LOWER DENSITY OF ANTRAL SOMATOSTATIN-IMMUNOREACTIVE CELLS IN THE DIGESTIVE FORM OF CHRONIC CHAGAS-DISEASE

Patients with the digestive form of chronic Chagas' disease exhibit ab normally increased gastrin release, possibly caused by antral gastrin cell (G cell) hyperfunction. In order to identify the mechanisms under lying this abnormality, we used an immunohistochemical method to asses s the population of antral somatostatin-producing cells (D cells) in c hagasic patients, since somatostatin is known to be the main inhibitor y factor of gastrin secretion. Samples (N = 11) of endoscopic antral b iopsies taken from 16 Chagas' disease patients and 13 control subjects were studied. Antral D and G cell populations were determined by an i mmunohistochemical technique using highly specific antibodies against somatostatin and gastrin. There was no significant difference between Chagas' disease and control groups regarding G cell population (number of cells/mm reported as median (range): 70.0 (23.7-247.0) vs 98.1 (52 .7-169.4), P>0.10). In contrast, the number of antral D cells in Chaga s' disease patients was significantly lower than in controls (16.4 (6. 9-54.4) vs 59.3 (29.6-113.8), P<0.05). Chronic superficial gastritis a nd infection with Helicobacter pylori were more frequent in chagasic p atients than in controls, but there was no demonstrable association be tween these factors and the reduction of the number of antral D cells. These data suggest that reduction in the number of antral somatostati n-producing cells, which should lead to reduced inhibition of gastrin cell activity, may play a role in the increased gastrin secretion obse rved in Chagas' disease patients.