Hdl Handle:
http://hdl.handle.net/10675.2/129
Title:
Activation of the kinin system in the ovary during ovulation: role of endogenous progesterone.
Authors:
Brann, Darrell W ( 0000-0002-4480-8859 ) ; Greenbaum, Lowell M; Mahesh, Virendra B; Gao, XiaoXing
Abstract:
BACKGROUND: Previous work by our group and others has implicated a role for kinins in the ovulatory process. The purpose of the present study was to elucidate whether endogenous progesterone, which is an intraovarian regulator of ovulation, might be responsible for induction of the kinin system in the ovary during ovulation. The gonadotropin-primed immature rat was used as the experimental model, and the role of endogenous progesterone was explored using the antiprogestin, RU486. RESULTS: The results of the study revealed that RU486 treatment, as expected, significantly attenuated ovulation. Activity of the kinin-generating enzyme, kallikrein, was elevated in the ovary in control animals prior to ovulation with peak values observed at 4 h post hCG, only to fall to low levels at 10 h, with a recovery at 20 h post hCG. RU486 treatment had no significant effect on ovarian kallikrein activity as compared to the control group. Total ovarian kininogen levels in control animals increased significantly at 12-14 h after hCG - coinciding with initiation of ovulation. Thereafter, ovarian kininogen levels fell to low levels at 20 h, only to show a rebound from 24-38 h post-hCG. RU486 treatment had no significant effect on the rise of total ovarian kininogen levels from 12-14 h after hCG; however, from 30-40 h post hCG, RU486-treated animals had significantly higher total ovarian kininogen levels versus control animals, suggesting that endogenous progesterone may act to restrain elevations of kininogens in the post-ovulatory ovary. This robust elevation of ovarian kininogen levels by RU486 was found to be primarily due to an increase in T-kininogen, which is a potent cysteine protease inhibitor. CONCLUSIONS: Taken as a whole, these results suggest that endogenous progesterone does not regulate kallikrein activity or kininogens prior to ovulation, but may provide a restraining effect on T-kininogen levels in the post-ovulatory ovary.
Citation:
BMC Physiol. 2002 Apr 29; 2:7
Issue Date:
29-Oct-2003
URI:
http://hdl.handle.net/10675.2/129
PubMed ID:
12014992
PubMed Central ID:
PMC111191
Type:
Journal Article; Research Support, Non-U.S. Gov't
ISSN:
1472-6793
Appears in Collections:
Department of Pharmacology and Toxicology: Faculty Research and Presentations

Full metadata record

DC FieldValue Language
dc.contributor.authorBrann, Darrell Wen_US
dc.contributor.authorGreenbaum, Lowell Men_US
dc.contributor.authorMahesh, Virendra Ben_US
dc.contributor.authorGao, XiaoXingen_US
dc.date.accessioned2010-09-24T22:03:24Z-
dc.date.available2010-09-24T22:03:24Z-
dc.date.issued2003-10-29en_US
dc.identifier.citationBMC Physiol. 2002 Apr 29; 2:7en_US
dc.identifier.issn1472-6793en_US
dc.identifier.pmid12014992en_US
dc.identifier.urihttp://hdl.handle.net/10675.2/129-
dc.description.abstractBACKGROUND: Previous work by our group and others has implicated a role for kinins in the ovulatory process. The purpose of the present study was to elucidate whether endogenous progesterone, which is an intraovarian regulator of ovulation, might be responsible for induction of the kinin system in the ovary during ovulation. The gonadotropin-primed immature rat was used as the experimental model, and the role of endogenous progesterone was explored using the antiprogestin, RU486. RESULTS: The results of the study revealed that RU486 treatment, as expected, significantly attenuated ovulation. Activity of the kinin-generating enzyme, kallikrein, was elevated in the ovary in control animals prior to ovulation with peak values observed at 4 h post hCG, only to fall to low levels at 10 h, with a recovery at 20 h post hCG. RU486 treatment had no significant effect on ovarian kallikrein activity as compared to the control group. Total ovarian kininogen levels in control animals increased significantly at 12-14 h after hCG - coinciding with initiation of ovulation. Thereafter, ovarian kininogen levels fell to low levels at 20 h, only to show a rebound from 24-38 h post-hCG. RU486 treatment had no significant effect on the rise of total ovarian kininogen levels from 12-14 h after hCG; however, from 30-40 h post hCG, RU486-treated animals had significantly higher total ovarian kininogen levels versus control animals, suggesting that endogenous progesterone may act to restrain elevations of kininogens in the post-ovulatory ovary. This robust elevation of ovarian kininogen levels by RU486 was found to be primarily due to an increase in T-kininogen, which is a potent cysteine protease inhibitor. CONCLUSIONS: Taken as a whole, these results suggest that endogenous progesterone does not regulate kallikrein activity or kininogens prior to ovulation, but may provide a restraining effect on T-kininogen levels in the post-ovulatory ovary.en_US
dc.rightsThe PMC Open Access Subset is a relatively small part of the total collection of articles in PMC. Articles in the PMC Open Access Subset are still protected by copyright, but are made available under a Creative Commons or similar license that generally allows more liberal redistribution and reuse than a traditional copyrighted work. Please refer to the license statement in each article for specific terms of use. The license terms are not identical for all articles in this subset.en_US
dc.subject.meshAnimalsen_US
dc.subject.meshChorionic Gonadotropin / pharmacologyen_US
dc.subject.meshDrug Combinationsen_US
dc.subject.meshFemaleen_US
dc.subject.meshGonadotropins, Equine / pharmacologyen_US
dc.subject.meshHormone Antagonists / pharmacologyen_US
dc.subject.meshKallikrein-Kinin System / drug effects / physiologyen_US
dc.subject.meshMifepristone / pharmacologyen_US
dc.subject.meshOvary / drug effects / physiologyen_US
dc.subject.meshOvulation / drug effects / physiologyen_US
dc.subject.meshProgesterone / antagonists & inhibitors / physiologyen_US
dc.subject.meshRatsen_US
dc.subject.meshRats, Sprague-Dawleyen_US
dc.titleActivation of the kinin system in the ovary during ovulation: role of endogenous progesterone.en_US
dc.typeJournal Articleen_US
dc.typeResearch Support, Non-U.S. Gov'ten_US
dc.identifier.pmcidPMC111191en_US
dc.contributor.corporatenameDepartment of Pharmacology and Toxicologyen_US
dc.contributor.corporatenameDepartment of Physiologyen_US
dc.contributor.corporatenameDepartment of Surgeryen_US
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