Influence of Repeated Anoxia,Electroshock and Insulin Hypoglycemia on Reactivity of Sympathetico-Adrenal System. ∗

Summary and Conclusions

The action of a standard anoxia test involving 5 periods of 25 minutes each at 280 mm Hg was used as a method to evaluate the responsiveness of the centers of the sympathetico-adrenal and vago-insulin systems on the basis of blood sugar determinations. It was found that repeated convulsions induced electrically, increased greatly the hyperglycemic response of rats to the standard test. This is interpreted as a sign of increased reactivity of the sympathetico-adrenal system and is accompanied by a marked dominance of this system as compared to the vago-insulin system. Similar results were obtained after frequent exposures to prolonged anoxia. However, repeated insulin comas failed to bring about this shift and showed actually a diminished or no hyperglycemic response to the standard anoxia test. It was shown that in these rats the administration of adrenalin failed to induce glycogenosis, which explains the reduction in the hyperglycemic response. Whether the reactivity of the centers of the sympathetico-adrenal systems is increased, as it seems to be by prolonged anoxia and electroshock, will be determined in another investigation by more direct methods. The effects described in this paper were reversible after an interval of 2 to 5 weeks. The work on anoxia and electroshock lends support to the idea that procedures similar to those used in the “shock therapy” of mental disease increase the reactivity of the centers of the sympathetico-adrenal system.