XXXX of VMH: effects on plasma insulin, @entity28 , and hyperreactivity.

@entity28 @entity146 @entity75 @entity7298 @entity3190 @entity1017 @entity5702 @entity35 @entity902
@entity28 resulting from lesions of the ventromedial hypothalamus (VMH) has often been attributed to ablation-induced disinhibition of insulin release. However, lesion studies have generally employed electrolyzing anodal current with stainless steel electrodes, which results not only in tissue ablation but deposits of metallic ions that can chronically irritate surrounding tissue. The present study compared the effects of irritative and nonirritative VMH lesions on plasma insulin levels and @entity28 in female @entity35 . Blood samples were obtained after a 4-h fast and 17 min after the initiation of a meal (6 ml of sweetened milk in 7 min) during a period when VMH @entity35 were food restricted to the level of sham-operated animals and again when all animals were fed ad libitum. Irritative lesions (anodal electrolytic with stainless steel electrodes) caused heavy metallic ion deposition at the lesion site, marked @entity28 , and @entity3190 both during food restriction and ad libitum feeding. @entity75 (cathodal electrolytic with @entity902 electrodes) resulted in no metallic ion deposition in seven of nine animals. These seven @entity35 , which displayed 65% of the @entity1017 of animals with @entity146 (significantly greater than sham @entity35 ), had significantly elevated insulin levels only under the postabsorptive condition during ad libitum feeding. In addition, only the animals with @entity146 displayed emotional hyperreactivity to capture and handling. It is concluded that @entity28 produced by anodal electrolytic lesions with stainless steel electrodes is a result of both a destructive component resulting in @entity7298 with @entity3190 and an irritative component (accounting for up to 40% of the @entity1017 in female @entity35 ) resulting in @entity5702 independent of @entity7298 .(ABSTRACT TRUNCATED AT 250 WORDS)
