Effect of vitamin D deficiency on urinary excretion of connective tissue derivatives (hydroxyproline and glycosaminoglycans) in rats.

The urinary excretion of two connective tissue metabolites was studied in both control and vitamin D deficient rats. Hydroxyproline (HyPRO) excretion was determined after 2, 13 and 22 months (experiment I). It decreased with aging in animals receiving the control diet.

[Effects of soluble carbohydrates from several tropical foods (cassava, peanuts, coconut and papaya) on calcium utilization in the rat].

Ethanolic extracts containing soluble sugars were prepared from four foods : cassava, peanut, coconut and papaye. Six-month-old rats were given by stomach tube 10 mM CaCl2 solution (+ 45Ca) containing a carbohydrate. Depending on the group, the carbohydrate was glucose or melibiose or raffinose at 200 mM concentration, or one ethanolic extract.

[Relations between the phosphorylation of aminated molecules and their action on the absorption of calcium].

Various amino acids and guanidines (L-lysine, L-aspartic and L-glutamic acids, creatine, taurocyamine and glycocyamine), studied in ileal ligated loops, increased intestinal calcium absorption in the rat. L-arginine was effective per os. Since these compounds are highly phosphorylable, a phosphorylation mechanism may be involved in the stimulation of calcium absorption.

[Action of soluble carbohydrates from avocado (Persea gratissima Gaertner) fruit on utilization of calcium in the rat].

Ethanolic extract containing soluble sugars was prepared from avocados (variety americana) coming from Madagascar. In this extract, thin layer and paper chromatography showed the presence of a ketoheptose, the mannoheptulose, in amount of 0.1 g/ml extract or 1.

The relations between intestinal alkaline phosphatase and carbohydrates with regard to calcium absorption.

The effect of carbohydrates on calcium absorption were studied in situ following the injection of a solution containing CaCl2 (+45Ca) into the ileal loop. The increase in Ca absorption was proportional to the concentration of carbohydrates injected and could be attributed to a progressive increase in the duration of absorption. In the ileal loop, sorbitol was much more effective than L-arabinose at equal concentrations in activating absorption.

[Effect of sorbitol on the activity of alkaline phosphatases isolated from different areas of rat small intestine].

To elucidate by which way sorbitol (S) increases Ca absorption, the action of (S) on the alkaline phosphatases (A.P.) isolated from duodenum, jejunum and ileum of the young rat is studied.

[Effect of phosphate upon calcium intestinal absorption (author's transl)].

Adult rats receive 5 to 50 mM CaCl2 solutions in which glycerophosphate or sodium diacid phosphate may be added in variable quantity. These solutions are administered by gavage or in situ ligatured jejunal loop. The inhibition of calcium absorption dependent on simultaneously administered phosphate doses is well characterized: high for the lowest concentration, the inhibiting effect of phosphate doses decreases more and more reaching a limit from which phosphate supplementation has no effect.