Inverse Association Between Basilar Artery Volume and Neuron Density in the Stellate Ganglion Following Bilateral Common Carotid Artery Ligation: An Experimental Study.

Abstract

OBJECTIVE: This study examined the relationship between neuron density in the stellate ganglion and the severity of basilar artery (BA) enlargement after bilateral common carotid artery ligation. METHODS: Rabbits (n = 24) were randomly divided into 3 groups: unoperated control group (n = 4), experimental group subjected to bilateral common carotid artery ligation (n = 15), and sham-operated control group (n = 5). Histologic examination of the BAs and stellate ganglia was performed 2 months later. Permanent bilateral common carotid artery ligation was induced by ligation of common carotid arteries at prebifurcation levels as a model for steno-occlusive carotid artery disease. RESULTS: Mean BA volume and neuron density in stellate ganglia for all animals were 4200 μm± 240 and 8325 μm± 210. In sham-operated animals, the mean values were 4360 μm± 340 and 8250 mm± 250. For the experimental group, mean volume and density in animals with slight dilatation of the BA (n = 6) were 4948 μm± 680 and 10,321 mm± 120, whereas in animals with severe dilatation (n = 9), the values were 6728 μm± 440 and 6300 mm± 730. An inverse association was observed between degree of BA enlargement and stellate ganglia neuronal density. CONCLUSIONS: High neuron density in stellate ganglia may protect against steno-occlusive carotid artery disease by preventing BA dilatation and aneurysm formation in the posterior circulatory arteries.