Effect of thermal cutaneous stimulation on the gastric motor activity: Study of the mechanism of action

Abstract

To investigate the mechanism of action of thermal cutaneous stimulation on the gastric motor inhibition. The gastric tone of 33 healthy volunteers (20 men, mean age 36.7 +/- 8.4 years) was assessed by a barostat system consisting of a balloon-ended tube connected to a strain gauge and air-injection system. The tube was introduced into the stomach and the balloon was inflated with 300 mL of air. The skin temperature was elevated in increments of 3 degree up to 49 degree and the gastric tone was simultaneously assessed by recording the balloon volume variations expressed as the percentage change from the baseline volume. The test was repeated after separate anesthetization of the skin and stomach with lidocaine and after using normal saline instead of lidocaine. Thermal cutaneous stimulation resulted in a significant decrease of gastric tone 61.2% +/- 10.3% of the mean baseline volume. Mean latency was 25.6 +/- 1.2 ms. After 20 min of individual anesthetization of the skin and stomach, thermal cutaneous stimulation produced no significant change in gastric tone. Decrease in the gastric tone in response to thermal cutaneous stimulation suggests a reflex relationship which was absent on individual anesthetization of the 2 possible arms of the reflex arc: the skin and the stomach. We call this relationship the "cutaneo-gastric inhibitory reflex". This reflex may have the potential to serve as an investigative tool in the diagnosis of gastric motor disorders, provided further studies are performed in this respect.