Rat glomerulosa cells in primary culture and E. coli lipopolysaccharide action

Abstract

During endotoxic shock there is a dysfunction of the adrenal gland; both corticosterone and aldosterone secretion are altered. The aim of the present study is to use glomerulosa cells in primary culture as a target of lipopolysaccharide (LPS) action. Glomerulosa cells cultured in basal conditions are able to proliferate; bFGF and ACTH have antagonic effects, bFGF increases proliferation whereas ACTH is antimitogenic. LPS has a biphasic effect, in the short term it is antimitogenic and in the long term increases the proliferation rate. LPS inhibits ACTH-induced corticosterone secretion in a dose-dependent manner in glomerulosa cells in culture similar to that in fasciculata cells, but it does not exert an important direct effect on aldosterone secretion. These results show that LPS exerts different effects in ACTH and ANG II signal transduction pathways and in the two enzymes which catalyze the late step in the steroidogenesis, 11β-hydroxylase and aldosterone synthase, which could be in agreement with the existence of both enzymes, regulated independently, in rat zona glomerulosa cells.