These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Regulation of estrogen-induced uterine hyperemia and contractility in the guinea pig: cholinergic modulation of an alpha-adrenergic response.
    Author: Garris DR, Ingenito AJ, McConnaughey MM, Dar MS.
    Journal: Biol Reprod; 1984 May; 30(4):863-8. PubMed ID: 6329335.
    Abstract:
    The effects of estradiol (1 microgram: E-1) treatment on uterine hyperemia and uterine sensitivity to various biogenic compounds were evaluated in ovariectomized (OVX) animals treated with either sesame oil or E-1 for 3 days. The E-1 treatments induced significant elevations in uterine weight, blood flow, and alpha- and beta-receptor numbers as compared with oil-treated controls. In contrast, uterine norepinephrine (NE) levels were reduced in E-1-treated, OVX guinea pigs as compared with oil-treated controls. Uterine sensitivity and responsivity to NE (10(-6) M) and acetylcholine (ACH: 10(-8) M) were either comparable to, or enhanced, in E-1-treated animals as compared with controls. In particular, combined ACH-NE treatment induced a dramatic increase in contraction force in E-1-treated uteri as compared with uteri from oil-treated animals. The use of specific adrenergic alpha- (phentolamine: 10(-6) M) or beta- (propranolol: 10(-6) M) receptor blocking agents indicated that the estrogenic response was mediated via the alpha-adrenergic receptor complex. Since atropine (10(-8) M) effectively blocked the cholinergic accentuation of this uterine response, it is suggested that a cholinergic priming, or beta-receptor block, is necessary for the full expression of the alpha-adrenergic-mediated, estrogenic response in the guinea pig. The estrogen-associated increase in available alpha- and beta-receptors and depressed tissue NE levels probably account for both the hyperemic response and enhanced tissue sensitivity to biogenic compounds in the guinea pig.
    [Abstract] [Full Text] [Related] [New Search]