Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1996-10-16
pubmed:abstractText
After i.v. oCRH, plasma immunoreactive ACTH (ACTH-IR) is significantly greater in blacks than in whites; however, there is no corresponding increase in cortisol secretion. To test the hypothesis that there are black-white differences in adrenal responsiveness to ACTH that underlie this phenomenon, weight-, age-, and education-matched black (n = 10) and white (n = 10) women were i.v. infused with 5 differing doses of ACTH1-24 (0, 0.003, 0.01, 0.1, and 1 microgram/kg) with measured plasma cortisol and DHEA. To test the alternative hypothesis that greater post-CRH plasma ACTH-IR in blacks is caused by qualitative differences in circulating ACTH-immunoreactive peptides, we collected pre- and post-CRH plasma from 5 black and 5 white women and measured ACTH-IR after sample fractionation, using high-pressure liquid chromatography. There were no racial differences in adrenal responsiveness to differing doses of ACTH1-24 and no differences in the distribution of the forms of ACTH-IR before CRH. After CRH, whites had predominant ACTH-IR peaks at the retention times of ACTH1-39 and ACTH1-39-sulfoxide, whereas blacks had prominent peaks at several additional retention times. The post-CRH ratio of intact to total ACTH was significantly lower in blacks than in whites (0.27 +/- 0.17 vs. 0.71 +/- 0.17, P < 0.003). We conclude that there are qualitative differences in post-CRH circulating ACTH-IR in blacks and whites, leading to a greater immunoreactive to bioactive ACTH ratio in blacks. Such differences in the circulating forms of ACTH can account for greater CRH-stimulated ACTH-IR in blacks.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0021-972X
pubmed:author
pubmed:issnType
Print
pubmed:volume
81
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3307-11
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Etiology of the differences in corticotropin-releasing hormone-induced adrenocorticotropin secretion of black and white women.
pubmed:affiliation
Clinical Center, National Institute of Child Health & Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
pubmed:publicationType
Journal Article, Comparative Study