Interstitial cells of Myotis myotis ovary during gestation. An ultrastructural study.

The purpose of this paper was to describe the ultrastructure of the interstitial cells of the bat ovary (Myotis myotis) during gestation (May and June). The Myotis myotis ovary has great amounts of interstitial tissue comprising of polyhedral elements with abundant cytoplasm filled with lipid droplets. Large mitochondria with an unusual parallel arrangement of the tubular cristae were observed. They consisted in four or five piled tubular elements. Numerous concentrically disposed agranular membranes were observed. The occupied large cytoplasm areas around some lipid droplets. These three strictly associated cellular components are interpreted as the expression of the steroidogenic activity of the interstitial cells.