The human forebrain has discrete estrogen receptor alpha messenger RNA expression: High levels in the amygdaloid complex

Estrogen is considered to play an important role in neuropsychiatric disord ers and the estrogen receptors mediate the action of the hormone. In the pr esent study, the messenger RNA expression pattern of the estrogen receptor alpha subtype was identified in the post mortem human brain. High stringent in situ hybridization histochemistry was performed using a riboprobe speci fic for the estrogen receptor cu subtype. The human brain was mainly charac terized by abundant estrogen receptor alpha messenger RNA expression in the amygdala and hypothalamus, but labeling (lower) was also found in the exte nded sublenticular amygdala, cerebral cortex, and hippocampus. In the amygd ala, the estrogen receptor alpha messenger RNA was preferentially expressed in medially-localized nuclei suggesting that estrogen regulates distinct h uman amygdala-mediated functions. The Cynomologous monkey brain was also ex amined in the present study and a similar distribution of the estrogen rece ptor a messenger RNA signal was observed in the human and monkey brain. How ever, the primate expression pattern differed in part from the known distri bution in the rat. The current results show that estrogen receptor alpha messenger RNA is expr essed in discrete areas of the human brain not only related to neuroendocri ne function, but also emotion, memory, and cognition, which is consistent w ith the hypothesized involvement of estrogen in schizophrenia, affective di sorders, and Alzheimers disease. (C) 1999 IBRO. Published by Elsevier Scien ce Ltd.