The brain is an important target organ for circulating steroid hormones secreted from peripheral organs such as the adrenal cortex
testis and/or ovary. In other words
these peripheral organs control the central nervous system. Steroid hormones substantially influence brain development
reproduction
sexual differentiation
cognition
memory
behavior
and so on. These effects are mediated by steroid hormone receptors
which directly regulate gene expression. The steroid hormone receptor superfamily is an intracellular ligand-regulated transcription factor. All members
including the glucocorticoid receptors (GR)
mineralocoroticoid receptors (MR)
estrogen receptors (ER)
progesterone receptors (PR) and androgen receptor (AR)
mediate the expression of a gene by binding to hormone responsive elements (HREs) as dimmers in a ligand-dependent manner. In particular
steroid hormones have an important role for the regulating neurons and cells
which are associated with the neuroendocrine and endocrine regulation system
because many neuroendocrine neurons and cells express the steroid hormone receptors
such as estrogen receptor (ER)
androgen receptor (AR) and corticosteroid receptors. In this review
first the localization of GR and MR immunoreactivities in the brain is introduced
and secondly
the effects of change of GR expression in neurons are examined by several morphological approaches. Third
the interaction of GR expression and pituitary cell function is introduced. Finally
the recent topics on the control system of feeding regulation in the central nervous system
which also closely involves steroid hormone action
are discussed.
