RESUMO
Enzymic changes in primary cultures of granulosa cells over 9 days were measured and compared with changes occurring during follicular development in vivo. Characteristic of in vivo development of granulosa cells was a large increase in activities of the NADP+-dependent isocitrate, glucose-6-phosphate dehydrogenases and malic enzyme, and smaller increases in the activities of the NAD+-dependent lactate and malate dehydrogenases. In vitro, the NAD+-dependent dehydrogenases increased in activity, while the NADP+-dependent enzymes showed transient or no changes. Despite the uncharacteristic metabolism, granulosa cells in culture could synthesize steroids. Our results suggest that the cells in vitro and in vivo use different metabolic pathways to support syntheses dependent on reducing equivalents.
Assuntos
Células da Granulosa/fisiologia , Esteroides/biossíntese , Animais , Células Cultivadas , Feminino , Variação Genética , Glucosefosfato Desidrogenase/metabolismo , Células da Granulosa/enzimologia , Isocitrato Desidrogenase/metabolismo , L-Lactato Desidrogenase/metabolismo , Malato Desidrogenase/metabolismo , NAD/metabolismo , NADP/metabolismo , Progesterona/biossíntese , SuínosRESUMO
1. Milk productions and 7 d dietary records were determined on twenty-seven mothers who had been breast-feeding for 1, 3, 6, 9, 12 or 15 months. 2. The mean milk productions for each group of mothers was 1 . 87, 1 . 238, 0 . 884, 0 . 880 and 0 . 951 kg/24 h at 1, 3, 6, 9, 12 and 15 months of lactation respectively. There was no significant difference between two milk determination 3--7 d apart on each mother or between the mean milk production of each group of mothers. 3. Energy intakes of the infants was found to be higher than the usually-accepted values at 1 and 3 months of age but by 6 months were similar to the accepted normal values. 4. Energy intakes of the mothers although greater than those recommended for similar non-lactating women were not sufficient to take into account the energy content of the milk.
Assuntos
Aleitamento Materno , Lactação , Adulto , Austrália , Peso ao Nascer , Peso Corporal , Dieta , Metabolismo Energético , Feminino , Humanos , Lactente , Masculino , Gravidez , Fatores de TempoRESUMO
1. Adrenaline increased hepatic tyrosine aminotransferase activity when injected into foetal rats or 2-day-old rats. 2. The inhibition of the postnatal increase in tyrosine aminotransferase activity which occurred in adrenalectomized newborn rats rapidly overcome by injection of adrenaline or dibutyryl cyclic AMP. 3. The effects of adrenaline or dibutyryl cyclic AMP on the tyrosine aminotransferase activity in foetal, adrenalectomized newborn and 2-day-old rats could be partially or completely blocked by prior treatment with actinomycin D. 4. Dibutyryl cyclic AMP induced tyrosine aminotransferase activity in hepatocytes cultured from 15-day foetal rats in glucocorticoid-free medium. 5. Actinomycin D at 0.2 microgram/ml in the culture medium completely prevented the induction of tyrosine aminotransferase activity by dibutyryl cyclic AMP in cultured cells. 6. The results suggest that adrenaline and cyclic AMP stimulate a transcriptional event during induction of tyrosine aminotransferase in perinatal liver.
