{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/23613"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/23613","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Induction of the oxytocin receptor and its role in luteolysis in sheep","abstract":"The objectives in this study were to evaluate the influence of withdrawal of progesterone on induction of the uterine oxytocin receptor in the absence and presence of estradiol and to determine whether or not estradiol of ovarian follicular origin is necessary for induction of the oxytocin receptor and the pulsatile secretion of prostaglandin F$\\sb{2\\alpha}$ (PGF$\\sb{2\\alpha}$) during spontaneous luteolysis. Continuous treatment with progesterone for 9 or 12 days reduced the density of oxytocin receptors in endometrium and myometrium when compared to the vehicle-treated groups. In the endometrium, withdrawal of progesterone after day 9 resulted in an increase in the concentration of oxytocin receptor on day 13 (P $<$ 0.01) and estradiol enhanced the effects of progesterone withdrawal (P $<$ 0.01). Otherwise, the effect of estradiol was to reduce oxytocin receptor concentrations (P $<$ 0.01). X-irradiation prolonged the luteal phase of the estrous cycle. Estradiol treatment reversed the effects of X-irradiation and shortened the estrous cycle when compared to the ewes which received sham X-irradiation and placebos. About 50 percent of PGFM peaks overlapped with oxytocin peaks and no difference in the percentage of overlapped PGFM peaks was observed between estradiol-treated ewes and the ewes receiving placebos. Estradiol treatment decreased the interval between PGFM peaks (P $<$ 0.01) and increased the interval between oxytocin peaks (P $<$ 0.01). Lower concentrations of oxytocin receptor in the endometrium (P $<$ 0.01) but higher concentrations of oxytocin receptor in the myometrium (P $<$ 0.01) were observed in estradiol-treated ewes when compared to the ewes treated with placebos. In conclusion, withdrawal of progesterone induces the formation of oxytocin receptor in endometrium and these effects are enhanced by estradiol. The reduced interval between PGFM peaks that was observed in the estradiol-treated ewes was associated with an earlier onset of luteolysis which is consistent with the idea that the frequency of PGF$\\sb{2\\alpha}$ is an important component of its luteolytic action. About 50% of the oxytocin and PGFM peaks overlapped, suggesting that oxytocin is not the only factor controlling the pulsatile secretion of PGF$\\sb{2\\alpha}$. The oxytocin-independent PGF$\\sb{2\\alpha}$ pulses may be sensitive to the effects of estradiol.","abstract_html":"The objectives in this study were to evaluate the influence of withdrawal of progesterone on induction of the uterine oxytocin receptor in the absence and presence of estradiol and to determine whether or not estradiol of ovarian follicular origin is necessary for induction of the oxytocin receptor and the pulsatile secretion of prostaglandin F<span class=\"etd-inline-math\">\\sb{2&alpha;}</span> (PGF<span class=\"etd-inline-math\">\\sb{2&alpha;}</span>) during spontaneous luteolysis. Continuous treatment with progesterone for 9 or 12 days reduced the density of oxytocin receptors in endometrium and myometrium when compared to the vehicle-treated groups. In the endometrium, withdrawal of progesterone after day 9 resulted in an increase in the concentration of oxytocin receptor on day 13 (P $&lt;$ 0.01) and estradiol enhanced the effects of progesterone withdrawal (P $&lt;$ 0.01). Otherwise, the effect of estradiol was to reduce oxytocin receptor concentrations (P $&lt;$ 0.01). X-irradiation prolonged the luteal phase of the estrous cycle. Estradiol treatment reversed the effects of X-irradiation and shortened the estrous cycle when compared to the ewes which received sham X-irradiation and placebos. About 50 percent of PGFM peaks overlapped with oxytocin peaks and no difference in the percentage of overlapped PGFM peaks was observed between estradiol-treated ewes and the ewes receiving placebos. Estradiol treatment decreased the interval between PGFM peaks (P $&lt;$ 0.01) and increased the interval between oxytocin peaks (P $&lt;$ 0.01). Lower concentrations of oxytocin receptor in the endometrium (P $&lt;$ 0.01) but higher concentrations of oxytocin receptor in the myometrium (P $&lt;$ 0.01) were observed in estradiol-treated ewes when compared to the ewes treated with placebos. In conclusion, withdrawal of progesterone induces the formation of oxytocin receptor in endometrium and these effects are enhanced by estradiol. The reduced interval between PGFM peaks that was observed in the estradiol-treated ewes was associated with an earlier onset of luteolysis which is consistent with the idea that the frequency of PGF<span class=\"etd-inline-math\">\\sb{2&alpha;}</span> is an important component of its luteolytic action. About 50% of the oxytocin and PGFM peaks overlapped, suggesting that oxytocin is not the only factor controlling the pulsatile secretion of PGF<span class=\"etd-inline-math\">\\sb{2&alpha;}</span>. The oxytocin-independent PGF<span class=\"etd-inline-math\">\\sb{2&alpha;}</span> pulses may be sensitive to the effects of estradiol.","abstract_has_math":true,"creators":["Zhang, Jiahua"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Biology, Veterinary Science","degree_department":null,"school":null,"contributors":["Hixon, James E."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T14:20:38Z","date_published":"2011-05-07T14:20:38Z","updated_at":"2026-07-22T22:25:22Z","subjects":["Biology, Veterinary Science"],"languages":["eng"],"rights":["Copyright 1991 Zhang, Jiahua"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9124513","(UMI)AAI9124513"],"render_values":[{"text":"AAI9124513","href":null,"code":true},{"text":"(UMI)AAI9124513","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/23613","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Hixon, James E."]},{"key":"dc:creator","label":"Author","values":["Zhang, Jiahua"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T14:20:38Z","10000-01-01","1991"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Biology, Veterinary Science"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Biology, Veterinary Science"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1991 Zhang, Jiahua"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9124513","(UMI)AAI9124513","http://hdl.handle.net/2142/23613"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["The objectives in this study were to evaluate the influence of withdrawal of progesterone on induction of the uterine oxytocin receptor in the absence and presence of estradiol and to determine whether or not estradiol of ovarian follicular origin is necessary for induction of the oxytocin receptor and the pulsatile secretion of prostaglandin F$\\sb{2\\alpha}$ (PGF$\\sb{2\\alpha}$) during spontaneous luteolysis. Continuous treatment with progesterone for 9 or 12 days reduced the density of oxytocin receptors in endometrium and myometrium when compared to the vehicle-treated groups. In the endometrium, withdrawal of progesterone after day 9 resulted in an increase in the concentration of oxytocin receptor on day 13 (P $<$ 0.01) and estradiol enhanced the effects of progesterone withdrawal (P $<$ 0.01). Otherwise, the effect of estradiol was to reduce oxytocin receptor concentrations (P $<$ 0.01). X-irradiation prolonged the luteal phase of the estrous cycle. Estradiol treatment reversed the effects of X-irradiation and shortened the estrous cycle when compared to the ewes which received sham X-irradiation and placebos. About 50 percent of PGFM peaks overlapped with oxytocin peaks and no difference in the percentage of overlapped PGFM peaks was observed between estradiol-treated ewes and the ewes receiving placebos. Estradiol treatment decreased the interval between PGFM peaks (P $<$ 0.01) and increased the interval between oxytocin peaks (P $<$ 0.01). Lower concentrations of oxytocin receptor in the endometrium (P $<$ 0.01) but higher concentrations of oxytocin receptor in the myometrium (P $<$ 0.01) were observed in estradiol-treated ewes when compared to the ewes treated with placebos. In conclusion, withdrawal of progesterone induces the formation of oxytocin receptor in endometrium and these effects are enhanced by estradiol. The reduced interval between PGFM peaks that was observed in the estradiol-treated ewes was associated with an earlier onset of luteolysis which is consistent with the idea that the frequency of PGF$\\sb{2\\alpha}$ is an important component of its luteolytic action. About 50% of the oxytocin and PGFM peaks overlapped, suggesting that oxytocin is not the only factor controlling the pulsatile secretion of PGF$\\sb{2\\alpha}$. The oxytocin-independent PGF$\\sb{2\\alpha}$ pulses may be sensitive to the effects of estradiol.","Made available in DSpace on 2011-05-07T14:20:38Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9124513.pdf: 7411298 bytes, checksum: 8f7b33622663137e1fba9140769c4b8c (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:05:40Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:31:29-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"]},{"key":"dc:title","label":"Title","values":["Induction of the oxytocin receptor and its role in luteolysis in sheep"]}]}],"canonical_facts":{"dc:contributor":["Hixon, James E."],"dc:creator":["Zhang, Jiahua"],"dc:date":["2011-05-07T14:20:38Z","10000-01-01","1991"],"dc:description":["The objectives in this study were to evaluate the influence of withdrawal of progesterone on induction of the uterine oxytocin receptor in the absence and presence of estradiol and to determine whether or not estradiol of ovarian follicular origin is necessary for induction of the oxytocin receptor and the pulsatile secretion of prostaglandin F$\\sb{2\\alpha}$ (PGF$\\sb{2\\alpha}$) during spontaneous luteolysis. Continuous treatment with progesterone for 9 or 12 days reduced the density of oxytocin receptors in endometrium and myometrium when compared to the vehicle-treated groups. In the endometrium, withdrawal of progesterone after day 9 resulted in an increase in the concentration of oxytocin receptor on day 13 (P $<$ 0.01) and estradiol enhanced the effects of progesterone withdrawal (P $<$ 0.01). Otherwise, the effect of estradiol was to reduce oxytocin receptor concentrations (P $<$ 0.01). X-irradiation prolonged the luteal phase of the estrous cycle. Estradiol treatment reversed the effects of X-irradiation and shortened the estrous cycle when compared to the ewes which received sham X-irradiation and placebos. About 50 percent of PGFM peaks overlapped with oxytocin peaks and no difference in the percentage of overlapped PGFM peaks was observed between estradiol-treated ewes and the ewes receiving placebos. Estradiol treatment decreased the interval between PGFM peaks (P $<$ 0.01) and increased the interval between oxytocin peaks (P $<$ 0.01). Lower concentrations of oxytocin receptor in the endometrium (P $<$ 0.01) but higher concentrations of oxytocin receptor in the myometrium (P $<$ 0.01) were observed in estradiol-treated ewes when compared to the ewes treated with placebos. In conclusion, withdrawal of progesterone induces the formation of oxytocin receptor in endometrium and these effects are enhanced by estradiol. The reduced interval between PGFM peaks that was observed in the estradiol-treated ewes was associated with an earlier onset of luteolysis which is consistent with the idea that the frequency of PGF$\\sb{2\\alpha}$ is an important component of its luteolytic action. About 50% of the oxytocin and PGFM peaks overlapped, suggesting that oxytocin is not the only factor controlling the pulsatile secretion of PGF$\\sb{2\\alpha}$. The oxytocin-independent PGF$\\sb{2\\alpha}$ pulses may be sensitive to the effects of estradiol.","Made available in DSpace on 2011-05-07T14:20:38Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9124513.pdf: 7411298 bytes, checksum: 8f7b33622663137e1fba9140769c4b8c (MD5) Previous issue date: 1991","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:05:40Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:31:29-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission","U of I Only"],"dc:identifier":["AAI9124513","(UMI)AAI9124513","http://hdl.handle.net/2142/23613"],"dc:language":["eng"],"dc:rights":["Copyright 1991 Zhang, Jiahua"],"dc:subject":["Biology, Veterinary Science"],"dc:title":["Induction of the oxytocin receptor and its role in luteolysis in sheep"],"dc:type":["text"],"thesis:degree_discipline":["Biology, Veterinary Science"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:22Z"}