Short-term and long-term effects of unilateral external carotid artery ligation on orofacial functions in rats

This study was performed to investigate the effects of ECA ligation (ECAL) on immediate and long-term changes in masticatory and swallowing functions as well as the jaw-opening reflex evoked in the digastric muscle. The experiments were carried out using male Sprague-Dawley rats. In the acute experiment, the digastric reflex evoked by low-threshold electrical stimulation of the inferior alveolar nerve and the swallow reflex, identified by digastric and thyrohyoid electromyographic (EMG) bursts, were compared between before and 1 hour after ECAL. The chronic experiment was conducted on freely moving rats. EMGs of the masseter, digastric, and thyrohyoid muscles were chronically recorded. The long-term effects of ECAL on behavior and muscle histology were compared between rats with an intact ECA and rats with ECAL. In the acute experiment, the peak amplitude of the digastric reflex on the ECAL side was significantly decreased 1 hour after ECAL. In the chronic experiment, although most parameters of the masticatory and swallowing EMGs were not significantly different between the groups, the results suggest wide variation of the effect of ECAL on the muscles. Blood supply compensation from collaterals of the internal carotid artery may be permanent in some animals.PMID:38226423 | DOI:10.1152/ajpgi.00226.2023
Source: Am J Physiol Gastroi... - Category: Gastroenterology Authors: Source Type: research