The effect ofl-thyroxine on the absorption of calcium and strontium

Résumé Chez le rat, l'administration del-thyroxine pendant les 3 jours précédant un dosage oral de⁴⁷Ca et⁸⁵Sr provoque une augmentation frappante de l'absorption des isotopes. On suggère que cette augmentation est le résultat de l'inhibition du bloc métabolique au passage du calcium et du strontium à travers l'intestin grêle par non assemblage de la phosphorylation oxydative par la thyroxine.     

The effect of lactose and iron on strontium absorption

In rats fed on a milk diet with or without the addition of lactose and/or iron the transileal strontium-85 transfer was higher by 14-38% and the intestinal strontium retention lower by 6-23% than in control rats fed on standard laboratory food.     

The effect of lactose and iron on strontium absorption

Summary In rats fed on a milk diet with or without the addition of lactose and/or iron the transileal strontium-85 transfer was higher by 14–38% and the intestinal strontium retention lower by 6–23% than in control rats fed on standard laboratory food.Presented, in part, at the 12th Yugoslav Symposium for Radiation Protection, Ohrid 1983, and at the 11th Regional Congress of IRPA (Austrian — Hungarian — Yugoslav Radiation Protection Meeting), Wien 1983. Acknowledgments. This work was supported by a research grant from the Scientific Research Council of the Socialist Republic of Croatia. The author thanks Mrs M. Buben for her technical assistance.     

The inter-relationships between calcium absorption and bile

Zusammenfassung Es wird eine positive Korrelation der Kalziumabsorption in Küken bei steigender Gallenmenge gefunden. Gemischte Mizellen der Galle aus Gallensäuren und Lecithin waren am wirkungsvollsten.     

The effect of fluorocitrate on urinary calcium and citrate excretion

Summary The renal handling of calcium and citrate was studied in dogs after the administration of fluorocitrate. The drug produced a significant increase in urinary calcium and citrate excretion. Net renal secretion of citrate occurred during the infusion of fluorocitrate since citrate clearances exceeded the glomerular filtration rate.     

Effects of stable calcium and strontium on deposition of calcium-45 and strontium-89 in bone

Zusammenfassung Nach einmaliger intraperitonealer Verabreichung von stabilem Kalzium oder Strontium in Mengen bis zu 3000 µg/g Körpergewicht war der Bruchteil des gleichzeitig verabreichten Ca⁴⁵, das sich im Rattenschenkel ablagerte, unverändert. Unter denselben Umständen verabreicht, verminderte stabiles Strontium im Schenkel abgelagertes Sr⁸⁹ ein wenig, aber stabiles Kalzium hatte keine solche Wirkung auf Sr⁸⁹.Während sich die Konzentration des Radioisotops nach einmaliger peroraler Verabreichung im entsprechenden Verhältnis zur Dosis des stabilen Kalzium- oder Strontiumgehalts vermehrte, waren im allgemeinen die Konzentrationen im Schenkel nach einmaliger peroraler Verabreichung kleiner als nach intraperitonealer Verabreichung.     

The effect of pyrophosphate and diphosphonates on calcium transport in red cells.

The effect of 0.5 mM pyrophosphate (PPi), disodium ethane-4-hydroxy-1,1-diphosphonate (EHDP) and disodium dichloromethane diphosphonate (Cl2MDP) on the ATP-dependent Ca2+ extrusion from the human red cell ghosts was studied. PPi and Cl2MDP had no effect, when introduced into the cells or added outside to the medium. EHDP slightly increased the calcium concentration in the released cells and slightly decreased the rate constant of the calcium transport, having opposite effects when it was inside or outside the cells. PPi and the 2 diphosphonates were not found to move easily across the red cell membrane.     

The role of calcium in the negative inotropic effect of lanthanum

Summary Lanthanum reduces the rate of calcium fast exchanging processes, whereas the slowly exchanging phase is not modified. Experimental data also confirm the importance of calcium fast exchanging fraction in regulating contractile force of cardiac muscle.     

The effect of dietary lactose on the ileal absorption of sodium taurocholate in rats]

When Rats were fed a lactose containing diet, both the absorption rate of sodium taurocholate at the level of ileum and the contents of bile acids of the small intestine were increased. On the contrary, feeding of lactose did not modify the daily fecal excretion of bile acids. It therefore appears that dietary lactose increases the intestinal pool of bile acids by increasing their ileal absorption rate and that this effect of lactose is not subordinated to a modification of bile acid synthesis.     

The effect of activated dimethicone,other antacid constituents,and kaolin on the absorption of propranolol

Summary A study was made of the effect of 6 commonly used gastrointestinal preparations on the absorption of propranolol using an in vitro experimental model. The constituents examined were activated dimethicone, aluminium hydroxide gel, bismuth carbonate, kaolin, magnesium carbonate, and magnesium trisilicate. A slight decreased propranolol absorption was given by kaolin (−13.0%), the other components showed smaller effects ranging from −6.8% to +6.6%. None of the results were statistically significantly different from control absorption values. Acknowledgment. We are grateful to I.C.I. Ltd, Macclesfield, England, for the gift of propranolol hydrochloride and to Galen Ltd, Craigavon, Northern Ireland, for the gift of dimethicone.     

The effect of calcitonin on calcium uptake in mouse molars in vitro

Summary Mouse maxillary second molars were removed at either 24 or 96 h of age and maintained in vitro. Half of the teeth, of each age group, were treated with 50 m-units of synthetic salmon calcitonin. By comparing the initial and final calcium concentrations in the medium, the net uptake or release of calcium was inferred. The treated molars took up significantly more calcium than the untreated groups.