DISSOCIATION OF ANORECTIC AND AFFECTIVE RESPONSES TO EPINEPHRINE AND GLUCOSE IN RATS

The purpose of this study was to determine whether the anorexia follow ing epinephrine and glucose IP injections is due to the activation of mechanisms of satiety. Epinephrine (100 mu g . kg(-1)) and glucose (4 g . kg(-1)) were injected IP in rats. In control sessions for epinephr ine test, rats received IP saline, and IM epinephrine. In control sess ions for the glucose test, rats received IP NaCl, isoosmotic to the gl ucose solution. Food intake or taste reactivity to a sucrose solution was recorded after these treatments. Epinephrine and glucose decreased food intake by 75% (p < 0.001), and 49% (p < 0.01), compared to their controls. No change of taste reactivity responses was observed with a ny of these treatments. Twelve-hour fasting did not modify the general taste reactivity responses when compared to the responses evoked in r ats fed ad lib. These results might be explained by the fact that anor exia could be obtained by a suppression of hunger without the activati on of the mechanisms of satiety. This in turn would imply a possible d issociation between the signals and physiological pathways normally in volved in hunger and satiety.