Micromorphology, Morphometry and Histochemistry of Left Coronary Artery in Sheep and Goats

Abstract

Coronary artery disease is the most common type of cardiovascular disease. Research in coronary artery disease often involves experimental animal models to identify the underlying mechanisms, test procedures, devices etc., and to practice best possible therapeutic interventions. Sheep and goat has evolved as experimental animals and studies on coronary artery disease are in progress in this animal models. This study on the left coronary artery (LCA) in sheep and goat is to report on its histological, histometrical and histochemical details and to assess the similarities and differences for translational significance. The LCA was a small and muscular type of artery in both species and consisted of all the three tunics, ie., inner tunica intima, middle tunica media and outer tunica externa. The histomorphology of the tunics in both the species were similar. Histometric measurements differed between them. The tunica intima and externa were significantly thicker with a significantly higher total wall thickness in goats. In sheep, the tunica media was significantly thicker than the goat. The endothelium of LCA in both the species was positive for acid mucopolysaccharides while the activity for neutral polysaccharides differed. Acid and alkaline phosphatase activity differed in the tunics of LCA in both sheep and goat. Lipid was not found in any of the tunics of LCA in both the species.