Amino acid transport by small and large intestine of newborn pig

Summary Unidirectional fluxes of different amino acids have been determined across newborn pig small intestine and colon. The systems responsible for amino acid transport are present in the same proportion in both tissues. Colonic transport of amino acids appears to represent a transient overspill function of the small intestine.     

Autoradiographic demonstration of estrogen uptake by the armadillo pituitary gland

Summary Adult female armadillos were injected with tritiated estradiol. The pituitary gland was removed and processed for autoradiography. Nuclear uptake and retention of the steroid was found in 28.8% of the cells in the pars distalis and 3.7% of the pituicytes.This study was supported in part by USPHS Research Career Development Award NS 00164 (PJS) and USPHS Grants NS 12933, HD 10914, HD 10202, and RR 07187.     

The transport of various immune globulins by the new-born pig intestine

Resumen El intestino delgado del cerdo recién nacido, usado in vitro, transporta immunoglobulina G (IgG) de bovino más rápido que IgG de porcino. El transporte intestinal tanto de sodio como de fluido aumenta en presencia de IgG de bovino. Preparaciones de IgG de ovino, equino y humano son transportadas a igual velocidad que IgG de porcino. Estas proteínas no estimulan la transferencia de sodio o fluido. Esta diferencia en la velocidad de transporte entre IgG de bovino y porcino pone en duda la opinion general que sostiene que la absorción de proteína en el intestino de cerdo es enteramente no selectiva.     

Calcium dependence of protein transport by the small intestine of the new-born pig

Resumen El transporte de albumina en el intestino delgado del cerdo esta asociado con un aumento en el transporte de fluido. Ambos transportes son inhibidos por altas concentraciones de calcio. Ausencia de calcio tambien inhibe el transporte de albumina. Condiciones optimas en el transporte de albumina y fluido se obtienen usando Cl₂Ca4 mM en el medio. Se deducen analogias al comparar estos resultados con resultados similares en ameba, obtenidos de la literatura.     

5-Hydroxytryptamine: Autoradiographic evidence for uptake into fibroblast cell nuclei

Summary After incubation with tritiated 5-HT, activity is autoradiographically localized over fibroblast nuclei. This may indicate an effect of 5-HT directly on the nuclei of these cells.     

Starvation-induced changes in the autoradiographic localisation of valine uptake by rat small intestine

We report here the effects of a 72-h fast on the localisation of Na-dependent [3H]-valine uptake by rat small intestine. Starvation results in the earlier appearance of valine transport during cell migration and an enhanced accumulation of the amino acid at the villus tip.     

Starvation-induced changes in the autoradiographic localisation of valine uptake by rat small intestine

Summary We report here the effects of a 72-h fast on the localisation of Na-dependent [³H]-valine uptake by rat small intestine. Starvation results in the earlier appearance of valine transport during cell migration and an enhanced accumulation of the amino acid at the villus tip.Acknowledgments. We wish to thank MW Smith, PS James and IS King (AFRC Institute of Animal Physiology, Babraham, Cambridge) for facilities and advice regarding autoradiography. Financial support from the British Digestive Foundation and Eli Lilly and Company is appreciated.     

Autoradiographic analysis of FSH binding during follicular atresia

Binding of FSH to ovarian cells was studied in PMSG primed immature Swiss mice, 48 h after PMSG treatment, FSH-binding was higher in the periphery than in the cumulus cells of the antral follicles. Binding of FSH to granulosa cells of normal follicles was observed to be specific, 48 h after PMSG injection. No localization in the atretic follicles could be seen by autoradiography 72 h after priming.     

Autoradiographic localization of the uptake of 3H-beta-alanine in rat nervous tissue cultures.

Autoradiographic studies on the uptake of 3H-beta-alanine have shown that, in spinal cord and brain stem cultures, both neurones and glial cells have accumulated the amino acid. In contrast, in cultures of cerebellum and dorsal root ganglia, 3H-beta-alanine was only t aken up by glial elements.     

Autoradiographic demonstration of uptake and accumulation of3H-6-hydroxydopamine in adrenergic nerves

Zusammenfassung Die Regenbogenhaut der Maus wurde in einer physiologischen Pufferlösung mit radioaktivem 6-Hydroxydopamin (³H-6-OH-DA) inkubiert. Mit Hilfe autoradiographischer und fluoreszenz-histochemischer Untersuchungen konnte gezeigt werden, dass³H-6-OH-DA in die adrenergischen Nervenfasern der Regenbogenhaut aufgenommen und gespeichert wird. Dieser Befund bringt die direkte Erklärung der durch 6-Hydroxydopamin induzierten Degeneration der adrenergen Fasern.     

Villus growth and cell replacement in the small intestine of the neonatal pig

Summary Cells produced in the crypts of newborn pig ileum migrate onto villi during development. There is little or no corresponding loss of cells from villus tips during the first week of postnatal life. Villus growth during this period is largely responsible for the slow rate of cellular renewal seen to take place.     

Villus growth and cell replacement in the small intestine of the neonatal pig

Cells produced in the crypts of newborn pig ileum migrate onto villi during development. There is little or no corresponding loss of cells from villus tips during the first week of postnatal life. Villus growth during this period is largely responsible for the slow rate of cellular renewal seen to take place.     

Effect of chronic hypo and hypervitaminosis C on the brush border enzymes and the intestinal uptake of glucose and alanine

Summary Brush border sucrase and alkaline phosphatase activities are considerably enhanced in the intestine of ascorbic acid deficient guinea-pigs. Similar increase in the uptake of D-glucose and L-alanine also occurs in chronic vitamin C deficiency. However the permeability of D-glucose and L-alanine in the intestine of animals fed with large doses of vitamin C is severely depressed, with a reduction in the levels of sucrase and alkaline phosphatase activities.