The effects of neurotensin on selected parameters of lipid metabolism in rats.

15 nM/kg b.m. of neurotensin (NT) caused a significant inhibition of LMA within 30 min of administration and this effect persisted up for to the 240 th minute of the experiment. A 15 nM/kgb.m. dose also caused a reduction in SLA which persisted up to the 120 th minute. Sixty minutes after an intraperitoneal administration of NT a decrease in the cholesterol and NEFA levels and an increase in the TG and glycerol levels were observed. These effects were inhibited by the NTR2-blocker (levocabastine) and were not subject to change after an in vivo application of SR 48692.

The effect of bradykinin on the oxidative state of rats with acute hyperglycaemia.

Many clinical and experimental studies have established the beneficial effect of kinins in hypertension, heart failure and ischaemia-reperfusion syndrome, but little attention has been given to the role of kinins in hyperglycaemic conditions. The purpose of the present study was to determine the influence of bradykinin on the levels of glucose, insulin, malondialdehyde and hydrogen peroxide, as well as antioxidative enzyme activity in rats with streptozotocin (STZ)-induced acute hyperglycaemia. In STZ-induced hyperglycaemic rats the levels of glucose, hydrogen peroxide and malondialdehyde were increased by 256% (from 6.0+/-0.3 to 21.4+/-1.3 mmol/l, P<0.001), 33% (from 1.9+/-0.1 to 5.6+/-0.3 mmol H(2)O(2)/ml, P<0.001) and 19% (from 3.7+/-0.3 to 4.9+/-0.2 nmol/l, P<0.001) respectively. The activity of superoxide dismutase, catalase and glutathione peroxidase and the level of insulin were decreased by 46% (from 1367+/-73 to 737+/-59 U/g Hb, P<0.001), 36% (from 2.3+/-0.3 to 1.4+/-0.1 U Bergmayera/g Hb, P<0.001), 31% (from 236+/-19 to 163+/-24 U/g Hb, P<0.001) and 91% (from 47.5+/-1.7 to 2.4+/-0.5 mU/l, P<0.001) respectively in rats treated with streptozotocin. The administration of bradykinin caused the decrease in glucose, hydrogen peroxide and malondi-aldehyde levels by 38% (from 21.4+/-1.3 to 13.3+/-1.0 mmol/l, P<0.001), 37% (from 5.6+/-0.3 to 4.3+/-0.2 mmol H2O2/ml, P<0.001), 39% (from 4.9+/-0.2 to 3.0+/-0.2 nmol/l, P<0.001) respectively and the increase in insulin level and superoxide dismutase, catalase and glutathione peroxidase activity by 62% (from 2.4+/-0.5 to 4.0+/-0.4 mU/l, P<0.001), 23% (from 736.8+/-58.5 to 906.7+/-47.8 U/g Hb, P<0.001), 23% (from 1.4+/-0.1 to 1.9+/-0.1 U Bergmayera/g Hb, P<0.01) and 19% (from 163.1+/-23.6 to 202.3+/-11.7 U/g Hb, P<0.001) respectively in rats with hyperglycaemia. Thus, bradykinin is able to reduce oxidative stress in hyperglycaemic conditions.

[The level of erythropoietin in serum of patients with anemia during infective endocarditis]. / Stezenie erytropoetyny w surowicy krwi u pacjentów z niedokrwistoscia w przebiegu infekcyjnego zapalenia wsierdzia.

The infective endocarditis is a septic syndrome caused by an infection in endocardium or in heart valves. The majority of patients with infective endocarditis develop normocytic anemia. The metabolic studies in septic shock syndromes documented an intensive proteolysis of muscles, visceral organs and blood proteins, and probably of erythropoietin as a glycoprotein as well. The aim of the study was to assess the erythropoietin level in patients with infective endocarditis severe anemia and preserved renal function. Erythropoietin concentration was measured in blood serum in 12 patients (11 men and 1 woman), mean age 48 +/- 8 years, with infective endocarditis. The patients had clinical symptoms of endocarditis, positive blood bacteriological cultures and echocardiography features. All patients had serious normocytic anemia with mean hemoglobin concentration 5.40 +/- 0.48 mmol/L. The control group consisted of 7 healthy persons (5 men and 2 women), mean age 50 +/- 7 years, with hemoglobin concentration 8.70 +/- 0.60 mmol/L. The concentration of erythropoietin at the patients with bacterial endocarditis was 144.04 +/- 17.80 mIU/mL versus 67.28 +/- 6.29 mIU/mL in the control group (p = 0.0002). We conclude that in patients with infective endocarditis and serious normocytic anemia without renal insufficiency the concentration of erythropoietin is increased.

[Neurotensin--structure, origin and biological function]. / Neurotensyna--budowa, miejsce wystepowania i dzialanie biologiczne.

Neurotensin is a 13-amino acid hormonal peptide which was first isolated from bovine hypothalamus. It is present in the digestive tract as well as in the central nervous system. It has a variety of biological activities as a central neurotransmitter or neuromodulator, and a peripheral hormone. NT receptors have been characterized in a variety of tissues and cell lines of peripheral and central organs. The physiological functions of NT include stimulation of pancreatic and biliary secretion, stimulation of colonic motility, inhibition of small bowel and gastric motility, trophic effect on numerous tissues of the gastrointestinal tract. NT exerts hypothermic and analgesic effect when injected into the central nervous system. From a clinical standpoint, studies with NT have led to implications of its involvement in schizophrenia, Parkinson's disease and Alzheimer's disease.

[Lipid mobilizing activity in blood serum during the follicular and luteal phases of the menstrual cycle]. / Aktywnosc mobilizujaca lipidy surowicy krwi w fazie folikularnej i lutealnej cyklu miesiaczkowego.

The lipid mobilising activity of woman's blood serum in the follicular and luteal phases has been investigated. This activity was determined according to the Buckle method concerning parametrial adipose tissue of female rats. It was found to enhance the lipid mobilising activity in the follicular phase of the menstrual cycle. The increment of the lipid mobilising activity in the luteal phase was lower than in the follicular phase.

Effect of hypothermia on the insulin--receptor interaction in liver plasma membranes.

The aim of the study was to estimate the effect of hypothermia on (125J)-iodoinsulin binding to liver plasma membranes. Rat liver membranes were prepared from control, normothermic rats (Tr = 35.6 +/- 0.3 degrees C) and hypothermic rats (Tr = 26.5 +/- 0.9 degrees C) and purified according to Havrankowa. In addition, serum insulin and glucagon levels by means of RIA and glucose concentration using the glucose oxidase method were measured. Scatchard analysis was used to determine the kinetic parameters of the hormone receptor interaction. The data showed no significant differences in the affinity of the binding sites but indicated a decrease in receptor concentrations in liver plasma membranes from hypothermic rats. In contrast to changes in serum insulin level which was decreased by about 50% in hypothermic rats blood glucose concentrations did not significantly differ between the hypothermic and normothermic ones. Our results show that in hypothermic rats the hormonal adaptation operates on the level of the number of liver receptors whereas the insulin receptor affinity remains unaffected.

[Effect of insulin on temperature and metabolic responses in rats during normothermia and hypothermia]. / Wplyw insuliny na odpowiedz temperaturowa i metaboliczna u szczurów w przebiegu normotermii i hipotermi.

As shown in our previous study, hypothermia provokes a variety of hormonal changes including inhibition of insulin secretion and increase in blood serum glucagon level. According to Therminarias et al. the administration of exogenous insulin to dogs subjected to hypothermia causes a calorigenic effect by enhancing oxygen consumption and rising the intensity of shivering thermogenesis. The study was aimed at establishing whether exogenous insulin administered to rats subjected to brief hypothermia and having the shivering thermogenesis blocked by thiobutabarbital anesthesia can influence rectal temperature, the levels of some hormones and energy metabolism. The results obtained suggest that 1) insulin administration causes an increase in the energy charge potential (ECP) both in the liver and in skeletal muscle of the rat, indicating the domination of anabolic processes both in normothermic and hypothermic conditions, 2) there is a negative correlation between the levels of insulin and free fatty acids and the activity of isocitric dehydrogenase in rat liver mitochondria, and 3) the administration of insulin at a dose provoking metabolic response both in normothermic and hypothermic conditions was ineffective in provoking temperature response, indicating the existence of a functional dissociation between the various effects of the same dose of exogenous insulin.

[Effect of progesterone on lipolysis in blood and adipose tissue of the female rat]. / Wplyw progesteronu na procesy lipolityczne we krwi i tkance tluszczowej samicy szczura.

The effect of progesterone on lipolysis in blood and in adipose tissue of female rats has been investigated. The hormone was administered to the studied animals subcutaneously during 20 days. The lipid mobilizing activity was determined in blood serum according to the four experimental protocols: test serum--test tissue, test serum--control tissue, control serum--test tissue, and control serum--control tissue. Blood serum concentrations of triglycerides, free fatty acids and glucose, as well as lipolytic activity against exogenous substrate, were determined in addition. Progesterone administration was found to enhance the activity of factors potentiating lipolysis in adipose tissue of female rats after 20 days administration of the hormone. There was an increase in free fatty acids, triglycerides and glucose concentrations. Progesterone was found not to change the activity of factors influencing lipolysis in the blood of female rats during the period of administration of the hormone.

[Effect of tolbutamide on lipolytic processes in blood and fat tissue of rats maintained in normothermic and hypothermic conditions]. / Wplyw tolbutamidu na procesy lipolityczne we krwi i tkance tluszczowej szczurów przebywajacych w warunkach normotermii i hipotermii.

The effect of tolbutamide administered in vivo or added to the incubation medium on lipolysis in adipose tissue and in blood has been studied in rats. Tissue lipolysis was lowered by 118 to 156% in groups of rats receiving tolbutamide in vivo. The addition of tolbutamide directly to the incubation medium caused an increase in the lipid mobilizing activity, while the addition of insulin inhibited lipolysis in each case. The effect of tolbutamide administered in vivo may be indirect through an increase in insulin binding and/or the drug may influence directly the permeability of cell membrane for ions and glucose. An increase in the lipid mobilizing activity observed in experiments consisting in the addition of tolbutamide to the incubation medium may be linked to the low glucose level and greater demand for free fatty acids or to the low level of insulin in the incubation medium.

In vivo effect of 2-deoxy-D-glucose on glucose-6-phosphate dehydrogenase activity in the cytosol of liver, heart and skeletal muscle of rats.

2-deoxy-D-glucose (2-DG), the unmetabolizable analogue of glucose induces a series of metabolic, hormonal and behavioral responses, causing cellular glucoprivation. According to in vitro studies, 2-DG inhibits phosphofructokinase in cultured human cells. The present investigations deal with changes in the cytosolic glucose-6-phosphate dehydrogenase activity following in vivo 2-DG administration. A single dose of 2-DG (600 mg/kg) has no influence on the activity of glucose-6-phosphate dehydrogenase in the cytosol of liver, heart and skeletal muscle of the rat. The concomitant increase in serum glucose, lactate and FFA concentrations observed in the study indicates indirectly a stimulation of adrenergic system. After three days of successive administration of 2-DG to rats, dehydrogenase activity decreased in the liver by approx 57% and in the skeletal muscle by approx 82% in comparison with control animals. Moreover the in vivo effect of 2-DG was found to be fully reversible, probably when the total amount of the inhibitor was excreted.

In vivo effect of 2-deoxy-D-glucose on adenine nucleotide levels in the liver and skeletal muscle of rats.

The present report indicates that 2-deoxy-D-glucose (2-DG) at a single dose causing reduction of Tre has no influence on liver and skeletal muscle content of ATP, ADP and AMP, the ATP/ADP ratio, energy charge potential (ECP) and total adenine nucleotides (TAN). After administration of 2-DG for 3) successive days, the level of ATP, ATP/ADP ratio, the values of ECP and TAN are decreased both in the liver and skeletal muscle. However, 72 hours after the last injection of 2-DG adenine nucleotide contents returned to the values observed in control group, indicating that the in vivo effect of this glucose analogue is fully reversible.

The effect of 4-aminopyrazolo (3,4-d) pyrimidine (4-APP) on some parameters of carbohydrate metabolism in the rat.

The study was designed to evaluate some parameters of carbohydrate metabolism in the rat as influenced by 4-APP, an adenine analogue. Adult female rats were injected with 1 mg 4-APP/100 g body weight/day for 3 days. 4-APP evoked a marked enlargement of the liver with lipid droplets accumulation in hepatocytes. This was accompanied by a marked lowering of the liver glycogen content. Within 3 days 4-APP did not change serum glucose, insulin and free fatty acid concentration. Serum glycogenolytic activity studied in an in vitro system showed 7 times as high glucose releasing ability in 4-APP treated rats as that of the serum of control animals. 4-APP resulted also in a marked enlargement of the adrenal medulla and lowered adrenaline and noradrenaline concentrations in the gland. The possibility of an activation of glycogenolysis in the liver of 4-APP treated rats has been discussed.

[Effect of estradiol on lipolytic processes in the blood and adipose tissue of female rats]. / Wplyw estradiolu na procesy lipolityczne we krwi i tkance tluszczowej samicy szczura.

The effect of estradiol on lipolysis in blood and in adipose tissue of female rat has been investigated. The hormone was administered to the studied animals subcutaneously during 20 days. The lipid mobilizing activity was determined in blood serum according to the four different experimental protocols: test serum--test tissue, test serum--control tissue, control serum--test tissue, and control serum--control tissue. Blood serum concentrations of triglycerides, free fatty acids and glucose, as well as lipolytic activity against exogenous substrate, were determined in addition. Estradiol administration was found to enhance the activity of factors potentiating lipolysis both in the blood and in adipose tissue of female rats, inasmuch as an increase in free fatty acids and triglyceride concentration, and a decrease in glucose concentration were observed during the period of administration of the hormone.

Triiodothyronine effect on some parameters of carbohydrate metabolism in rat blood and liver. I. In vivo effect of triiodothyronine on liver glycogen content, blood metabolites and serum glycogenolytic activity.

Short (7 days) T3-treatment has no influence on the plasma glucose and FFA concentration and blood lactate level, as well as on the hepatic glycogen content in the rats. The rise in T3 levels, observed in our study, was accompanied by a fall in T4 concentrations, indicating suppression of the endogenous T4 production. On the other hand, glycogenolytic activity of rat serum in vitro is the highest in the system: control liver slices-serum of rats pretreated with T3 as compared to the system: control liver slices-control serum. These observations may lead to conclusions, that serum of rats pretreated with T3 contains factors exhibiting the greater ability to mobilize glucose from liver slices than the control serum (euthyroid). The possibility, that pretreatment with T3 may cause a decrease in the number and/or affinity of beta-adrenergic receptors in the rat liver, is discussed.

Hyperthermia effect on lipolytic processes in rat blood and adipose tissue.

Rats anaesthetized with Brevinarcon were placed in a high-temperature chamber (air temperature 50 degrees C, relative humidity 50%) for induction of hyperthermia (rectal temperature 41.0 +/- +/- 0.5 degrees C). The control group comprised rats anaesthetized in the same way but kept at room temperature. In the serum in both groups glucose, free fatty acids, immunoreactive insulin, lipolytic activity and ability to mobilize lipids in vitro were determined. It was shown that the glucose and free fatty acid levels and the activity mobilizing serum lipids in vitro in the rats subjected to hyperthermia were lower than in the control group by 12%, 23% and 150% respectively. The lipolytic activity of the serum of rats subjected to hyperthermia was 42% higher, and the level of immunoreactive insulin rose by about 224% in relation to the control group. These results point to inhibition of lipolysis in the adipose tissue with simultaneous activation of intravascular lipolysis during hyperthermia in rats.

Adrenocortical function in 4-APP treated rats: a coupled stereological and biochemical study.

Adrenocortical function in 4-APP-induced (4-aminopyrazolo[3,4-d]pyrymidine) lipoprotein-deficient rats was studied in relation to quantitative morphologic changes in the gland. 4-APP treatment results in enlargement of the adrenal cortex and its zona fasciculata and reticularis cells. In enlarged livers, cholesterol and free fatty acid concentrations were similar to that of control rats, however a marked accumulation of triglycerides with a concomitant drop in hepatic delta 4-steroid hydrogenase activity was found. A profound drop in serum cholesterol in both, high and low density lipoproteins, as well as triglycerides and plasma corticosterone concentrations was accompanied by a marked lowering of cholesterol and corticosterone concentration in the adrenal gland. Corticosterone output by adrenal homogenates was higher in 4-APP treated rats than in control animals. Such a treatment did not change cholesterol side-chain cleavage, 11 beta-hydroxylase, 3 beta-ol dehydrogenase-isomerase, steroid 5 alpha-reductase and neutral lipase activities when expressing results per unit weight of tissue or protein. However, when calculating per adrenocortical cell, adenine analogue applied increased 11 beta-hydroxylase, steroid 5 alpha-reductase and neutral lipase activities. Thus, coupled biochemical and stereologic studies revealed a complex and multidirectional effect of 4-APP on the rat adrenal cortex. This effect may be caused by serum lipoprotein deficiency and by toxic and stressful action of the adenine analogue on the rat. Also a direct effect of 4-APP on rat adrenal cortex may not be excluded.

[Energy expenditure and work exertion in clothing industry workers]. / Koszt energetyczny i ciezkosc pracy robotników przemyslu odziezowego.

The maximum oxygen uptake (VO2max), oxygen consumption compared with VO2max values--percent of VO2max (strenuousness) and energy expenditure in clothing industry workers were investigated. Seventy five subjects took part in those investigations. The effective energy expenditure of weedle women was 2,3 KJ/480 min, store-workers--3,3 KJ/480 min, cutters 4,8 KJ/480 min, layers--5,1 KJ/480 min, and ironers from 3,7 KJ/480 min, to 4,7 KJ/480 min, respectively.

Effect of 2-deoxy-D-glucose on lipolytic processes in blood and adipose tissue of rat.

The effect of 2-deoxy-D-glucose on lipolytic processes in the blood and adipose tissue was studied. Rats treated with this antimetabolite showed a significant increase in serum glucose, FFA and glycerol level, as well as in the lipid mobilizing activity. On the other hand, the lipolytic activity of rat serum decreased when compared to control group. From these results it may be concluded that during hypothermia induced by administration of 2-deoxy-D-glucose intracellular, but not intravascular, lipolysis is enhanced.