Interstitial cells of the ovaries of the chick embryo: ultrastructural aspects of their innervation.

In a previous work we demonstrated that germ and epithelial cells of the atrophic right ovary and of the medulla in the left functioning ovary undergo regression while interstitial cells are preserved. The objective of the present study was to analyze the relationship between nerve fibers and nerve endings and interstitial cells from both ovaries during embryogenesis in the chick. To this purpose, left and right ovaries from embryos of 7 to 19 days of development were processed for ultrastructural study and ultracytochemical determination of acid phosphatase. At 7 days, isolated interstitial cells were found in the central region of both ovaries, containing SER, Golgi apparatus, mitochondria with tubular cristae and abundant lipidic vacuoles. Nerve fibers and nerve endings were scarce. From the 11th day, interstitial cells were found grouped in the right ovary and in the medulla of the left one, and were related to nerve bundles surrounded by Schwann cells. The nerve ending, in close contact with the membrane of interstitial cells, contained mitochondria, microtubules and small and big vesicles, some with an electro-dense content. This relationship between interstitial cells and nerve endings and fibers was more frequent from the 15th day. The activity of acid phosphatase localized in germ and epithelial cells presented a more intense reaction in the right ovary and in the medulla of the left ovary at 15 days.(ABSTRACT TRUNCATED AT 250 WORDS)