Tibolone facilitates lordosis behavior through estrogen, progestin, and GnRH-1 receptors in estrogen-primed rats.

Abstract

A dose-response study was made of the broad-spectrum gonadal steroid agonist tibolone (TBL) on lordosis behavior in estradiol benzoate (EB: 5 µg) primed rats. Doses of TBL (0, 1, 4, and 16 μg) were infused to the right lateral ventricle 2 h before testing. The highest dose increased lordosis quotients significantly at 240 min and 360 min following infusion. However, the intensity of lordosis was weak. In experiment 2, the TBL dose of 16 µg was selected to determine whether tamoxifen (TMX), RU486, or antide could modify the lordosis response to TBL. Infusions of the three compounds, before TBL, significantly attenuated the TBL-induced facilitation of lordosis. The results suggest that TBL stimulates lordosis by activating estrogen, progesterone, and may do so by downstream stimulation of GnRH release. The physiological role TBL plays in controlling lordosis behavior remains to be determined.

• Authors: Marcos García-Juárez, Omar Montes-Narváez, Francisco Javier Lima-Hernández, Raymundo Domínguez-Ordoñez, James G Pfaus, Oscar González-Flores
• Journal: Neuroscience letters (Neurosci Lett) Vol. 736 Pg. 135299 (09 25 2020) ISSN: 1872-7972 [Electronic] Ireland
• PMID: 32777349 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2020. Published by Elsevier B.V.

Chemical References

• Estrogen Receptor Modulators
• Hormone Antagonists
• Norpregnenes
• Oligopeptides
• Receptors, Estrogen
• Receptors, LHRH
• Receptors, Progesterone
• estradiol 3-benzoate
• Mifepristone
• Estradiol
• iturelix
• tibolone

Topics

• Animals
• Estradiol (analogs & derivatives, pharmacology)
• Estrogen Receptor Modulators (pharmacology)
• Female
• Hormone Antagonists (pharmacology)
• Mifepristone (pharmacology)
• Norpregnenes (pharmacology)
• Oligopeptides (pharmacology)
• Posture
• Rats
• Rats, Sprague-Dawley
• Receptors, Estrogen (antagonists & inhibitors)
• Receptors, LHRH (antagonists & inhibitors)
• Receptors, Progesterone (antagonists & inhibitors)
• Sexual Behavior, Animal (drug effects)