Regulation of steroidogenesis in jc-410, a stable cell line of porcine granulosa origin

We investigated the regulation of steroidogenesis in a cell line of porcine granulosa origin, JC-410. Cells responded to the protein kinase-A activato rs, cholera toxin and forskolin, with increased accumulation of intracellul ar cAMP. Histochemically, cells were shown to contain 3 beta-HSD, the enzym e which converts pregnenolone to progesterone. The JC-410 cells produced pr ogesterone and responded to the protein kinase-A activators with an increas e in progesterone synthesis. Progesterone levels were also increased by 25- hydroxycholesterol, pregenolone, estradiol and androstenedione. Follicle-st imulating hormone and luteinizing hormone had no effect on cAMP or progeste rone accumulation. Androstenedione was required for the synthesis of estrad iol by JC-410 cells. Steady-state levels of mRNA for the steroidogenic enzy mes 3 beta-HSD and P450scc were increased by treatment with cholera toxin, whereas P450arom was not changed. These cells express the steroidogenic enz ymes genes in a similar fashion to primary cultures of porcine granulosa ce lls. The JC-410 cells may represent a valuable model to study second messen ger regulation and the molecular mechanisms involved in steroidogenesis in granulosa cells. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved .