Abstract
Overexpression of α2A-adrenoceptors contributes to type 2 diabetes in GK rats. We aimed to investigate
if α2-adrenoceptor inhibition affected islet blood flow in these rats. Anesthetized GK
and Wistar-F rats were given the α2-adrenoceptor inhibitor yohimbine (2.5 mg/kg BW) intravenously. The GK rats had higher
blood glucose and serum insulin concentrations than WF rats. Yohimbine affected neither
of these values in WF rats, but decreased blood glucose and increased serum insulin
concentrations in GK rats. Total pancreatic and islet blood flows, measured with microspheres,
were increased in GK when compared to WF rats. Yohimbine affected none of the blood
flow values in WF rats, whereas islet blood flow in GK rats was reduced to values
similar to those seen in WF rats. Overexpression of α2-adrenoceptors may contribute to the increased islet blood flow seen in GK rats, and
may be eligible for pharmacologic intervention.
