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The ovary-mediated FSH attenuation of the LH surge in the rat involves a decreased gonadotroph progesterone receptor (PR) action but not PR expression.
J Endocrinol. 2008 Mar; 196(3):583-92.JE

Abstract

Hyperstimulation of ovarian function with human FSH (hFSH) attenuates the preovulatory surge of LH. These experiments aimed at investigating the mechanism of ovarian-mediated FSH suppression of the progesterone (P(4)) receptor (PR)-dependent LH surge in the rat. Four-day cycling rats were injected with hFSH, oestradiol benzoate (EB) or vehicle during the dioestrous phase. On pro-oestrus, their pituitaries were studied for PR mRNA and protein expression. Additionally, pro-oestrous pituitaries were incubated in the presence of oestradiol-17beta (E(2)), and primed with P(4) and LH-releasing hormone (LHRH), with or without the antiprogestin RU486. After 1 h of incubation, pituitaries were either challenged or not challenged with LHRH. Measured basal and LHRH-stimulated LH secretions and LHRH self-priming were compared with those exhibited by incubated pituitaries on day 4 from ovariectomized (OVX) rats in metoestrus (day 2) injected with hFSH and/or EB on days 2 and 3. The results showed that: i) hFSH lowered the spontaneous LH surge without affecting basal LH and E(2) levels, gonadotroph PR-A/PR-B mRNA ratio or immunohistochemical protein expression; ii) incubated pro-oestrous pituitaries from hFSH-treated rats did not respond to P(4) or LHRH, and lacked E(2)-augmenting and LHRH self-priming effects and iii) OVX reversed the inhibitory effects of hFSH on LH secretion. It is concluded that under the influence of hFSH, the ovaries produce a non-steroidal factor which suppresses all PR-dependent events of the LH surge elicited by E(2). The action of such a factor seemed to be due to a blockade of gonadotroph PR action rather than to an inhibition of PR expression.

Authors+Show Affiliations

Departments of Cell Biology, Physiology and Immunology and Comparative Pathology, University of Córdoba, 14004 Córdoba, Spain IVI Madrid, Madrid, Spain.No affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

18310454

Citation

Gordon, Ana, et al. "The Ovary-mediated FSH Attenuation of the LH Surge in the Rat Involves a Decreased Gonadotroph Progesterone Receptor (PR) Action but Not PR Expression." The Journal of Endocrinology, vol. 196, no. 3, 2008, pp. 583-92.
Gordon A, Garrido-Gracia JC, Aguilar R, et al. The ovary-mediated FSH attenuation of the LH surge in the rat involves a decreased gonadotroph progesterone receptor (PR) action but not PR expression. J Endocrinol. 2008;196(3):583-92.
Gordon, A., Garrido-Gracia, J. C., Aguilar, R., Bellido, C., Velasco, J. A., Millan, Y., Tena-Sempere, M., Martín de Las Mulas, J., & Sánchez-Criado, J. E. (2008). The ovary-mediated FSH attenuation of the LH surge in the rat involves a decreased gonadotroph progesterone receptor (PR) action but not PR expression. The Journal of Endocrinology, 196(3), 583-92. https://doi.org/10.1677/JOE-07-0223
Gordon A, et al. The Ovary-mediated FSH Attenuation of the LH Surge in the Rat Involves a Decreased Gonadotroph Progesterone Receptor (PR) Action but Not PR Expression. J Endocrinol. 2008;196(3):583-92. PubMed PMID: 18310454.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - The ovary-mediated FSH attenuation of the LH surge in the rat involves a decreased gonadotroph progesterone receptor (PR) action but not PR expression. AU - Gordon,Ana, AU - Garrido-Gracia,José C, AU - Aguilar,Rafaela, AU - Bellido,Carmina, AU - Velasco,Juan A García, AU - Millan,Yolanda, AU - Tena-Sempere,Manuel, AU - Martín de Las Mulas,Juana, AU - Sánchez-Criado,José E, PY - 2008/3/4/pubmed PY - 2009/10/2/medline PY - 2008/3/4/entrez SP - 583 EP - 92 JF - The Journal of endocrinology JO - J Endocrinol VL - 196 IS - 3 N2 - Hyperstimulation of ovarian function with human FSH (hFSH) attenuates the preovulatory surge of LH. These experiments aimed at investigating the mechanism of ovarian-mediated FSH suppression of the progesterone (P(4)) receptor (PR)-dependent LH surge in the rat. Four-day cycling rats were injected with hFSH, oestradiol benzoate (EB) or vehicle during the dioestrous phase. On pro-oestrus, their pituitaries were studied for PR mRNA and protein expression. Additionally, pro-oestrous pituitaries were incubated in the presence of oestradiol-17beta (E(2)), and primed with P(4) and LH-releasing hormone (LHRH), with or without the antiprogestin RU486. After 1 h of incubation, pituitaries were either challenged or not challenged with LHRH. Measured basal and LHRH-stimulated LH secretions and LHRH self-priming were compared with those exhibited by incubated pituitaries on day 4 from ovariectomized (OVX) rats in metoestrus (day 2) injected with hFSH and/or EB on days 2 and 3. The results showed that: i) hFSH lowered the spontaneous LH surge without affecting basal LH and E(2) levels, gonadotroph PR-A/PR-B mRNA ratio or immunohistochemical protein expression; ii) incubated pro-oestrous pituitaries from hFSH-treated rats did not respond to P(4) or LHRH, and lacked E(2)-augmenting and LHRH self-priming effects and iii) OVX reversed the inhibitory effects of hFSH on LH secretion. It is concluded that under the influence of hFSH, the ovaries produce a non-steroidal factor which suppresses all PR-dependent events of the LH surge elicited by E(2). The action of such a factor seemed to be due to a blockade of gonadotroph PR action rather than to an inhibition of PR expression. SN - 1479-6805 UR - https://www.unboundmedicine.com/medline/citation/18310454/The_ovary_mediated_FSH_attenuation_of_the_LH_surge_in_the_rat_involves_a_decreased_gonadotroph_progesterone_receptor__PR__action_but_not_PR_expression_ L2 - https://joe.bioscientifica.com/doi/10.1677/JOE-07-0223 DB - PRIME DP - Unbound Medicine ER -