Localization of-monoamine positive structures in the ovary and oviduct of developing rats

Abstract

The aim of this study was to investigate the localization and distribution of sympathetic positive structures in the female gonads and oviducts of 15 30 and 60-day-oldAO rats. Histofluorescence and immunohistochemistry methods were used to determine their distribution in the ovary and oviduct, as well as for identification of dopamine and serotonin within sympathetic positive structures. Total monoamine positive structures (fibers and cells) were mainly localized under the surface epithelium, between follicles, especially surrounding groups of primary follicles and between secondary interstitial cells. The distribution of dopamine (DA) immunolabelled fibers and cells was in accordance with the distribution of total monoaminergic structures detected using histofluorescence. However, the density of structures labeled with DA antibodies was lower compared to total catecholamine positive structures detected by the fluorescence method. Delicate serotonin (5-HT) positive fibers were present mainly under the surface epithelium and in interstitial tissue between the cortex and medulla. In the hilum and medulla 5-HT positive cells were found perivascularly, while a dense population of 5-HT positive cells was found in the oviduct and mesovarium in 60-day-old animals. No corpus luteum cells were labelled using either of the two methods. Our findings corroborate observations that the monoamine supply of the ovary is not exclusively via extrinsic innervation and that intragonadal sources have an important role in their synthesis. Furthermore, the intraovarian localization of these elements suggests that monoamines exert direct or indirect effects on ovarian function.