Choline acetyltransferase activity parallels the pressure gradient in the feline pharyngo-esophageal region

Pressure generated by the pharyngeal constrictor muscles and proximal esoph agus involve acetylcholine-induced muscle contractions. We hypothesized tha t the pharyngo-esophageal pressure gradient is related to choline acetyltra nsferase activity. In nine anesthetized cats, hypopharyngeal pressure and p roximal esophageal pressure were recorded with a solid state transducer ass embly. Enzymatic activities in the thyropharyngeus, cricopharyngeus, and pr oximal esophageal muscles were measured. Hypopharyngeal pressure was higher than the proximal esophagus (p < 0.01), and choline acetyltransferase acti vity was higher in the cricopharyngeus compared to the proximal esophagus ( p < 0.05). The pressure gradient between the hypopharynx and proximal esoph agus may be influenced by the activity of choline acetyltransferase. (C) 20 01 Elsevier Science B.V. All rights reserved.