PROSTAGLANDINS AND 5-HT RESPONSE ON GASTRIC SECRETION IN ALBINO RATS

Prostaglandins (PGE1 ) 0.1, 0.2 and 0.4 mg/kg and 5-hydroxytryptamine (5-HT) 1, 2.5 and 5 mg/kg dose dependently inhibited gastric secretion in pyloric legated rats model While PGF2 ∝ 0.1, 0.4 and 1mg/kg inhibited gastric acid secretion. Methysergide in the dose 0.05 mg/kg significantly stimulated the gastric secretion. When non-inhibitory dose of PGE1 (0.1 ) and 5-HT (1.0 mg/kg) are injected simultaneously there were potentiation of inhibitory activity on gastric secretary response on volume, acid output, chloride output and pepsin output. The inhibitory activity of both PGE1 (0.4 mg/ kg) and 5-HT (5.0 mg/kg) including the inhibitory potentiating activity could not be modified by the pretreatment of methysergide (0.05 mg/kg). Similarly stimulatory dose of PGF2 ∝ (0.4) mg/kg) and inhibitory dose of PGE1 (0.4 mg/kg) administered together inhibitory response of PGE1 (0.4 mg/kg) were also not modified by methysergide pretreatment.