A possible interrelationship between gonadotrophin stimulation and prostaglandin F2alpha inhibition of steroidogenesis by granulosa-luteal cells in vitro.

The newly formed corpus luteum of many species is refractory to the lytic action of prostaglandin F2alpha (PGF2alpha). This phenomenon was studied utilizing porcine, bovine and human granulosa-luteal cells in tissue culture. The steroidogenic potential of the granulosa-luteal cells was critical in determining whether PGF2alpha could inhibit progesterone production. Since the steroidogenic potential of the granulosa-luteal cell is related to the amount of LH bound to the cell, the bound LH may protect the granulosa-luteal cells from the lytic action of PGF2alpha. Finally, a 'see-saw' type of interaction between LH and PGF2alpha is postulated to account for the resistance of the newly formed corpus luteum to PGF2alpha.