Mapping of Glucocorticoid Receptor Immunoreactive Neurons in the Rat Tel- and Diencephalon Using a Monoclonal Antibody against Rat Liver Glucocorticoid Receptor*

Abstract

By means of a monoclonal antibody against the rat liver glucocorticoid receptor (GR) in combination with the indirect immunoperoxidase technique it has been possible to demonstrate GR-immunoreactive nerve and glial cell nuclei all over the tel- and diencephalon of the male rat. Strongly GR-immunoreactive nerve cell nuclei were only present in the parvocellular part of the paraventricular hypothalamic nucleus, in the anterior periventricular hypothalamic nucleus, in the ventral part of the mediobasal hypothalamus, and in the CA1 and CA2 subregion of the hippocampal formation. Within the paraventricular hypothalamic nucleus a substantial overlap exists between the GR-immunoreactive area and the CRF-immunoreactive area. Medium to high densities of moderately GR-immunoreactive nerve cell nuclei were present all over the cortical hemispheres. Medium densities of moderately GR-immunoreactive nerve cells were demonstrated in many thalamic nuclei and in the central amygdaloid nucleus. After adrenalectomy the GR immunoreactivity was predominantly located in the pericaryon. Upon acute corticosterone treatment of adrenalectomized male rats, the GR immunoreactivity was again mainly demonstrated in the nerve cell nuclei indicating that corticosterone can translocate GR from the cytoplasm to the cell nuclei. It is suggested that the hypothalamic GR may be involved in the regulation of especially CRF secretion but also in the secretion of other anterior pituitary hormones such as TRH and somatostatin.

Mineralocorticoid and glucocorticoid receptors in the brain. Implications for ion permeability and transmitter systems

“…Brain regions containing ACh-producing cells are quite sparse in their GR content (Fuxe et al, 1985). However, chronic (2 was observed in rat hippocampus but not caudate, both in vivo (Imperato et al, 1989) and in vitro (Gilad et al, , 1987.…”

“…The distribution of GR immunoreactivity (Fuxe et al, 1985;Van Eekelen et al, 1987a;Cintra et al, 1991;Ahima and Harlan, 1990) and GR mRNA (Aronsson et al, 1988;Van Eekelen et al, 1988;Chao et al, 1989) is much more widespread, in neurons and glial cells throughout the brain. Particularly high GR concentrations are found in the limbic system (hippocampus, septum) and in the parvocellular neurons of the PVN in the hypothalamus where glucocorticoids suppress the stress-induced synthesis of CRH and AVP.…”

“…The fact that GRs are present in neurons of the brainstem which produce monoamines and in neurons to which the monoaminergic areas project (Fuxe et al, 1985;Harfstrand et al, 1986) suggests that steroids interact with the central monoaminergic system. This is indeed true for some aspects, though not all, of the monoaminergic systems.…”

“…Many peptidergic neurons in the brain also contain GRs (Fuxe et al, 1985). A number of studies have therefore focussed on the question whether GR activation controls peptide production.…”

Glutamate NMDA Receptors within the Amygdala Participate in the Modulatory Effect of Glucocorticoids on Extinction of Conditioned Fear in Rats

“…As a synthetic glucocorticoid agonist, DEX can activate glucocorticoid receptors. The amygdala and hippocampus, specific to the extinction of conditioned fear, contain glucocorticoid receptors (Fuxe et al, 1985;Van Eekelen et al, 1987;Korte, 2001). There is also evidence that glucocorticoids alter calcium conductance and calcium channel subunit expression in BLA (Karst et al, 2002).…”