Histochemical studies on the angioarchitecture of coronary artery in goat (Capra hircus)

Abstract

The present study was conducted on the coronary artery of 18 goats divided into three age groups viz., kid (up to 1 year), young (1-2 years) and adult (2 years and above) comprising of six animals in each group for recording the histchemical peculiarities. The histochemical study revealed that the PAS activity was limited to the tunica externa and intima of the coronary artery. Moderate PAS activity was recorded in the left coronary artery at the termination in all the age groups of goats, while at the origin of the right coronary artery very weak PAS activity was found. The deposition of lipids was found in all the tunics of the coronary artery. The amount of deposition of lipids in the tunica intima of left coronary artery was more than that deposited in the right one in all the age groups of goat and the deposition increased with the advancement of the age of the animals. The acid phosphatase activity was exhibited only in the endothelium and tunica externa of the coronary artery, whereas the alkaline phosphatase activity was noted in the endothelium, externa and perivascular connective tissues of the vessels. In adults, intense acid phosphatase activity was recorded in the tunica externa of left coronary artery with the endothelium showing very weak activity, while moderate activity was noted in the tunica externa of right coronary artery without any activity in the endothelium of this vessel in the adult animals. The present study shall be of value to clinicians for assessment of vascular configuration in health and diseases of coronary artery as well to study the haemodynamics in terms of lining endothelium and its modification for clotting mechanism.

Histological and ultrastructural studies on the coronary artery of adult domestic dog (Canis familiaris)

“…Microscopically, our work revealed that the dog's coronary artery showed the histological features of the medium‐sized muscular artery as it was composed of three tunics arranged from inward to outward as tunica intima, tunica media and tunica adventitia. These findings agree with several authors like Waller et al () in human, Bacha and Bacha () in domestic animals, Awal, Asaduzzaman, Prodhan, and Kurohmaru () in black Bengal goat, Khan, Khan, and Faruqi () in mammals, Eurell and Frappier () in domestic animals, Sathapathy et al () in goat and Likitha () in goat and sheep.…”

“…Our work indicated that the endothelial cells might be elongated and projected into the lumen in some arterial regions. Similar results were obtained in goat by Sathapathy et al () who explained that these endothelial cells act as endothelial cushions which regulate the blood flow, especially at the branching sites.…”

“…In this study, the tunica intima of the dog's left coronary artery was composed of two layers: lining endothelium and internal elastic lamina. This result is similar to black Bengal goat (Awal et al, ) and is partially similar to other mammals as human (Waller et al, ), goat (Sathapathy et al, ) and goat and sheep (Likitha, ) in which their tunica intima comprises three layers: endothelium, subendothelial connective tissue layer and internal elastic lamina.…”

“…According to Padmasri, Kumar, Purushotham and Raghavender, (), Khan et al () and Ross and Pawlina (), all the constituents of the tunica intima are observed to be undulated in cross section, which is due to the contraction of the smooth muscle fibres during artery processing (Sathapathy et al, ). This is in line with our result that revealed the wavy scalloped appearance of the internal elastic lamina.…”

“…They are situated on the heart epicardial surface (Burris & Shoukfeh, ). They are effective in autoregulation to maintain the coronary blood flow at levels suitable for cardiac tissue requirements (Sathapathy et al, ).…”