Related Experiment Video
Updated: Jun 9, 2026

Using Chronic Social Stress to Model Postpartum Depression in Lactating Rodents
Published on: June 10, 2013
Progesterone reduces the inhibitory effect of a serotonin 1B receptor agonist on lordosis behavior
Lynda Uphouse1, Jutatip Guptarak, Cindy Hiegel
1Department of Biology, Texas Woman's University, Denton, TX 76204, United States. LUphouse@mail.twu.edu
Abstract:
Ovariectomized Fischer inbred rats were hormonally primed with 10μg estradiol benzoate and sesame seed oil (EO rats) or with estradiol benzoate and 500μg progesterone (EP rats). Four to six hours after progesterone or oil, rats were pretested for sexual behavior and then infused bilaterally into the ventromedial nucleus of the hypothalamus with 0, 50, 100 or 200ng of the 5-HT(1B) receptor agonist, 1,4-dihydro-3-(1,2,3,6-tetrahydro-4-pyridinyl)-5H-pyrrol[3,2-bi]pyridin-5-one-dihydrochloride (CP 93129). Sexual receptivity was monitored by the lordosis to mount (L/M) ratio. EO rats showed a transient decline in lordosis behavior following infusion with the saline vehicle and this was amplified by CP 93129. There were no effects of any infusion in EP rats. These findings are discussed in terms of the possible stress effect of the intracranial infusion in EO rats and their implications for a role of 5-HT(1B) receptors in the response to a mild stress.
Related Concept Videos
Drugs Affecting GI Tract Motility: Serotonin Receptor Agonists
G-protein Coupled Receptors
Drugs Affecting Neurotransmitter Release or Uptake
Antidepressant Drugs: MAOIs and Other Agents
Drugs Affecting GI Tract Motility: Dopamine Receptor Antagonists
Hormonal Regulation of the Menstrual Cycle
At puberty, GnRH begins a pulsatile release pattern, which triggers the anterior pituitary gland to secrete follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The frequency and amplitude of GnRH pulses vary across the menstrual cycle, with faster pulses favoring LH release and slower pulses favoring FSH release.