A histological study on the coronary artery of the indigenous black Bengal goat in Bangladesh.

The coronary artery of the black Bengal goat was studied by light microscopy. The wall of the coronary artery consisted of the tunica intima, tunica media and tunica externa. The tunica intima consisted of a single layer of flattened endothelium. The tunica media was well-developed and composed of mainly of smooth muscle cells together with some fine elastic fibers. The tunica externa consisted of predominant collagen fibers, and some elastic fibers and smooth muscle cells. Elastic fibers in the tunica externa formed a circular arrangement around the tunica media. Sex differences were not observed. The media with well-developed smooth muscle cells may be responsible for changes in functional physiological conditions of the heart.