Serum phospholipids in bilharzial hepatic fibrosis and chronic active hepatitis.

The various serum phospholipid fractions were quantitated by thin layer chromatography in 33 patients with bilharzial hepatic fibrosis, 11 patients with chronic active hepatitis and 25 normal human subjects. In bilharzial hepatic fibrosis, the total serum phospholipid level showed a significant drop, while in chronic active hepatitis it was significantly elevated above the normal level of the controls. In both groups of patients, the percentage of phospholipids analyzed as lecithin was significantly elevated. The percentage of total phospholipids analyzed as sphingomyelin tended to be within the normal range of controls while the percentages of lysolecithin and cephalin fractions were significantly decreased. The increase in the relative percentage of lecithin with the simultaneous decrease of the relative percentage of lysolecithin was referred to the decrease of the lecithin-cholesterol acyl transferase enzyme activity in the plasma of these patients.

Inhibition of cholinesterase by 5-hydroxytryptamine.

On the basis of structural relationships between 5-hydroxytryptamine (5-HT, serotonine) and eserine, the effect of 5-HT on partially purified brain cholinesterase (ChE) was studied. The addition of 5-HT to brain ChE in vitro resulted in its inhibition, and the constants characterizing this inhibition, namely, the inhibition rate ki (5.44 X 10(2) mol-1/l - min-1), the equilibrium constant K (1.86 X 10(-3), and the rate constant for spontaneous reactivation kr (1.01 min-1) were determined. The inhibition of AChE by 5-HT in vitro was found to be of the competitive type.

Fatty acid composition of serum lipids in bilharzial hepatic fibrosis and chronic active hepatitis.

The fatty acid pattern of blood serum lipids was examined by gas liquid-chromatography in 30 cases with bilharzial hepatic fibrosis, 11 cases with chronic active hepatitis accompanied by jaundice, and 28 healthy individuals as a comparison group of the same socioeconomic class of patients. In addition, the fatty acid patterns of the three major serum lipid classes, namely: cholesterol ester, phospholipids and triglycerides, were also investigated in seven cases of each group by gas liquid chromatography. The most remarkable differences were: a depression of the essential fatty acid level (linoleic and arachidonic) in both groups of patients together with a concomitant elevation of oleic acid in the bilharzial group and an elevation of oleic, palmitic, palmitoleic acids in the chronic active hepatitis group. The depression of linoleic and arachidonic acids was explained by the low fat diet intake, malnutrition, and the malabsorption factors which were frequent in all the patients studied. The elevation of monoethenoid acids was attributed to the decrease in the ability of the liver to desaturate the endogenous saturated and monounsaturated acids to polyunsaturated ones.

Effect of human plasma lipase on smooth muscle.

In the presence of serum albumin, the enzyme human plasma lipase produces a slow contraction of smooth muscle. This effect was not antagonized by antazoline or by atropine, and was completely abolished by heating the enzyme prepartion for 1 min at 60 degrees C. Calcium ions were found to potentiate the effect of plasma lipase on smooth muscle.

Effect of dextran gelatin on cholinesterase of rats.

This study has been carried out by measuring the cholinesterase (ChE) activity in blood serum and in some organs (brain, liver, spleen, kidney, small intestine, lung, and cardiac muscle) of rats before and at different time intervals after infusion of 65 dextran 70, and 5% gelatin 40 solutions (1 ml/100 g body weight). The controls received infusions of the diluent of the gelatin preparation. The data obtained showed that the infusion of the diluent in rats has no effect on ChE activity neither in blood serum nor in other organs at any time intervals after infusion. In case of dextran and gelatin, a significant increase in ChE activity in blood serum and the tested organs was observed at different time intervals after infusion. The increase in case of dextran was more marked than in case of gelatin. These measurements returned to base-line values during 72 h after infusion. Furthermore, the study failed to disclose any untoward reactions, either immediate or delayed, which could be attributed to the infusion solutions.

Biochemical changes induced in human plasma by its lipoprotein lipase.

1. Incubation of human citrated plasma with a concentrate of lipoprotein lipase (separated from the same plasma pool), for 6 hr at 37 degree C and pH 7.0, caused a marked decrease in the concentrations of calcium, triglycerides, total phosphorus, lipid phosphorus and total fatty acids. 2. There was a concomitant increase in the concentrations of non-esterified fatty acids and inorganic phosphorus which were presumably formed by enzymatic hydrolysis of triglycerides and lipid phosphorus. 3. These changes in human plasma, induced by its lipoprotein lipase, were quantitatively comparable to the same changes which have been previously reported in liquid plasma between the 1st and 2nd months of storage at room temperature.

Effect of gelatin infusion on urinary excretion of water and electrolytes in rats.

The effect of gelatin infusion on water and electrolyte excretion in urine was studied by measuring the volume of excreted urine and the urinary excretion of Na+, K+, Ca++ and Mg++ in a group of male rats before and after receiving infusions of a 5% autoclaved gelatin solution containing 1% glycine (1 ml/100 g body). A similar group of rats received the diluent only (control group). The results obtained showed that the diluent had a diuretic and natriuretic effect but with a less marked degree than gelatin solution which caused marked diuresis, natriuresis and increased excretion of Ca++ and Mg++ in the urine. The K+ excretion was significantly decreased following gelatin infusion. All of these measurements returned to the base-line level after 72 h following gelatin infusion.

Bood glucose level in pregnancy.

Oral glucose tolerance curves were constructed for 50 normal pregnant women, 25 pre-diabetics and 25 cases of diabetic pregnant women of different degrees of disturbance in carbohydrate metabolism. The mean rise in blood glucose level after the intake of 50 g glucose, was 53% in normal cases, and only 41% in the prediabetic cases, due to increased insulin secretion in the prediabetic group. This group of pregnants gave flat-topped curves in 60% of the cases studied, as compared to 10% of the normal pregnant cases in the same study. This was attributed to delayed insulin secretion in the prediabetic group. On the other hand, all diabetic cases gave peaked glucose tolerance curves during the first hour after glucose intake. The results of insulin-glucose tolerance test, effect of fasting for four hours and tolbutamide sensitivity test suggested that the prediabetic pregnants showed hyperinsulinemia which became evident during fasting. The pancreas of the prediabetic responds more readily, by the release of insulin, to the stimulus of oral hypoglycemic agents, such as sodium tolbutamide, than in the case of normal pregnants. Measurements of serum inorganic phosphorus, serum potassium and serum alkaline phosphatase of these 3 groups of pregnants, showed a definite disturbance in the liver function of the prediabetics which became more obvious in the diabetic group.

Effect of gelatin infusions on blood serum lipid pattern.

The effect of gelatin infusions in rat on the various serum lipid constituents was studied by measuring the mean values of total lipids, lipoprotein lipase, triglycerides, phospholipids, cholesterol, non-esterified fatty acids, and lipoproteins. These measurements were made immediately following a single intravenous infusion of gelatin solution (1 ml/100 g body wt) and at different time intervals post-infusion. Repeated intravenous infusions of gelatin were also given to another group of rats and the above mentioned lipid constituents were measured 24 h after each dose. The results obtained showed that gelatin infusions have a definite hypolipemic effect. There was a significant reduction in the levels of total lipids, triglycerides, cholesterol, and B + preB/alpha ratios immediately following infusion and at 5, 24 and 48 h postinfusion. This reduction was transient and the values were gradually normalized at the end of the first week postinfusion. In rats receiving repeated i.v. infusions, the results obtained showed a significant decrease in the same lipid constituents during the whole month of gelatin administration. Values of lipoprotein lipase, lipid phosphorous and non-esterified fatty acids showed insignificant changes from baseline values at all time intervals following single and repeated i.v. infusions of gelatin solution.

Evaluation studies on oxypolygelatin and degraded gelatin as plasma volume expanders.

Oxypolygelatin (CAS 9005-91-8, OPG) and degraded gelatin (CAS 9000-70-8, DG) have attracted the interest of many investigators as promising plasma protein substitutes. This paper deals with comparative evaluation studies on OPG and DG as regards stability and some biochemical consequences following i.v. infusions in rabbits. Accelerated aging tests showed a decrease in pH of OPG from 7.3 to 7.0. The pH of DG increased from 5.2 to 5.4 during the same period of aging. In both cases, the buffer capacity increased 3.0 to 3.5 in case of OPG and from 2.5 to 3.7 in case of DG. The relative viscosity of OPG decreased from 2.18 to 1.98 as compared to 1.79 to 1.58 in case of DG. Comparative studies on both OPG and DG postinfusion in rabbits, showed significant (p < 0.001) retention OPG in blood 24 h postinfusion, at which time, DG was practically absent. The decline in rabbit plasma protein was marked and more persistent in case of compared to DG. Plasma sodium showed a significant decline (p < 0.05) in case of OPG 1 h postinfusion, while plasma potassium showed a significant decline (p < 0.05) immediately postinfusion. In case of OPG, serum calcium showed a significant decline (p < 0.001) immediately postinfusion. This effect was marked at 1 h, 5 h and 24 h postinfusion. In case of DG, no significant changes in the levels of sodium, potassium, calcium and magnesium were observed at all time intervals postinfusion of the plasma volume expander.

The fate of intravenously infused gelatin.

The fate of i.v. infused gelatin was studied by measuring the rise in the level of total hydroxyproline (HP) in some organs of the rat following the infusion of a 5% autoclaved gelatin solution (1 ml/100 g body weight). The results obtained showed that HP levels were consequently increased in all of the organs studied, then the levels were generally normalised during the 3rd day post infusion. Small concentrations of HP were still retained by the kidneys and blood plasma, at the end of the first week after infusion. The rat ratio HP/creatinine (HP/C index), which increased from 0.33 to 3.78 during the first 24 h post infusion, declined gradually to the base-line level after 4 weeks, during which time 94% of the HP infused could be accounted for in the urine. Most of the HP was excreted in the bound form.