Expression and Subcellular Localization of Endocannabinoid System in Primary Interstitial Glandular Cells In Situ of Mice Ovary

Endocannabinoid synthesizing 2-AG and cannabinoid receptors have been reported in some organ of reproductive system and in oocyte of ovary, but little is known about the expression and subcellular localization of CB1 and DAGL-α in interstitial gland tissue of mouse ovary. The aim of this study was to explain the differential distribution of endocannabinoid system in interstitial glandular cell of mouse ovary. The CB1 and DAGL-α-immunoreactivities were detected within cells, which are consisted of smaller mitochondria with non-tubular cristae and fewer lipid droplets within the interstitial glands. Their immunoreactivities were localized in association with small vesicle clustering dispersed throughout the cytoplasm. The identity of the immunoreactive cells within interstitial glands were showed a possibility of co-existence of CB1 and DAGL-α in steroidogenic cells and autocrine or paracrine exertion of eCB signaling as well as involvement of eCB signaling in regulation of cell differentiation were discussed. HIGHLIGHTS 2-arachidonoyl glycerol (2-AG, endocannabinoid)-synthesizing enzyme (DAGL-α) and its receptor CB1 localize to primary interstitial glandular cells of mice The first time of study for DAGL isozymes a co-localize with CB1 in interstitial glandular cells by Immuno-DAB-electron-microscopy. The new knowledge represents DAGL isozymes a and CB1 locate in the intracellular vesicles. This suggests that 2-AG by DAGL-α and CB1 receptor had co-existence its function through paracrine/autocrine released, as already known in oocyte, neurons and some other cells The distribution of DAGL isozymes a and CB1 in the interstitial gland tissues suggests that eCBs signaling molecules may be plays unique functions in steroidogenesis GRAPHICAL