Comparative Histology, Histometry and Histochemistry of the Right Coronary Artery in Sheep and Goats
Lakshmi Likitha.B
Department of Veterinary Anatomy, College of Veterinary Science, P.V.N.R. Telangana Veterinary University, Rajendranagar, Hyderabad- 500 030, India.
Senthamil Selvan P *
Department of Veterinary Anatomy and Histology, RIVER, Kurumbapet, Puducherry, 605 009, India.
Purushotham.G
College of Veterinary Science, Mamnoor, Warangal Dist-506 115, India.
Pramod Kumar.D
College of Veterinary Science, Rajendranagar, Hyderabad- 500 030, India.
Lakshman.M
Department of Veterinary Pathology, College of Veterinary Science, Rajendranagar, Hyderabad- 500 030, India.
*Author to whom correspondence should be addressed.
Abstract
Diseases of the Right coronary artery (RCA) cause ischemia of the right ventricle, ventricular dysfunction and severe cardiac failure. Sheep and goats are among the preferred animal species in cardiovascular research. Histological and histochemical assessment of the coronary artery in health and disease are critical to evaluate disease progression in these animal models. This study aims to report in detail on the comparative histological, histometrical and histochemical features of RCA in sheep and goats to assess suitability. We found that RCA was a muscular artery in both species and consisted of all three tunics, i.e tunica intima, tunica media and tunica externa. The subendothelial tissue was thinner and was completely absent at the arterial termination in goats. The tunica media was formed of multiple layers of smooth muscle cells but was comparatively thinner in goats. Tunica adventicia was rich in elastic fibres in both species. Histometric observations revealed significant variations between species in parameters such as, mean wall thickness, its tunics and luminal diameter. Histochemical reactions for mucopolysaccharides, acid phosphatase enzyme, alkaline phosphatase enzyme revealed positive reactions at varying levels in the tunics of the RCA in these animals. The reaction for fat with Oil red O was negative in both species.
Keywords: Right coronary artery, histology, histometry, histochemistry, acid phosphatase, alkaline phosphatase, mucopolysaccharides, fats