Ethanol-induced esophageal motor disorder: development of an animal model

Abnormal esophageal motility has been reported in alcoholics. This includes abnormally high esophageal contraction amplitudes (ECA) and elevated lower esophageal sphincter pressures (LESP). However, an animal model is lacking for evaluating the underlying mechanisms. To develop such a model of ethanol-induced esophageal motor dysfunction, esophageal manometry was done in control, chronically intoxicated, and withdrawing cats. Ethanol was administered for at least 30 days via gastrostomy tube and blood alcohol levels, typically 300 mg/dl, were adjusted to maintain inebriation. LESP and upper (striated muscle) and lower (smooth muscle) ECA were elevated in male withdrawing cats. In intoxicated cats only upper ECA was elevated. Surprisingly, LESP and ECA were not significantly affected in females. Duration of ECA was prolonged in both male and female intoxicated cats. These findings indicate that: (1) similar to withdrawing men, ECA and LESP are elevated in withdrawing male cats; (2) ethanol-treated cats are an appropriate model for studying the mechanism of ethanol effects on esophageal motor function; (3) gender has a significant role in influencing the effects of alcohol.