HCS-HCG regulation in cultured placenta.

Tissue culture has been used to study the action of different substrates on the secretion of HCG and HCS in human placental explants. The following compounds have been studied: prostaglandins E2 and F2alpha, adrenaline and noradrenaline, oestriol and progesterone, glucose concentration. The investigators first measured the normal secretion of three term placentas and 2 months placentas. The activity of the compounds tested is expressed in per cent of the normal values. The investigators have checked that the cultivated cells were always viable by measuring the oxygen consumption during all the experiments. PG E2 and F2alpha are without action on term placentas. Adrenaline and noradrenaline reduce significantly the secretion HCS by full term placentas and have no action on HCG secretion. Oestriol always stimulates HCS secretion by full term placentas and 2 months 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 by placentas but high values of glucose in the medium signficantly reduce the HCS secretion by full term placentas.