HO-1 induction in the guinea-pig stomach: protection of smooth muscle functional performance during cobalt-induced oxidative stress.

Distribution and enzymatic activity of haem oxygenase (HO) was investigated in the stomach of healthy guinea pigs or animals subjected to in vivo cobalt-induced oxidative stress. The physiological role of HO-1 and HO-2 isoenzymes in fundic and antral area of the stomach was assessed by studying the action of HO substrate--hemin--on ionic currents of single smooth muscle cells. The data obtained suggest that HO-1 induction might serve in the guinea-pig stomach as genetically determined defense mechanism aimed to combat toxic stress-related pathology in order to preserve the functional performance of the organ.