VAGOTOMY IN YOUNG OBESE HYPERGLYCEMIC MICE - EFFECTS ON SYNDROME DEVELOPMENT AND ISLET PROLIFERATION

Obese hyperglycemic mice have large pancreatic islets and high levels of serum insulin and blood glucose. Vagotomy was performed on 3-wk-old animals to investigate the role of gut cholinergic innervation in you ng Ume (a) over circle ob/ob mice. After vagotomy, obesity and hypergl ycemia are dissociated. Weight increase in obese vagotomized mice was lower than in sham-operated controls during the Ist wk postoperatively but not thereafter Blood glucose was lower up to 5 mo after vagotomy, but vagotomized mice showed reduced glucose tolerance. Islet cell pro liferation rate was reduced 2 and 3 wk but not 5 mo after vagotomy. Af ter 5 mo, islet volume was smaller in vagotomized mice. Serum insulin levels were the same in vagotomized animals as in sham-operated contro ls. The effects of reduced cholinergic innervation are probably caused both by direct effects of denervation and by lowered metabolic demand .