Am. Svensson et al., PANCREATIC AND ISLET BLOOD-FLOW IN F-1-HYBRIDS OF THE NON-INSULIN-DEPENDENT DIABETIC GK-WISTAR RAT, European journal of endocrinology, 130(6), 1994, pp. 612-616
Previous studies have indicated that various conditions under which an
increased functional load is posed on the pancreatic islets, e.g. par
tial pancreatectomy and continuous glucose infusions, may influence th
e microcirculation of the pancreas. To investigate further the effects
of elevated functional demand on the islets, the blood perfusion of t
he whole pancreas and the pancreatic islets was measured with a micros
phere technique in an animal model presenting impaired glucose toleran
ce and mild hyperglycemia, namely F-1-hybrids of the spontaneously non
-insulin-dependent diabetic GK-Wistar rat. Normal Wistar rats served a
s controls. All hybrids had a pathological intraperitoneal glucose tol
erance test 1 week before the blood now measurements, which were perfo
rmed in 10-12-week-old rats. Both the whole pancreatic and the islet b
lood flows were increased in the hybrids compared to controls. The fra
ctional islet blood flow, i.e. the fraction of whole pancreatic blood
flow diverted through the islets, also was increased in the hybrid rat
s (12.6 +/- 0.6% vs 9.8 +/- 0.5% in controls, p<0.01). A bilateral abd
ominal vagotomy performed 30 min before the blood flow measurement mar
kedly decreased the blood flow values of the islets and the whole panc
reas in both groups of rats. After vagotomy, the islet blood now in th
e hybrid rats was similar to that of the vagotomized control animals (
8.2 +/- 0.8 and 7.5 +/- 1.4%, respectively). It is concluded that the
increased pancreatic and islet blood perfusion observed in F-1-hybrids
of the GK-Wistar rat depends on a mechanism mediated by the vagus ner
ve.