Effect of severe stress on the gastric motor activity: canine study of mechanism of action.

BACKGROUND

Increased gastric motility was observed during restraint stress in animals; however, mechanism of action could not be traced in literature. We investigated the hypothesis that high levels of stressful cutaneous stimuli induce increase of gastric motor activity through a reflex action.

METHODS

Gastric tone (GT) was assessed in 14 dogs by barostat system consisting of balloon-ended tube connected to strain gauge and air-injection system. Tube was introduced into stomach and its balloon inflated with 150 mL of air. Thermal cutaneous stimulation (TCS) was performed by thermal plate applied to skin. Temperature was raised in increments of 5 degrees C up to 107 degrees C and GT was simultaneously assessed by recording balloon volume variations expressed as percentage change from baseline volume. Test was repeated after separate anesthetization of skin and stomach.

RESULTS

TCS up to mean temperature of 48.7 +/- 1.1 degrees C effected significant decrease of GT, but significant increase beyond this temperature. Twenty minutes after individual anesthetization of skin and stomach, TCS produced no significant change in GT.

CONCLUSION

TCS up to certain degree effected GT decrease, whereas TCS beyond this degree augmented the GT. These effects seem to be mediated through reflex action as evidenced by their absence on individual anesthetization of the suggested 2 arms of the reflex arc: skin and stomach; we call this reflex "cutaneo-gastric reflex." The reflex may have the potential to serve as an investigative tool in diagnosis of gastric motor disorders provided further studies are performed to reproduce current results.