Protective effect of zinc acexamate on experimental gastric ulcers: a histochemical study.

The antiulcerogenic effect of zinc acexamate on gastric ulcers induced by reserpine and changes in the morphology of gastric mucosa were studied in rats by histochemical methods. Histochemistry revealed that zinc acexamate preserved reserpine-depleted neutral and acid glycoproteins. ATPase reaction remained strong in nearly normal periglandular capillaries. The reaction intensity of SDH and NADH2-tetrazolium reductase, and the number and size of the DH-positive parietal cells were decreased, illustrating the decline of energy metabolism involved in acid secretion. The decreased height and weaker staining of the pyroninophile chief cell layer corresponded to the lower amount of RNA, an indirect indicator of pepsinogen synthesis. The significant correlation indices "r" between the severity of gastric lesions and histochemical parameters of the defensive (glycoproteins and microvascular ATPase) and aggressive factors (parietal cell DH and chief cell RNA) confirmed the pathogenic effect of reserpine and the protection provided by zinc acexamate. These findings confirm the multifactorial mechanism of action described for zinc acexamate in several previous works.