HCS-HCG REGULATION IN CULTURED PLACENTA

Tissue culture was used to study the action of different substrates on the secretion of HCG and HCS in human placental explants. The following compounds were studied: prostaglandins E2 and F2α, adrenaline and noradrenaline, estriol and progesterone, glucose concentration. The investigators first measured the normal secretion of 3 term placentas and 2 mth placentas. The activity of the compounds tested is expressed in percent of the normal values. The investigators checked that the cultivated cells were always viable by measuring the oxygen consumption during all the experiments. PG E2 and F2α are without action on term placentas. Adrenaline and noradrenaline significantly reduce the secretion of HCS in full term placentas and have no action on HCG secretion. Estriol always stimulates HCS secretion in full term placentas and 2 mth old placentas, whereas progesterone stimulates young placentas and inhibits full term placentas. Both steroids have no action on HCG secretion. Glucose is essential for HCS secretion in placentas but high values of glucose in the medium significantly reduce the HCS secretion in full term placentas.