The effect of 1alpha-hydroxyvitamin D3 and cortisone on the development of chick duodenal alkaline phosphatase in organ culture.

The development of alkaline phosphatase influenced by 1 alpha-OH-D3 (a synthetic active form of vitamin D3) and cortisone was studied in chick duodenal organ cultures. The administration of cortisone to the embryo in ovo on the 14th day of incubation resulted in a precocious increase in alkaline phosphatase after six days (20-day embryo). When duodena from 14-, 18- and 20-day embryos were cultured in the presence of cortisone, there was no significant enhancement of alkaline phosphatase activity except for a marginal effect observed in the 18-day duodenum.

Vitamin A transport in chicken plasma: isolation and characterization of retinol-binding protein (RBP), prealbumin (PA), and RBP--PA complex.

Vitamin A-transporting protein in chicken plasma was purified by column chromatography on DEAE-Sephadex and Sephadex G-100; the protein formed a complex of retinol-binding protein (RBP) with prealbumin (PA). The molecular weight of the 1:1 molar complex was estimated to be 76,000 by gel filtration, and the sedimentation coefficient (S20,W) was found to be 5.2 S.

Demonstration of two different vitamin D-dependent calcium-binding proteins in rat intestinal mucosa.

The characteristics and location of rat intestinal proteins with calcium binding properties were reexamined using both a 45Ca-equilibrated Sephadex G-100 column and the chelex 100 method in the assay of 45Ca binding activity. The rat intestinal mucosa was found to have three different proteins with calcium binding properties. Two of these proteins were found to be vitamin D-dependent and were examined in detail.

Effect of exogenous polyunsaturated fatty acids on lipogenic enzyme activity in rat liver under fixed carbohydrate consumption.

Studies were conducted to evaluate specific dampening of hyperlipogenesis (i.e. enhanced lipogenic enzyme activity of the liver in rats refed a high carbohydrate, fat-free diet: F-diet) by exogenous polyunsaturated fatty acids under fixed carbohydrate consumption.

The effects of maltitol on rat intestinal disaccharidases.

1. The highese disaccharidase activity for sucrose maltose and maltitol was found in the jejunum, followed by the ileum and duodenum. However, the disaccharidase activity for maltitol was extremely low compared with that for sucrose and maltose.

Binding of 7-dehydrocholesterol to sterol carrier protein and vitamin D3 effect.

It was confirmed that delta 5,7-sterol delta 7-reductase activity was suppressed by cholecalciferol (vitamin D3) in the enzyme system consisted of microsomes and sterol carrier protein (SCP). The enzyme activity was significantly decreased in the combination with microsomes obtained from either vitamin D-deficient or vitamin D3-treated rat liver and with SCP obtained from vitamin D3-treated rat. It was also demonstrated by the binding assay of the dextran-charcoal technique that 7-dehydrocholesterol binding to SCP could be specifically displaced by vitamin D3.