The effect of an intraperitoneal injection of melatonin on serum amylase levels in acute pancreatitis.

CONTEXT Several experimental studies have been carried out to explain the physiopathological mechanisms and to introduce endocrinological, enzymatic, biochemical and histopathological changes in organisms during acute pancreatitis. OBJECTIVE To evaluate the effect of an intraperitoneal injection of melatonin on serum amylase levels. DESIGN Experimental acute pancreatitis was experimentally caused through pancreatic duct ligation in 20 Winstar Albino rats. The rats were then divided into two groups: control and melatonin groups. INTERVENTION The serum amylase level was measured on the 7th day after acute pancreatitis had developed. In the melatonin group, an intraperitoneal injection of melatonin (20 mg/kg/day) was performed starting from the 2(nd) day after pancreatic duct ligation. MAIN OUTCOME MEASURE The levels of serum amylase were measured with an auto analyzer. RESULTS It was found that the mean (+/-SD) level of serum amylase in the control group was 947+/-182 IU/mL while it was 358+/-177 IU/mL in the experimental group (P<0.001). CONCLUSIONS The 20 mg/kg/day intraperitoneal injection of melatonin which was carried out for one week attenuated the serum amylase levels to a statistically significant degree. The researchers believe that intraperitoneal injections of melatonin decrease the severity of acute pancreatitis.