Light and electron microscopy of the ovarian interstitial tissue in the senile rat: normal aspect and response to HCG of "deficiency cells' and 'epithelial cords'.

The two components of the interstitial tissue in the senile rat's ovary--deficiency cells and epithelial cellular cords--both contain steroidogenic organelles at a very low level of activity, which can be notably raised by HCG. Deficiency cells and epithelial cords are not the expression of primary ovarian aging, but the consequence of senile gonadotropic hypofunctioning. For that same reason, these ovarian structures become permanent and their possible cellular aging can thus be studied. No ultrastructural signs of senescence have as yet been observed.