Estrogen affects the expression of Ca2+/calmodulin-dependent protein kinase IV in amygdala

We examined the effects of long-term estradiol benzoate (E2) treatment on protein expression of Ca2+/calmodulin-dependent protein kinase IV (CaMK IV) in the amygdala of ovariectomized (OVX) rats. Western blot analysis revealed increased protein levels of CaMK IV in the nuclear but not in the membranal or cystolic fraction of total amygdala in E2-treated compared to OVX rats. Significant increases in levels of CaM kinase IV gold immunolabeling were seen in the medial and basomedial, but not in the central or basolateral, amygdala of E2 compared to OVX rats, indicating the neuroanatomical heterogeneity of the E2 effect. These results suggest that CaMK IV may act as a molecular target for actions of estrogen in the amygdala of rats.