Glucocorticoid receptor immunoreactivity in monoaminergic neurons of rat brain

A monoclonal antibody against the rat liver glucocorticoid receptor was used in combination with rabbit antibodies against tyrosine hydroxylase, phenylethanolamine N-methyltransferase, and 5-hydroxytryptamine to demonstrate strong glucocorticoid receptor immunoreactivity in large numbers of central monoaminergic nerve cell bodies of the male rat. The receptor immunoreactivity was predominantly located in the nucleus, whereas the tyrosine hydroxylase, phenylethanolamine N-methyltransferase, and 5-hydroxytryptamine were detected mainly in the cytoplasm. The vast majority of the noradrenergic nerve cell bodies of groups A1-A7 and of the 5-hydroxytryptaminergic cell bodies of groups B1-B9 were found to contain strong glucocorticoid receptor immunoreactivity. The majority of the phenylethanolamine N-methyltransferase-immunoreactive nerve cells of the adrenergic cell groups C1-C3 and of the dorsal subnuclei of the nucleus tractus solitarius in the medulla oblongata were also strongly immunoreactive for glucocorticoid receptor. In the midbrain dopaminergic groups A8-A10, moderately (A8, A9) to strongly (A10) glucocorticoid receptor-immunoreactive cells were found, ranging from 40 to 75% of the total population. In the hypothalamic dopaminergic cell groups, all the cells of groups A12 and A14, as well as the majority of the dopaminergic cells of the zona incerta (A13), were found to contain moderate to strong glucocorticoid receptor immunoreactivity, but none of the large dopaminergic cells of the posterior hypothalamus (A11) showed such immunoreactivity.