Adaptive changes of the exocrine pancreas and plasma cholecystokinin release following subtotal gastric resection in rats.

This study was performed to investigate adaptive changes of the exocrine pancreas occurring after distal gastric resection by different procedures: Billroth I (BI) and Billroth II (BII). Sixty-four male Wistar rats were used and divided into four groups: controls (n = 16), sham-operated (n = 16), BI (n = 16) and BII (n = 16) subtotal gastric resection. Both procedures of subtotal gastric resection showed an organotrophic effect on the pancreas after 2 weeks: pancreatic weight in BI- and BII-operated rats increased by 23 and 35% and DNA content by 36 and 27%, respectively, compared to controls (p less than 0.001). After 4 weeks a further increase in pancreatic weight (46%), DNA content (52%) and protein content (58%) was found in BII rats. Trypsin and amylase content were increased in BI rats after 2 weeks (p less than 0.01). No parallel changes were observed in the enzyme content of BII rats as trypsin increased by over 200%, amylase by over 100% and lipase remained unaffected. Hormonal studies were carried out in 36 rats divided into groups as above. Basal and stimulated plasma levels of gastrin were reduced (p less than 0.01) following both types of subtotal gastric resection (p less than 0.01). Basal cholecystokinin (CCK) plasma levels did not differ between operated and control rats. Following the test meal CCK plasma levels were significantly increased after BII gastric resection (p less than 0.001) and BI gastric resection (p less than 0.01) compared to controls.