N. Atef et al., CNS INVOLVEMENT IN THE GLUCOSE-INDUCED INCREASE OF ISLET BLOOD-FLOW IN OBESE ZUCKER RATS, International journal of obesity, 19(2), 1995, pp. 103-107
OBJECTIVES: The aim of this work was to study the role of the central
nervous system in the glucose-induced increase in islet blood flow in
obese Zucker rats. DESIGN: A small amount of glucose (9 mg/kg) was inj
ected towards the brain via the left carotid artery in lean obese rats
either intact or vagotomized and after a pretreatment with clonidine.
RESULTS: Glucose injection induced a significant increase in plasma i
nsulin level and islet blood flow without a significant change in plas
ma glucose concentration in both lean and obese rats. Prior vagotomy o
r clonidine injection resulted in a decrease in glucose-induced islet
blood flow. Both the effect of glucose and its reversal were more pron
ounced in obese rats. CONCLUSION: In obese rats, an alteration of the
CNS could result in an increase in the parasympathetic tone and a decr
ease in the sympathetic one. These alterations would in turn contribut
e to the modifications in islet blood flow.