effect of acute consumption of paraoxon on basal and Pentagastrin-Stimulated Gastric acid and pepsin secretion in rats

ABSTRACT

Paraoxon is an organophosphate. Organophosphate inhibit acetylcholinestrase enzyme and cause nicotinic and muscarinic sings. There is no study on our knowledge regarding the effect of these substances on gastric acid and pepsin secretion. In the present study, the effect of acute consumption of paraoxon on gastric acid and pepsin secretion has been investigated. In the present study 30 female N-mari rats weighing 200-250gr were used. The first group [paraoxon] received 0.5mg/kg paraoxon intraperitonealy. The second group [alcohol] received the dozes of ethyl alcohol [96%] and the third group [control] received no drug. Animals were anesthetized by intraperitoneal injection of 50mg/kg Sodium thiopental. After trachesotomy and laparatomy gastric secretions were collected with a tube via duodenum. Pentagastrin [25 micro g/kg. ip] was used as gastric stimulator. Acid and pepsin secretions were measured by titration and Anson methods respectively. Stages of measurement were basal, stimulated. and re-basal. The basal acid secretion in control, alcohol and paraoxon groups was 7.6 +/- 0.26, 7.46 +/- 0.4 and 7.03 +/- 0.28 micro mol/15min respectively that shows no significant difference among three groups. Although following pentagastrin-stimulation acid secretion was significantly more than basal stage in all groups, but there was significantly more secretion in control than alcohol subjects. But there was no difference between control and paraoxon or alcohol and paraoxon groups in this regard. Regarding pepsin secretion, there was significantly more secretion in alcohol subjects than others in all measured stages. In comparison to control group, acute paraoxon has no effect on basal acid pepsin secretion, while acute alcohol caused a significant increase in basal acid/pepsin secretion