S-100 protein-immunoreactive cells in the bovine ovary.

The present study deals with an immunohistochemical localization of S-100 protein in the bovine ovary. Immunoreactivity for S-100 was observed in various types of cells, as well as in cells of the nervous system. The endothelial cells of arterial vessels, blood capillaries, and lymph vessels; the epithelial cells of ovarian cysts; and the oocytes of normal and atretic follicles showed an S-100 protein positivity. The immunoreactivity also was found in the epithelial cells of the rete ovarii. No cells other than these showed immunoreactivity to the anti-S-100 serum. S-100 protein can be a useful marker for providing information on ovarian function.