Collateral circulation in the rabbit tongue after common carotid ligation

A study was undertaken to ascertain the microvascular pattern of the collateral circulation of the tongue after unilateral ligation of the common carotid artery. The right common carotid artery was ligated in 25 New Zealand White male rabbits. These animals were killed in groups of five at intervals of an hour, six hours, 24 hours, one week, and two weeks. The vasculature in the head and neck of these animals was flushed with heparinized saline solution and perfused with latex. The results show that circulation was present but signifincatly reduced in the one-hour group, slightly reduced in the six-hour and 24-hour groups, and normal in the one- and two-week groups. This study indicates that the collateral circulation of the tongue is extensive and that a normal vascular pattern returns within a week after unilateral ligation of the common carotid artery.