Partial pancreatectomy in rats causes an impairment of the glucose-induced stimulation of pancreatic islet blood flow.

Adult rats were subjected to either a sham operation (S-rats) or a 60% partial pancreatectomy (P-rats). Both P- and S-rats were normoglycemic and normoinsulinemic after surgery. Four weeks later, the animals were injected i.v. with 1 ml of either 0.9% (w/v) saline or 30% (w/v) D-glucose, and after 5 min whole pancreatic blood flow (PBF) and islet blood flow (IBF) were measured, using a microsphere technique. In the saline-injected P-rats both PBF and IBF values were higher than in S-rats (p less than 0.001 for both values). Administration of glucose had no effects on PBF in either S- or P-rats when compared to saline-injected animals. IBF was, however, markedly increased (p less than 0.01) by glucose in S-rats in comparison with saline-injected S-rats, whilst no difference in IBF was observed between glucose- and saline-injected P-rats. The fraction of PBF diverted through the islets (fIBF) was approximately 10% in S-rats and 20% in P-rats. Glucose increased fIBF in S-rats, but had no effect in P-rats. In conclusion, in S-rats a glucose-stimulated insulin release is accompanied by an increase in IBF, but this is not observed in P-rats.