Glycogen phosphorylase reactivity in the amygdala and bed nucleus of the stria terminalis

The present study examines the reactivity of the glial metabolic enzyme, glycogen phosphorylase, within the amygdala and bed nucleus of the stria terminalis. Reactivity for phosphorylase a, the active form of glycogen phosphorylase, was higher in all parts of the medial amygdaloid nucleus, in the medial division of the central amygdaloid nucleus, in the anterior amygdaloid area and in the bed nucleus of stria terminalis than in all parts of the lateral amygdaloid nucleus, the anterior cortical amygdaloid nucleus, the posteromedial and posterolateral cortical amygdaloid nuclei, the intercalated nucleus of the amygdala, main part and the intercalated nuclei. A greater degree of phosphorylase a reactivity was also observed in the basolateral amygdaloid nucleus, anterior and posterior parts, and in the basomedial amygdaloid nucleus, anterior part, while other parts of these nuclei were less reactive. Reactivity attributed to total glycogen phosphorylase enzyme, phosphorylase a+phosphorylase b activated by AMP, was higher and homogeneous across the amygdala. Phosphorylase a patterns are likely to reflect differences in the contribution of glycogenolysis to the metabolic support of cells in the amygdala and bed nucleus of the stria terminalis. Possible relationships to local neuronal activity and to differences in glycogenolytic neuromodulatory input are discussed.