Functional morphology of arteriovenous anastomoses on rat ovary

Abstract

This study aims to show the morphology of the structure involved in the function of arteriovenous anastomoses (AVA) under electron microscope. The study used 20 adult females of Rattus norvegicus. Ovarian tissue samples were fixed in 3% Glutaraldehyde in phosphate buffer, and then post–fixed in increasing concentrations of Ethanol, tissues were embedded in Epon resin. Semi–thin tissue sections were double stained with Uranyl acetate saturated in 70% Ethanol and lead Citrate. The ultrathin sections were examined in a JEOL 100 C electron microscope. In the opened AVA section, tunica intima, tunica media, and adventitia layers were observed in the vessel wall structure. The endothelial cell was present in the tunica intima, and the lumen was open. Thick layered smooth muscle cells were found in the tunica media. The muscles were arranged inner longitudinally and outer circularly. The internal elastic membrane lies between the circular and longitudinal smooth muscle. In another section taken from the tunica adventitia, fibroblasts were observed between dense elastic and collagen fibrils. The longitudinal smooth muscle was contracted in the closed AVA section, and the lumen appeared in the typical asterisks shape. This study showed the functional morphology of the AVA's and detailed vessel wall structures in the rat ovary. Lumen structure with open and closed AVAs is also shown. With observations from this study, the functional properties of the formations in the AVA wall structure are explained in the rat ovary.