Oxygen Uptake, Glucose Utilization, Lactate Release and Adenine Nucleotide Content of Sheep Ovarian Follicles in Culture: Effect of Human Chorionic Gonadotrophin

Abstract

A study has been made of the oxygen uptake, glucose utilization, lactate release and cellular content of adenine nucleotides of isolated sheep ovarian follicles (4-6 mm in diameter) maintained in organ culture, and of the effects on these parameters of the addition of human chorionic gonadotrophin (hCG). The mean oxygen consumption of the entire follicles when freshly isolated and of the theca and membrana components was 0·56, 1·08 and 0·05 .umol per milligram wet weight of tissue per hour respectively. About 8.umol of glucose was taken up and 16 .umol of lactate released per milligram wet weight of follicular tissue per hour during the first 24-h period of culture. This rate reduced by about 30 % for each subsequent day of culture, but was significantly increased by the addition of hCG. The mean ATP content of theca and granulosa tissues was 4·6 and 2·8 nmol/mg wet weight of tissue respectively. There was no discernable change in tissue adenine nucleotide content or energy charge ratio during the 3-day culture period, and prolonged exposure to hCG was without effect. Untreated follicles produced both oestrogen and androgens throughout the culture period. The addition of hCG resulted in a transitory stimulation in oestrogen secretion, inhibition of androgen secretion, and a marked and sustained rise in progestin secretion.