Restraint Plus Water-immersion Stress (RWIS)-induced Stomach Ulcers in Mice are Depressed by a Conditioning Heat Treatment

Abstract

A conditioning mild heat treatment can depress subsequent severe heat-induced biological damage by inducing thermal tolerance. In the work described here, the effect of a conditioning mild heat exposure at 37°C was examined on the formation of gastric mucosa damage induced by a restraint plus water-immersion stress (RWIS) treatment in mice. RWIS treatments induced stomach ulcers in about 42% of the control animals, but a mild conditioning heat treatment at 37°C was found to depress the appearance of ulcers, and only about 9% of the pre-exposed animals developed ulcers. In addition, RWIS treatment induced an apoptosis rate in the stomach of about 13%, but a conditioning mild heat treatment depressed the apoptotic rate to about 8%. Since the heat shock protein (HSP) inducer geranylgeranylacetone (GGA) also efficiently depressed stomach ulcer incidence rates, it is suggested that gastric mucosa damage may be depressed by HSPs induced by a mild conditioning heat treatment through the depression of apoptosis.