutrition status in a geriatric female population

Both obesity and malnutrition leading to cachexia and sarcopenia are relevant risk factors in the development of many diseases. They also increase mortality, also prolong hospitalisations and convalescence, and undoubtedly increase the cost of treatment, mostly in the elderly populations. The aim of the study was to assess the relationship between the levels of leptin and adiponectin with regard to insulin resistance and malnutrition status by studying a senior female population and to evaluate predictors of insulin resistance and malnutrition. A total of 88 elderly females were enrolled prospectively with a median age of 75 years. Anthropometric and biochemical parameters (fasting glucose, insulin, folic acid, vitamin B12 concentrations, lipid profile, complete blood count) were recorded along with a full geriatric assessment, have been made in all participants. A comprehensive nutritional phenotype has been established. Leptin and adiponectin concentrations were measured by applying immunoassay techniques. Lipid profile and other parameters were performed by biochemical methods. We observed significant decreases of albumin, alanine aminotransferase, insulin, and triglycerides concentrations with age. The risk of insulin resistance based on HOMA-IR index was decreased with age. Significantly higher concentrations of leptin, leptin-to-adiponectin ratio (LAR), hsCRP, fasting glucose, insulin in the insulin resistant subgroup in respect of normal sensitivity insulin cases were noted. The concentrations of albumin, aspartate aminotransferase, alanine aminotransferase and total cholesterol were significantly lower in those patients at risk of malnutrition than in the well-nourished subjects. LAR reached the most accurate AUC^ROC = 0.705 for insulin resistance prediction, with a cut-off value at 3.85. The greatest diagnostic power was presented by the albumin concentration with AUC^ROC = 0.761 and then LAR 0.718 in discriminating between well-nourished patients and those at risk of malnutrition. We suggest that the leptin-to-adiponectin ratio is suitable as a marker of insulin resistance and nutritional status in the elderly.

Role of glutathione metabolism and glutathione-related antioxidant defense systems in hypertension

The risk of developing chronic hypertension increases with age. Among others factors, increased oxidative stress is a well-recognized etiological factor for the development of hypertension. The co-occurrence of oxidative stress and hypertension may occur as a consequence of a decrease in antioxidant defense system activity or elevated reactive oxygen species generation. Glutathione is a major intracellular thiol-disulfide redox buffer that serves as a cofactor for many antioxidant enzymes. Glutathione-related parameters are altered in hypertension, suggesting that there is an association between the glutathione-related redox system and hypertension. In this review, we provide mechanistic explanations for how glutathione maintains blood pressure. More specifically, we discuss glutathione's role in combating oxidative stress and maintaining nitric oxide bioavailability via the formation of nitrosothiols and nitrosohemoglobin. Although impaired vasodilator responses are observed in S-nitrosothiol-deficient red blood cells, this potential hypertensive mechanism is currently overlooked in the literature. Here we fill in this gap by discussing the role of glutathione in nitric oxide metabolism and controlling blood pressure. We conclude that disturbances in glutathione metabolism might explain age-dependent increases in blood pressure.

Prohepcidin and iron metabolism parameters in the obese elderly patients with anemia

OBJECTIVE

To examine the impact of a body fat content on the concentration of a serum prohepcidin, iron metabolism parameters and inflammation markers in elderly patients with microcytic or normocytic anemia.

DESIGN

Clinical study with biochemical and anthropometric measurements.

SUBJECTS

Fifty two elderly patients (19 male, 33 female) with anemia, 65-91 years of age.

MEASUREMENTS

Prohepcidin, ferritin, soluble transferrin receptor, erythropoietin and interleukin-6 were measured using commercially available ELISA kits. Iron, TIBC, transferrin, C-reactive protein and complete blood count were assayed using standard laboratory methods. Body fat content, fat distribution and protein nutrition state parameters were assessed by means of anthropometry.

RESULTS

Mean serum prohepcidin levels were significantly higher in patients with high body fat content in comparison to patients with normal body fat content (224,85 vs 176,6 ng/ml). Prohepcidin levels of the elderly patients with anemia were positively correlated with biceps, subscapular and suprailiac skinfold thickness or body fat mass percentage. In our study serum prohepcidin levels do not correlate with any iron parameters or inflammation markers.

CONCLUSION

Summing up, the results of this study indicate that increased prohepcidin concentration, observed in obese elderly patients with anemia, may play an important role in iron deficiency development.

The analysis of dehydroepiandrosterone sulphate concentration in elderly age women depending on coexisting disease states

PURPOSE

The aim of the study was evaluation of dehydroepiandrosterone sulphate (DHEA-S) serum concentration in elderly women and determining interdependence between DHEA-S levels and occurrence of diseases typical for this period of life.

MATERIAL AND METHODS

The study was conducted on 103 elderly women (mean age 70.7 +/- 7.3 years). The control group consisted of 25 young and healthy women (mean age 33.5 +/- 1.7 years). The elderly patients were fully functional, well nourished, and only periodically required medical care due to chronic illnesses such as coronary heart disease, arterial hypertension, type 2 diabetes, osteoporosis, depression. DHEA-S serum concentration was determined by Spectria DHEA(S) RIA radioimmunological kit. Statistically significantly important decrease of DHEA-S serum concentration was determined in elderly women compared with the control group.

RESULTS

Mean blood serum DHEA-S concentration in elderly group was significantly lower compared to controls. Mean blood serum DHEA-S concentration was statistically significantly lower in the group of patients suffering from coronary heart disease, osteoporosis, and depression. Statistically significantly lower DHEA-S concentration was observed in patients with benign disorders of cognitive functions and depression compared with patients with correct MMSE and GDS results.

CONCLUSIONS

In elderly women DHEA-S concentration can turn out to be useful aging biomarker. Concentration of this hormone significantly decreases together with age, especially with coexisting diseases typical for this period of life.

Influence of the management of cervical carcinoma on the activity of catalase and glutathione peroxidase in erythrocytes

PURPOSE OF INVESTIGATION

The aim of the study was to determine the effect of different types of management on the activity of catalase (CAT) and glutathione peroxidase (GPx) in women with cervical carcinoma.

METHODS

The patients were divided into three groups according to the mode of treatment. Patients from the first group were treated brachytherapy prior to surgery. The second group received teletherapy before brachytherapy and additionally chemotherapy. The third group was treated with teletherapy after brachytherapy sessions.

RESULTS

CAT activity was higher while GPx activity was lower before and during therapy in all groups as compared to controls. Six months after the end of therapy, the activity of studied enzymes reached the values characteristic of healthy women. No significant differences in enzyme activity among the three groups were revealed.

CONCLUSION

Normalization of CAT and GPx activity may prove the efficacy of applied therapy in cervical cancer patients, however enzyme activity recovery was not dependent on treatment mode.

The analysis healthy behavior among elderly people in Juczyńiski's Inventory of Healthy Behavior

PURPOSE

The aim of our research was the analysis healthy behavior in people, who continued their education in the third age group at Universities and elderly hospitalized patients.

MATERIAL AND METHODS

The study group included students in the third age group at Universities and Senior Clubs and patients hospitalized in the Department and Clinic of Geriatrics, there were 87 women and 37 men, in total 124 people. The mean age of the evaluated people group was 67.6 years. The research was carried out by diagnostic poll method with the application of Juczyński's Inventory of Healthy Behavior (IoHB).

RESULTS

The studied people group showed a high level of health behavior, obtaining higher scores than standard for older people. This difference was statistically significant for all studied rates. In our study, the standardized rate was in general 6.50, including 6.39 for women and 6.76 for men. Such rate value of health behavior should be considered as average rather than high.

CONCLUSIONS

The older people in the present report have a high level of healthy behavior compared to the average for adult population.

[Evaluation of some selected structural and functional parameters of red blood cells as oxidative stress markers in elderly people]

The ageing process induces age-related involutionary changes and leads to increased occurrence of many diseases. One of the most important theories of ageing and development of many pathologies is the free radical theory, which assumes that ageing process leads to lost of oxidative balance.

THE AIM

of the research was to evaluate the degree of membrane lipid peroxidation, internal microviscosity, activity of membrane ATPase, both total and Na(+)K(+)-dependent, and markers of oxidative damage in erythrocyte membrane protein in elderly people.

MATERIAL

The examination was performed on 35 people. The examined group (15 persons, mean age 71,3) consisted of healthy elderly people. The reference group was formed with younger healthy people (20 persons, mean age 55).

RESULTS

Erythrocyte membrane lipid peroxidation was found stronger in the group of elderly people. Erythrocyte internal microviscosity was significantly higher in the elderly. The activity of ATPase, both total and Na(+)K(+)-dependent, appeared remarkably greater in the group of younger people. Stronger membrane lipid damage was observed in older age group, which may be implied by lower--SH group concentration, and higher W/S parameter value.

CONCLUSION

The obtained results reveal that in elderly people the intensification of oxidative stress in the entire body occurs, which may be confirmed by structural and functional oxidative erythrocyte damage. This conclusion may be significant for pathogenesis of many diseases in this period of life.

Process of nursing as an active form nurse's work with patient in therapeutic team--project of evidencing the process of looking after a sick person for students of nursing Faculty of Health Sciences, UMK Collegium Medicum in Bydgoszcz

In years sixtieth in U.S.A. the process of nursing was introduced to the contemporary practice of nursing. U.S. was also the first country where the need of teaching the nurses on high standard was noticed and executed. In years 1960-1980 a very intensive development of nursing appeared there, the process of nursing strengthened it's position as a work method based on the theory of human's needs. In Poland idea of process of care developed from over twenty years. Instruction cares is based for scientific bases this of process. Process of nursing as dynamic work method, makes a work of nurse very active and raises the quality of care after a sick person. This process embraces with one's own range also healthy man, potentially threatened with disease, family, group of persons and environment. It is the modern form of nursing in the contrary to nursing understood in traditional way. The main purpose of introduction the process of evidencing to execution of classes like geriatrics and geriatric nursing with students of the third year Faculty of Health Sciences, UMK Collegium Medicum was moulding abilities of conducting the process looking after a sick person by students trough underlining the meaning of scientific bases of nursing.

Effect of vitamin E and vitamin C supplementation on antioxidative state and renal glomerular basement membrane thickness in diabetic kidney

The aim of this study was to analyze the effect of vitamins C and E on malondialdehyde (MDA) content and activities of key antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) as well as glomerular basement membrane (GBM) thickness in streptozotocin-induced diabetic kidney in rats. Wistar male rats were divided into following groups (12 rats each): the control, diabetic rats, diabetic rats whose drinking water was supplemented with vitamin C in a dose of 1.0 g/l or diet was supplemented with 200 mg of vitamin E/100 g fodder. Body weight, blood glucose and HbA1C levels and 24-hour urinary albumin excretion (UAE) were studied every week (0-12 weeks). After 6 and 12 weeks, MDA content and activities of SOD, CAT and GSH-Px were measured in the kidney homogenate supernatants. Electron micrographs of glomeruli were scanned and morphometric investigations were performed by means of computer image analysis system to compare GBM thickness. The blood glucose and HbA1C concentrations and UAE in diabetic rats were significantly higher than in the control group. An increase in the MDA level and decrease in the SOD, CAT and GSH-Px activities in the kidney of diabetic rats were observed after 6 and 12 weeks of experiment. Administration of vitamins C and E did not affect body weight, blood glucose and HbA1C levels. Both vitamin C and vitamin E decreased lipid peroxidation and augmented the activities of antioxidant enzymes studied in the kidneys of diabetic rats as well as reduced UAE, decreased kidney weight and GBM thickness. The results indicate the potential utility of antioxidant vitamins in the protection against the development of diabetic nephropathy.

The effect of verapamil on the antioxidant defence system in diabetic kidney

BACKGROUND

The aim of this study was to examine the effect of verapamil (VP) on lipid peroxidation and activities of key antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px); as well as on glomerular basement membrane (GBM) thickness in streptozotocin-induced diabetic kidney in rats.

METHODS

Wistar male rats were divided into three groups, 12 rats each: the control (C), diabetic rats (DR), and DR receiving VP, 7 mg/kg body weight in drinking water (DR + VP). Blood glucose (BG) and HbA(1c) levels, 24-h urinary albumin excretion (UAE) and body weight (BW) were measured every week (0-12 weeks). After 6 and 12 weeks, the animals were sacrificed and malondialdehyde (MDA) content and activities of SOD, CAT and GSH-Px were determined in the kidney homogenate supernatants. Electron micrographs of the glomeruli were scanned and morphometric investigations were performed by means of a computer image analysis system to compare the glomerular basement basal membrane (GBM) thickness.

RESULTS

The levels of BG, HbA(1c) and UAE in DR were significantly higher than in the C group. A progressive increase in the MDA level and a decrease in the SOD, CAT and GSH-Px activities in the kidney of DR were observed after 6 and 12 weeks. VP administration did not affect BW changes, BG and HbA(1c) levels in DR. VP decreased lipid peroxidation and augmented the activities of antioxidant enzymes studied in the kidneys of DR as well as decreased kidney weight, GBM thickness and albuminuria in DR.

CONCLUSIONS

These results confirm the role of oxidative stress in the development of diabetic nephropathy and point to the possible antioxidative mechanism of the nephroprotective action of VP.

Effect of angiotensin convertase inhibitors and AT1 angiotensin receptor antagonists on the development of oxidative stress in the kidney of diabetic rats

The aim of this study was to analyse the effect of angiotensin convertase inhibitor, enalapril (ENA), and angiotensin AT-1 receptor antagonist, losartan potassium (LP), on lipid peroxidation and activities of Cu,Zn-superoxide dismutase, catalase and glutathione peroxidase in kidneys of streptozotocin (STZ)-induced diabetic rats after 6 and 12 weeks of treatment. STZ-induced body weight changes and blood glucose concentration were not affected by either ENA or LP but both drugs significantly decreased cholesterol and triglyceride concentrations elevated in diabetic rats, inhibited kidney weight gain, and decreased albuminuria. Kidneys of STZ-diabetic rats had increased malondialdehyde content and decreased activities of antioxidant enzymes (Cu,Zn-superoxide dismutase, catalase and glutathione peroxidase). Both ENA and LP decreased lipid peroxidation and augmented the activities of antioxidant enzymes studied in the kidneys of diabetic rats. These results confirm the role of oxidative stress in the development of diabetic nephropathy already at early stages of the development of diabetes and point to the possible antioxidative mechanism of the nephroprotective action of ENA and LP.

Effect of aminoguanidine on lipid peroxidation and activities of antioxidant enzymes in the diabetic kidney

The aim of this study was to examine lipid peroxidation and activities of key antioxidant enzymes in kidneys of rats with streptozotocin (STZ)-induced diabetes and the effect of aminoguanidine on diabetes-induced alterations. Three groups, 6 rats each, were studied: control animals, not treated diabetic rats and rats treated with aminoguanidine (AG; 1 g/liter of drinking water). After 6 and 12 weeks the animals were sacrificed and lipid peroxidation products and activities of antioxidant enzymes were determined in their kidney homogenates. Malondialdehyde (MDA) content was significantly elevated and activities of SOD and catalase decreased in the kidneys of STZ-diabetic rats. AG treatment attenuated the increase in MDA content and diminutions of activities of SOD and catalase in the kidneys of diabetic rats. These results confirm oxidative stress in the kidney of rats with STZ diabetes and point to an antioxidant effect of AG in experimental diabetes.

Effect of angiotensin convertase inhibitors on lipid peroxidation and peroxyl radical-trapping capacity in rats with experimental diabetes

Effect of two angiotensin convertase inhibitors, enalapril and captopril, on blood plasma and erythrocyte lipid peroxidation and plasma peroxyl radical-trapping capacity was studied in rats with streptozotocin-induced diabetes. A progressive increase in blood erythrocyte malondialdehyde (MDA) level was observed in diabetic rats after 6 and 12 weeks. Blood plasma MDA level increased while plasma peroxyl radical-trapping capacity was decreased after 12 weeks. Captopril (2 mg/kg body weight) augmented the diabetes-induced changes in MDA content after 6 weeks and prevented them after 12 weeks increasing also the peroxyl radical-trapping capacity. Enalapril (1 mg/kg body weight) counteracted the diabetes-induced changes in MDA content after both 6 and 12 weeks but did not affect the plasma peroxyl radical-trapping capacity. These results suggest a possibility of a therapeutic use of angiotensin convertase inhibitors to attenuate the effects of oxidative stress in diabetes.

Free radicals generation by granulocytes from men during bed rest

Phagocytes (granulocytes and macrophages) are one of the most important sources of reactive oxygen species (ROS) in the human body. A stimulated phagocyte reaches within a dozen of seconds the functional state known as the respiratory burst. This phenomenon includes three interrelated processes: 1) a several fold increase in the oxygen uptake, 2) generation of large amounts of ROS, and 3) stimulations of glucose metabolism via the pentose phosphate shunt. The main ROS generated during phagocytosis is the superoxide radical anion O2-. The reaction of dismutation of O2- generates hydrogen peroxide (H2O2). O2- and H2O2 do not have strong cytocidal proerties but are supbstrates for the generation of more active biologically ROS, especially the hydroxyl radical (OH) and hypochlorous acid (HOCl). A stimulated phagocyte (especially neutrophil) generates also vast amounts of nitric oxide (NO-). NO- may react with the superoxide radical anion forming peroxynitrate (ONOO-). Reactivity of ONOO- is comparable to that of the hydroxyl radical. ONOO- plays probably a very important role in the so-called oxygen-dependent killing mechanisms during phagocytosis. The role of NO- in the process of phagocytosis is unclear. However, NO-, apart from other biological functions, inhibits aggregation and adhesion of blood platelets. Morevover, it seems to participate in the slefregulation of granulocyte cativity (probably limiting excessive inflammative reaction). Excess of ROS generated by phagocytes may damage biologically important macromolecules. Membrane lipids are particularly vulnerable to peroxidation. It leads to alterations in membrane fluidity and permeability. ROS excreted to the environment of a phagocyte may impair functions of other morphotic elements of blood (erythrocytes and thromobcytes) in this way. Bed rest covers two conditions: 1) limitation of motoric activity (hypodynamia) and 2) restraining the pressure on bones along parallelly to their long axes (hypogravia). Under bed rest conditions organism is subject to many harmful changes. I.a., bed rest affects also leukocyte functions. However, we were not aware of any sutdies concerning the effect of bed rest on the respiratory burst of granulocytes. This study was aimed at an examination of the effect of bed rest on the generation of O; and H2O2 by neutrophils (PMNL).

Effect of long term bed rest in men on enzymatic antioxidative defence and lipid peroxidation in erythrocytes

Bed rest is an integral part of treatment of numerous diseases. Typical examples are bone fractures of lower extremities and pelvis. Temporary immobilization is necessary also, e.g., in heart diseases (stroke), backbone and imminent abortion. The sick organism spares energy during the bed rest wich is beneficial. However, bed rest results in many alterations which are disadavantageous. They concern the function of almost all organs and systems but affect most significantly the locomotor and ciruclatory systems. Bed rest brings also about changes in the composition of peripheral blood and functions of the morphotic elements of blood. Red blood cells are subjected to the action of large amounts of reactive oxygen species (ROS). During oxidation of hemoglobin to methemoglobin superoxide radical anion (O2-) is formed: HbFe2+ + O2 --> MetHbFe3+ + O2- (1) Ferrous and ferric ions present in the cytoplasm of red blood cells may be catalysts of the Fenton reaction leading to the production of the hydroxyl radical: O2- + Fe3+ --> O2- + Fe2+ (2) Fe2+ + H2O2 --> Fe3+ + OH + HO- (3) OH shows a tremendous reactivity. It may react with lipids, proteins, nucleic acids and carbohydrates. The process of lipid peroxidation is best understood. It concerns mainly polyunsaturated fatty acids present in cell membranes. Peroxidation of membrane lipids decreases membrane fluidity and impairs its barrier function. The lowered membrane fluidity compromises erythrocyte deormability which in turn disturbs oxygen delivery to the tissues. End productions of lipid peroxidation are low-molecular wieght compounds, among them carbohydrates (ethane and pentane) and aldehydes, e.g. malondialdehyde (MDA). MDA concentration is an acknowldeged marker of the intensity of lipid peroxidation. Erythrocytes contain a complex system of protection against the action of ROS. It includes various enzymatic and non-enzymatic mechanism. The most important antioxidative enzymes of the red blood cells are superoxide dismutase (Cu,Zn-SOD, EC 1.15.1.1) catalase (CAT, EC 1.11.1.6) and glutathione peroxidase (GSH-Px, EC 1.11.1.9). Cu,Zn-SOD catalyzes the dismuation of O2- to hydrogen peroxide (H2O2). Catalase and peroxidase remove H2O2 and, moreover, GSH-Px can reduce lipid peroxides. Under normal conditions an equilibrium exists between the formation and removal ROS. If ROS are formed in excess or the defensive antioxidative mechanism are inefficient, oxidative stress develops. Derangement of the equilibrium between the formation and removal of ROS is important in the pathosgenesis of many diseases, e.g. atherosclerosis, diabetes, Down syndrome and Alzheimer disease. There are literature data on disturbances of enzymatic antioxidant defense mechanism of blood plateless during bed rest. This study was aimed at an examination of the post-traumatic bed rest on the enzymatic antioxidative defense mechanisms and lipid peroxidation in erythrocytes.

Effect of the H2 histamine receptor antagonist on oxygen metabolism in some morphotic blood elements in patients with ulcer disease

BACKGROUND/AIMS

Our investigations was carried out in order to examine the effect of cimetidine, ranitidine and famotidine on the generation of free radicals, lipid peroxidation and enzymatic antioxidative defense in the blood of patients with peptic ulcer disease, clinically diagnosed as gastric or duodenal ulcer.

METHODOLOGY

124 non-smoking males (aged 20-51 years), were randomly divided into 4 groups: 28 patients received intravenously 200 mg of cimetidine; 26 patients intravenously 50 mg comprised of ranitidine; 25 patients received intravenously 20 mg of famotidine; and 45 healthy men served as the control group. Superoxide dismutase activity, malonyldialdehyde concentration in blood platelets and superoxide anion generation in granulocytes were determined in all examined men. An assay of superoxide dismutase activity and malonyldialdehyde concentration were performed before drug administration and after 2 and 72 hours. Superoxide anion generation was estimated before drug administration and after 2 hours.

RESULTS

Our data indicate that all examined H2 receptor antagonists stimulate superoxide dismutase activity, but after 72 hours a distinct increase was observed, in addition to a decrease of malonyldialdehyde concentration. No differences have been observed in superoxide anion generation in patients with ulcer disease or in healthy subjects before and after ranitidine and famotidine administration. Only after 2 hours of cimetidine administration was a significant increase in superoxide anion generation observed.

CONCLUSION

We concluded that H2 receptor antagonists have a beneficial effect on antioxidative processes.

Oxygen metabolism in blood of patients with gastric and duodenal ulcer disease

Among multiagent mechanisms causing peptic ulcer disease, oxygen free radicals hypothesis is reasonable. Our investigation concerned the determination of oxygen free radicals generation lipid peroxidation and enzymatic antioxidative defense in blood of patients with peptic ulcer disease. The examinations were performed in 79 males, non-smokers, aged 20-51 with peptic ulcer disease, clinically diagnosed as gastric or duodenal ulcer. Biochemical investigations were carried out on blood platelets obtained from venous blood according to the centrifugation fractionation technique. Superoxide dismutase (CuZn-SOD) (EC 1.15.1.1.) activity and malonyl dialdehyde (MDA) concentration were determined according to Misra and Fridovich (1972) and Placer et al (1966) methods, respectively. Oxygen free radicals as the superoxide anion O2- generation in blood according to Bellavite et al. (1983) method was determined. The results indicate that patients with peptic ulcer disease have a higher level of malonyl dialdehyde in blood platelets, whereas the superoxide dismutase activity is significantly decreased in comparison with the control group. Oxygen free radicals generation both in patients with peptic ulcer disease as in healthy men is maintained at normal level. Our data suggest that in spite of similar range of oxygen free radicals generation both in patients with peptic ulcer disease and healthy men, the injury to patients by superoxide anion is more destructive and harmful to cells, because the enzymatic antioxidative defense is decreased. The increase of lipid peroxidation in patients with peptic ulcer disease also supports this conclusion.

Effects of submaximal physical exercise and immobilization in bed on the adenine nucleotides concentration in human blood platelets

The effects of submaximal physical exercise (75% VO2max) and one month immobilization in bed on the adenine nucleotides concentration in human blood platelets were studied and compared. We have shown that after submaximal exercise and after immobilization in bed the concentrations of adenine nucleotides in blood platelets mainly ATP and ADP were decreased and probably caused by the stimulation of platelet secretory process. Thrombin which stimulated the release of 58.2% +/- 1.5% of total adenine nucleotides from control platelets, liberated decreased amounts of nucleotides from platelets after physical exercise and after immobilization in bed (39.9 +/- 2.1% and 23.6 +/- 2.03% of total, respectively).

Changes in antioxidant enzymes activities, aggregability and malonyldialdehyde concentration in blood platelets from patients with coronary heart disease

In 41 patients with coronary heart disease (CHD) the concentrations of total blood platelet malonyldialdehyde (MDA: 2.11 +/- 0.25 nmol/10(9) platelets) and MDA corresponding to thromboxane A2 (TXA2 0.84 +/- 0.13 nmol/10(9) platelets) were increased in comparison with values in blood platelets of healthy subjects (1.19 +/- 0.09 and 0.71 +/- 0.05 nmol/10(9) platelets), respectively. The increased aggregability with ADP and thrombin of patient platelets was also observed. In relation to the blood platelets of healthy subjects, the antioxidant enzymes activities of patient blood platelets were significantly (P < 0.001) decreased. Platelet glutathione peroxidase (GSH-Px) activity of the patients (11.3 +/- 0.85 U/g protein) was significantly lower than controls (18.3 +/- 1.12 U/g protein). In patients with CHD the activities of the other antioxidative platelet enzymes: catalase (Cat, 7.37 +/- 1.38 U/g protein) and superoxide dismutase (SOD, 1529.4 +/- 167 U/g protein) were also significantly decreased in comparison with values for healthy subjects (Cat: 9.06 +/- 1.30 U/g protein and SOD: 1987 +/- 230 U/g protein, respectively). It is suggested that antioxidative defense in blood platelets may affect the haemostatic processes and lipid peroxidation in patients with CHD.

[Effect of cimetidine on the heart conduction system]

An effect of cimetidine on ECG records has been investigated in a group of 40 patients with gastric or duodenal ulcers and coexisting circulatory disorders. For this purpose ECG has been recorded with Holter's technique (Medilog 2000) together with ECG-recording using high amplifying technique. An intravenous injection of 200 mg of cimetidine produced in some of patients inhibition of the sinus rhythm atrio-ventricular conduction disturbances as well as changes in the end phase of ECG ventricular image. The authors suggest, that intravenous administration of cimetidine to patients with cardiac diseases should be monitored with ECG recording.