OVARIAN TRANSFORMING GROWTH FACTOR-α GENE EXPRESSION: IMMUNOHISTOCHEMICAL LOCALIZATION TO THE THECAINTERSTITIAL CELLS

Abstract

Rat ovaries were examined for the presence of transforming growth factor-alpha (TGF-α). Immature diethylstilbestrol-primed rats were treated for 3 days prior to sacrifice with or without FSH. Their ovaries were either fixed in formaldehyde for immunohistochemistry or the RNA was extracted for northern blot analysis. Hybridization with a rat TCF-d cDNA probe revealed a 4.5 kilobase mRNA whose abundance was markedly stimulated in the rats treated with FSH. Immunohistochemical staining, using a sequence specific monoclonal antibody to TGF-α, MF9, detected immunoreactive TGF-α only in the interstitial and theca cells. FSH treatment resulted in no appreciable change in the immunostaining. These results suggest that TGF-α is synthesized in the ovary, perhaps in the theca-interstitia1 compartment.