<qa>  What is the main protein kinase isozymes in rats treated with lithiumBipolar Affective Disorder remains an illness with high morbidity and mortality. Mood stabilizers such as lithium and sodium valproate have been described as having their anti-manic effect by targeting protein kinase C PKC isozymes Manji and Lenos, 1999. In rats chronically treated with lithium, there is a reduction of the major PKC substrate MARCKS and a reduction in the hippocampus of the expression of two protein kinase isozymes, alpha and epsilon. Manji et al. 1999 further postulated that PKC inhibitors such as tamoxifen and other estrogen antagonists might represent a novel class of therapeutic agents for the treatment of mania. 