Cytochemical Study of Interstitial Cells in the Bat Ovary

Abstract

THERE are several types of glandular tissue in the mammalian ovaries and in the adjacent mesovaria, which are generally described as interstitial gland cells¹. The different views regarding their origin have been reduced by Brambell¹ to two comprehensive theses, namely epithelial origin and the connective tissue origin of the interstitial cells. No work has been done to compare or to contrast the cytochemical nature of these different types of cells in the ovary of the same mammal. Most of the cytochemical work has been carried out on the interstitial cells of thecal or connective tissue origin in the ovaries of a variety of mammalian species^2–7. The ovaries of non-pregnant and pregnant grey bats (Myotis grisescens) show two types of interstitial cells^3,8. The first type of cells are considerably developed and occupy all the ovary except the periphery which contains small follicles; they originated by the thecal hypertrophy of atretic large preantral and antral follicles and they are apparently developed to the same extent in the ovaries of pregnant and non-pregnant bats³. Mossman et al.⁹ have recently designated these cells of thecal origin as the interstitial gland cells in the mammalian ovary. The second type of interstitial cells in the bat ovary are in the form of cords of small epithelial cells, which are irregularly distributed among the first type of interstitial cells. The present investigation was undertaken to determine the nature of both types of interstitial cells by comparing and contrasting their cytochemical changes in the ovaries of non-pregnant and pregnant bats (Myotis grisescens) which were collected from January to June in the U.S.A. The fixing fluids and cytochemical techniques previously reported were also used in this investigation.