Semi-quantitative analysis of the effects of estrogen on CGRP- and methionine-enkephalin-immunoreactivity in the periventricular preoptic nucleus and the medial preoptic area of female rats.
The effects of 17 beta-estradiol (E2) on calcitonin gene-related peptide (CGRP)- and methionine-enkephalin (Met-Enk)-immunoreactive (IR) nerve fibers in the periventricular preoptic nucleus (Pe) and the medial preoptic area, including the medial preoptic nucleus (MPN), of the female rat were studied semi-quantitatively by using a computer-based image analysis system. The area occupied by CGRP- and Met-Enk-IR fibers was significantly increased in the Pe and the MPN after 28-day exposure to E2. Computer-based analysis of CGRP- and Met-Enk-IR fibers in an area of 50-microns intervals from the wall of the third ventricle showed a low flat histogram pattern in ovariectomized rats, but E2 treatment caused a diphasic pattern, corresponding to the Pe and the MPN, respectively. Since the Pe and the MPN contain a high population of estrogen receptors, it is suggested that E2 may have an influence on the neuronal configuration of afferent fibers to these areas.
Yuri
K
K
Department of Anatomy, Kyoto Prefectural University of Medicine, Japan.
Kawata
M
M
D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000032:analysis / Q000378:metabolism*; D002552:Cerebral Ventricles / Q000502:physiology; D004744:Enkephalin, Methionine / Q000032:analysis / Q000378:metabolism*; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D007150:Immunohistochemistry; D009412:Nerve Fibers / Q000187:drug effects / Q000502:physiology; D010052:Ovariectomy; D011301:Preoptic Area / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains
D004958:Estradiol; D004744:Enkephalin, Methionine; D015740:Calcitonin Gene-Related Peptide