EXPRESSION AND CELLULAR-DISTRIBUTION OF CYTOSOLIC PHOSPHOLIPASE A(2) IN THE RAT OVARY

Cellular expression of cytosolic phospholipase A(2) (cPLA(2)) was inve stigated in the rat ovary in different endocrine states. Its mRNA expr ession was detected by RT-PCR. The immunohistochemistry identified an intense signal for cPLA(2) in oocytes. Granulosa and thecal cells in g rowing follicles were negative, but turned positive during the periovu latory period, whereas those in atretic follicles were highly immunore active. The immunoreactive signal was modest in newly formed corpora l utea (CL) but intensified in functionally and morphologically regressi ng CL. These results show a broad but specific distribution of cPLA(2) in ovarian cell types, and suggest its role in ovulation, CL regulati on and apoptotic processes.