Biochemical changes in the pancreas of rats with chronic renal failure.

Chronic renal failure (CRF) was produced in female Sprague-Dawley rats by 7/8 nephrectomy. Creatinine clearance was depressed significantly (P less than 0.005) and blood urea nitrogen (BUN) increased in CRF rats when compared with the sham-operated (S) controls. CRF caused no apparent change in body weight but significantly increased pancreatic weight as well as increased DNA, RNA, and protein content. Pancreatic protein-to-DNA and RNA-to-DNA ratios were also found to be significantly higher in CRF rats than in the S controls. Trypsin-like activity and immunoreactive cationic trypsinogen levels were both increased in the pancreas of CRF rats, but not in their serum. On the other hand, protease inhibitory activity in the pancreas and serum was significantly decreased by CRF. The ability of the dispersed pancreatic acini isolated from CRF rats to incorporate [3H]-leucine into protein, in the absence and presence of 0.25 nM cholecystokinin octapeptide (CCK-8), was found to be lower than in the controls. Furthermore, discharge of both trypsinogen and chymotrypsinogen induced by CCK-8 was markedly reduced from acini of CRF rats as compared with the S controls. In contrast, lactate dehydrogenase (LDH) was released more readily from pancreatic acini of CRF. It is concluded that mild CRF produces hyperplasia and hypertrophy of the pancreas and lowers the responsiveness of acini to CCK-8 with respect to synthesis and secretion of proteins.