PubMed Health⌕ Search

Biomedical subjects

J E Richey

Publications and source records attributed to J E Richey.

4 recordsLinked to original sources
PubMed1980

Fetal rat hepatic ultrastructural changes associated with organ culture and glucocorticoid treatment.

Fetal hepatic ultrastructure was examined from 18 days gestation to term. Such structure was compared to that of tissue obtained at 18 days gestation which had been maintained in organ culture for 24, 48, and 72 h. In addition, the effects of maternal glucocorticoid administration in vivo and in vitro organ culture glucocorticoid exposure upon fetal hepatic morphogenesis were examined. Enhanced fetal hepatocyte ultrastructural maturation, characterized by a reduction in hematopoietic percursors, an increased frequency of hepatocyte-hepatocyte contact, a complete compliment of intracellular organelles, and the development of bile canaliculi by either maternal in vivo or in vitro fetal organ culture glucocorticoid exposure, was demonstrated. These studies extend previous observations concerning bile salt synthesis and secretion by fetal hepatic tissue both in vivo and in vitro by providing an ultrastructural basis for the functional changes observed and reported to occur in response to steroid therapy

Animals↗
PubMed1979

Taurocholate pool size and distribution in the fetal rat.

Taurocholate concentrations in fetal and neonatal rats were determined by radioimmunoassay. Total body taurocholate pool size varied from 0.0049 +/- 0.0008 to 203 +/- 8 nmol/g body weight from day 5 of gestation to 5 d after birth. A 50-fold increase in taurocholate pool size was observed between days 15 and 19 of gestation. The distribution of taurocholate between liver, intestine, and the remainder of the carcass was determined for rats of gestational age 19 d to 5 d after birth. The major fraction of total body taurocholate was in the liver and intestine, with less than 15% in the remainder of the carcass. The ratio of taurocholate in intestine to taurocholate in liver, which was 1:17 at 19 d of gestation, had altered substantially to a ratio of 6:1 by 5 d after birth. Treatment of pregnant rats with 60 microgram/d of dexamethasone from gestational day 9 until sacrifice increased fetal taurocholate pool size by 80% at 15 d, 40% at 19 d, and 16% at 1 d after birth. Administration of dexamethasone to the mother also changed the ratio of taurocholate in intestine to taurocholate in liver. At 19 d of gestation, dexamethasone-treated mothers had fetuses with approximately equal amounts of taurocholate in intestine and liver. This suggested that adrenocorticosteroids stimulate the early maturation of factors controlling taurocholate pool size and tissue distribution in the rat fetus.

Animals↗