Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-6 Spec No
pubmed:dateCreated
1996-5-16
pubmed:abstractText
Brain sexual differentiation occurs during the steroid-sensitive phases in early development, and is affected particularly by exposure to oestrogens formed in the brain by aromatisation of androgen. The organisational effects of oestrogen result in male-specific neuronal morphology, control of reproductive behaviour, and patterns of gonadotrophin secretion. A question which still has to be resolved is what determines changes in aromatase activity effective for the differentiation of sexually dimorphic brain development during sensitive periods of growth. In the mouse, a sex difference exists at early stages of embryonic development in aromatase-containing neurones of the hypothalamus. The embryonic aromatase system is regulated later in foetal development by androgens. Testosterone treatment increases the numbers of aromatase-immunoreactive hypothalamic neuronal cell bodies. Kinetic evidence from studies on the avian brain suggest that endogenous steroid inhibitors of aromatase, probably formed within neuroglia, also have a role in the control of oestrogen production. Inhibitory kinetic constant determination of endogenous androgenic metabolites formed in the brain showed that preoptic aromatase is potently inhibited by 5 alpha-androstanedione(K(i)=6nM) and less strongly by 5 beta-dihydrotestosterone (K(i)=350nM). Regulation by steroidal and possibly non-steroidal inhibitors may contribute to the special characteristics and plasticity in aromatase activity which develops at certain stages in ontogeny.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0960-0760
pubmed:author
pubmed:issnType
Print
pubmed:volume
56
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
201-7
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:8603041-Androgens, pubmed-meshheading:8603041-Animals, pubmed-meshheading:8603041-Aromatase, pubmed-meshheading:8603041-Aromatase Inhibitors, pubmed-meshheading:8603041-Birds, pubmed-meshheading:8603041-Brain, pubmed-meshheading:8603041-Enzyme Inhibitors, pubmed-meshheading:8603041-Estrogens, pubmed-meshheading:8603041-Female, pubmed-meshheading:8603041-Gerbillinae, pubmed-meshheading:8603041-Male, pubmed-meshheading:8603041-Mice, pubmed-meshheading:8603041-Models, Biological, pubmed-meshheading:8603041-Nerve Tissue Proteins, pubmed-meshheading:8603041-Neuroglia, pubmed-meshheading:8603041-Oxidoreductases, pubmed-meshheading:8603041-Sex Characteristics, pubmed-meshheading:8603041-Sex Differentiation, pubmed-meshheading:8603041-Sexual Behavior, Animal, pubmed-meshheading:8603041-Testosterone
pubmed:year
1996
pubmed:articleTitle
Regulation of sex-specific formation of oestrogen in brain development: endogenous inhibitors of aromatase.
pubmed:affiliation
MRC Neuroendocrine Development and Behaviour Group, The Babraham Institute, Cambridge, U.K.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't