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The present experiment was undertaken to investigate the possible involvement of GABAergic neurons in the regulation of the feeding behavior induced by tail pinching. Injections before the tail pinching of gamma-aminobutyric acid (GABA) agonist (Muscimol: 570 micrograms.kg-1 i.p. 20 min before testing), GABA antagonist (Picrotoxine: 1,5 mg.kg-1 i.p. 30 min before testing) and a GABA transaminase inhibitor (Acetate dipropyle: 200 mg.kg-1 i.p. 40 min before testing) have no effects on the ingestion of sweet milk. These preliminary results provide support for the hypothesis that the feeding behavior induced by TP is not mediated through GABAergic system.

The urinary catecholamines output and the food intake were investigated in two groups of rats: a control group and a group where Tail Pinches (T.P.) were performed. Our results have shown, as these of antelman and al., that the Tail Pinch induced a high concentrate milk consumption, in spite of an increase of adrenergic activity which is known to have an inhibitory effect on caloric intake. We suggest that the role of various stress on food intake dependes on the balance of these two antagonist effects.

The effects of swimming training upon mechanical and metabolic properties of heart are investigated in two groups of male Sprague Dawley rats, fed ad libitum: a control group and a swimming group. The chronic training improves myocardial mechanical performances: coronary flow, cardiac output and left ventricular pressure are increased in isolated working conditioned heart preparations. Oxygen consumption and work performance are greater than in control group, but cardiac efficiency is not significantly different between the two groups. Intrinsic conditioned heart rate is lower than in control heart. Endogenous triglycerides and exogenous FFA utilization rates are increased in trained perfused heart. We found a significant correlation (P less than 0,01) between exogenous FFA utilisation and coronary flow.

Peroperative catecholamine levels were taken as a method for the assessment of automatic protection. Plasma adrenalin and nonadrenalin levels (spectro-fluometric technique) were measured at different pre-, per- and postoperative times in twenty eight surgical patientS: fifteen undergoing cardiac surgery and ten surgery involving the aortic bifurcation. Anaesthesia included high doses of fentanyl associated with droperidol. During aortic grafts variations in catecholamine levels were not significant, whilst during and after ECC there was a significant increase in the values. These variations were slight in comparison with those which may be seen during the excision of a phaeochromocytoma and were very similar to those obtained during effort. There were wide individual variations.

Intracellular investigation of bioelectrical properties is performed on cultivated rat myocardial cells. Electrophysiological parameters of cells dissociated from rat myocardium are very similar to those of in vivo cells. Fast sodium channels are found to be fonctional. Spontaneous arrhythmia are recorded from some impaled cells.

We studied the effects after cigarette quicksmoking in 15 subjects on plasma catecholamines levels (epinephrine and norepinephrine), on heart rate and arterial pressure. Smoking-associated increments in mean plasma norepinephrine and epinephrine as well as in heart rate and arterial pressure were demonstrated. The lack of correlation between the increase of the adrenergic system activity and this of the hemodynamic parameters can be explained by their own different characteristics.

A dietary survey has been carried out in 5 to 6, 9 to 11 and 14 to 16 years old children of the urban area of Dijon. The method was the 7 day-record with data processing by computer. The results showed that the mean caloric intakes were lower than the recommended allowances, and that the mean values of proteins (14.5%), lipids (40%) and carbohydrates (45.5%) were the same in the various age groups. Iron and calcium intakes were not sufficient in adolescent girls. The part of the breakfast was decreasing with age. Large individual variations were observed among children.

The food consumption of 543 French infants, aged 3 to 24 months, was recorded during a 3 day period. The nutrient intake data were calculated by a computerized food table. The 1981 recommended dietary amounts proposed by the Committee of the Centre National de Coordination des Etudes et Recherches sur la Nutrition et l'Alimentation were used to assess adequacy of intake. Our results showed a great variability between individuals considering the caloric intake. The mean energy intakes were greater than the recommended amounts for the age range of 6 to 12 months: therefore a revision of the recommended amounts appears necessary. A marked decrease of the consumption of infant formulas was noted between 4-5 months (57% of the total energy intake) and 6-7 months (18% of the total energy intake). The consumption of the other baby foods was the highest at 6-7 months (23% of the total energy intake). The probability that a French infant has a protein intake less than the recommended amounts was less than 0.02. This probability was 0.04 for calcium intake and 0.50 to 0.78 for iron intake according to age. An increase of the iron intake from 4-5 months is a justified dietary goal. The mean intake of linoleic acid was the smallest at a mean age of 8 to 12 months and represented less than 2% of the caloric intake.

Vitamin B1, B2, B6, C, A, and E status was assessed by combining determination of dietary intake with biochemical indices in 55 young male athletes. When compared with 20 matched sedentary controls, a similar number of individuals with biochemical deficiency was found in both groups for vitamins B1, B6, and E despite a higher mean dietary intake of these three vitamins in young athletes. Markedly reduced levels of pyridoxal 5'-phosphate, the biologically active form of the vitamin B6 compounds, were found in both populations. Supplementation administered for one month improved the vitamin status of the control subjects but not entirely those of the young athletes.

The vitamin B6 status of 60 institutionalised elderly subjects (group A: 31 men, mean age = 77 yr and 29 women, mean age = 84 yr) and 41 healthy young adults (group B or control group: 18 men, mean age = 30 yr and 23 women, mean age = 27 yr) was evaluated using erythrocyte aspartate aminotransferase activity coefficient (alpha EGOT) and plasma pyridoxal phosphate (PLP) level (vitamin B6-deficient subjects = alpha greater than 2.0 and PLP less than 80 nmol/l). The kilocalorie, protein and pyridoxine intakes were also estimated. Regarding calories and protein, the diets may be generally considered satisfactory in respect to the French 1981 RDA. The mean dietary intake of vitamin B6 was less than 2 mg/day in all groups. Ninety per cent of the aged, 80 per cent of females in group B in contrast to 56 per cent of males in group B consumed less than their individual vitamin B6 requirements as determined by a probability method. As the incidence of vitamin B6 biochemical deficiency was much higher in the group A (71% for males and 86% for females) than in the control group (11% for males and 30% for females), it is concluded that the high incidence of biochemical vitamin B6 deficiency noted in the aged appeared more relevant from an altered metabolism of the vitamin than from a too low energy intake. Supplements with high doses of vitamin B6 to aged subjects caused a significant decrease in alpha EGOT and a significant increase in PLP levels.

Plasma dopamine-beta-hydroxylase activity and catecholamines (adrenaline and noradrenaline) level in venous blood taken from the cubital vein and in arterialized capillary blood taken from the ear lobe were measured before and after a maximal exercise on a treadmill in 14 healthy untrained volunteers. The authors have shown a good correlation between these parameters in venous blood and those in capillary blood. It is concluded that the determination of plasma dopamine-beta-hydroxylase activity and catecholamines level in arterialized capillary blood could be a valid measure of the sympathetic activity.

Many experimental studies have utilized the activity of dopamine-beta-hydroxylase (DBH) as an index of sympathetic activity, since this enzyme is not submitted to uptake mechanisms or to enzymatic metabolism as are the circulating catecholamines norepinephrine (NE) and epinephrine (E). However, large discrepancies have been found between the results of these studies. The hypothesis which is examined in this study is that these discrepancies might arise from the different intensities in the stimuli utilized. In order to examine this possibility, plasma DBH activity was measured in seven subjects at rest and in three different conditions known to increase sympathetic activity to varying degrees, i.e., during hand-grip, standing, and supra-maximal bicycle exercise. Plasma NE and E concentrations were also measured during these stimuli. The results of this study show that DBH activity increases above resting levels only during supramaximal dynamic exercise, while plasma NE and E concentrations increase during each experimental condition. Furthermore, the increases in NE and E are related to each other and are also related to heart rate when all experimental conditions are considered. On the contrary, the variations in plasma DBH (expressed as a percentage of the resting value) are not related to other sympathetic indices or to heart rate. Since NE and E vary little from subject to subject at rest and increase discretely in response to the various stimuli, these plasma catecholamine concentrations therefore appear to represent the most accurate indices of sympathetic activity.

In 3 patients with proved pheochromocytoma, circulating catecholamine concentrations, vanillylmandelic acid and total free catecholamine urinary excretion, dopamine-beta-hydroxylase activities in plasma were measured the day before surgery, during the removal of the tumour and postoperatively. Following the removal of the pheochromocytoma, all these parameters declined with a different rate, possibly related to the half-life proper to each molecule. The results showing a decrease in plasma D beta H activities after the removal of the tumors are in good accordance with most authors. The mechanism and the meaning of catecholamines release from non-innervated tumor-cells remain to be elucidated. By considering these three cases, it does not seem that the evolution of D beta H activity after removal of the tumor is dependent upon the fact that the pheochromocytoma releases preferentially either epinephrine or nephinephrine.

The daily intake of vitamin B1, B2, B6, PP, C, A, D and E was investigated in 297 adult subjects, undergoing a check-up examination in a Health Center in Burgundy, by the 7-day self-recorded prospective protocol, to determine the prevalence of vitamin deficiency risks in an area of a West European Country. The daily vitamin intake was lower than the French Recommended Dietary Allowances: RDA (CNERNA, 1981). The intake was between 50 and 80% of RDA for vitamin B1 in 58%, B2 in 24%, B6 in 59%, PP in 43%, C in 21%, A in 8%, D in 0.6%, E in 53% of the female population and for B1 in 40%, B2 in 18.5%, B6 in 59%, PP in 46%, C in 27%, A in 11%, D in 7% and E in 47% of the male population. The daily vitamin intake was less than half of RDA vor vitamin B1 in 11%, B2 in 0.6%, B6 in 33%, PP in 6.3%, C in 4.5%, A in 0.6%, D in 98%, E in 36% in the females and for B1 in 3%, B6 in 8.5%, PP in 3.5%, C in 5%, A in 0.7%, D in 91% and E in 9% in the males. The use of a probability analysis for estimating vitamin deficiencies showed intakes below their own requirement in 37.8% for B1, 18% for B2, 58.6% for B6, 46% for PP, 29% for C, 8.3% for A, 98% for D and 43.4% for E in the males and 62.5% for B1, 20.9% for B2, 86% for B6, 46% for PP, 24% for C, 9.2% for A, 98% for D and 59.7% for E in the females. Significant correlations were found between the daily vitamin intake and the caloric intake for B1 (r = 0.64), B2 (r = 0.46), B6 (r = 0.64) and PP (r = 0.62). The significantly lower caloric intake in females than in males explains a higher proportion of vitamin deficiencies for B1, B2, B6 and PP in this population. The consumption of green vegetables and fresh fruit, and, consequently, vitamin C intake, was higher in females. Although it was not possible to determine to what extent the vitamin intake deficiency contributes to an impaired biochemical vitamin status, the dietary data of this study supply sufficient information to demonstrate high prevalences of deficient vitamin status in France, particularly for B1, B6 and E.

An assay method for the determination of pyridoxal 5'-phosphate (PLP) in plasma is presented. The procedure is rapid and requires only a small volume. The method includes PLP-dependent enzymatic decarboxylation of L-tyrosine to tyramine (enzyme used: L-tyrosine apodecarboxylase (EC 4.1.1.25) from Streptococcus faecalis) and measurement of tyramine by high-performance liquid chromatography with electrochemical detection. This technique confers specificity, rapidity, and low-cost measurement. Human plasma PLP from 30 normal healthy adults had a mean value of 65.10 +/- 4.70 nM. Sensitivity of the reaction was 1.3 nM and the coefficient of variation of the method (30 repeated assays of sample with a value of 60 nM) was 1.9%.

This work aims at studying the operative complications of the stabilisation of total hip arthroplasties with the help of 11 hemodynamic studies, 19 functional records of the epinephrines and 25 surveys of the impact of the stabilisation on arterial blood gas. 1) Within the few minutes following the implantation of bone cement one may remark: -- a drop in the average arterial pressure, -- greater lowering of the stroke index after a femoral implantation than after a cotyloïdal implantation, -- a constant and massive rise of pulmonary resistances which appears mainly after a femoral stabilisation. 2) The hemodynamic disturbances are accompanied by neither a significant rise nor a significant fall of the plasmatic and urinary levels of the epinephrines. 3) There appears with the insertion a massive hypoxemia which can be prevented by the inhalation of pure oxygen.

The use of sensitive detectors has enabled the development of high performance liquid chromatography (HPLC) for the dosage of plasma catecholamines (adrenalin, A; noradrenalin, NA and dopamine, DA). Separation of the catecholamines may be done with a pair of ions chromatography on grafted silica or with an exchange of ions chromatography. The quantification is carried out, either by electro-chemical detection (HPLC-ECD), or by fluorometry after catecholamines shunting into trihydroxyindoles compounds (THI). The THI method, more sensitive, does not permit the detection of DA. Plasma levels of A or NA of 30 pg/ml (or 150 fmol/ml) may be measured by HPLC-ECD). The validation of this method as compared with a radioenzymatic method (RA-COMT) permits to imagine that the HPLC-ECD method, which has the advantage of being more economical, less complex and faster than the RA-COMT method, represent a useful tool for the exploration of the adrenergic system clinically as well as in research.

Electrical properties of cultured newborn rat heart cells are investigated by the use of microelectrophysiological methods. Amplitudes of resting and action potentials appear close to those of in situ heart cells. Elevated spike rate of rise reveals functional fast sodium channels. An inconstant ratio of cells exhibit pacemaker-like activity but no relationship can be established between this automaticity and the tissular origin of the cultured cells. The pulsation rate appears to be linked to the action potential duration and to the pace-maker potential slope. Spontaneous arrhythmias may occur; they are mainly caused by anomalous conduction and (or) erratic pacemaker driving. Thus heart cell cultures may be considered as a precious tool in the field of the cardiac electrophysiologal and physiopathological studies.

The pyridoxamine (PM), pyridoxal (PL) and pyridoxol (PN) in liver, the urinary excretion of 4-pyridoxic acid (4-PA), the red blood cells enzymatic activities (aspartate aminotransferase, GOT and alanine aminotransferase, GPT) were determined in rats fed diets containing different levels of PN, HCl (0,23-170 micrograms/rat/d) during 13 days. PL and PM hepatic levels, GOT and GPT activities decreased significantly in groups A and B receiving respectively 0,23 and 11 micrograms PN, HCl/rat/d. No differences were noticed in food intake and growth. The urinary excretion of 4-PA shows a consistent trend with vitamin B6 intake. As the PM/PL-ratio was maximum in group A, PL reflects the actually available vitamer, whereas PM should be regarded as "trapped" PL. The GOT and GPT activities can be considered as reliable parameters of the pyridoxine status of the rat.

The effects of semi-liquid diets containing 6.6% in weight of refined sunflower seed oil (SSO) or hydrogenated coconut oil (HCO) on cardiac endogenous substrates and functional parameters of rats hearts were compared to a standard laboratory chow during seven days. No difference appeared for cardiac glycogen and lipid constituents. Cardiac performance, measured through left atrial perfusion was enhanced by SSO diet and HCO one altered it. A significative phospholipid depletion appeared during the 45 minutes perfusion only in the HCO group.

The plasma dopamine-beta-hydroxylase activity was measured in 10 healthy untrained volunteers during a graded physical exercise on a bicycle ergometer. The authors have shown a good correlation between the DbetaH activity and the noradrenaline content in plasma. It can therefore be concluded that the DbetaH activity could be a true measure of the sympathetic activity.