Related Experiment Video
Updated: Aug 16, 2026

Remote Neuronal Activation Coupled with Automated Blood Sampling to Induce and Measure Circulating Luteinizing Hormone in Mice
Published on: August 25, 2023
The serotonin type 3A receptor facilitates luteinizing hormone release and LHbeta promoter activity in immortalized
Phillip L Quirk1, Ruth E Siegel
1Medical Sciences Program, Indiana Universtiy, Bloomington, IN, USA.
Abstract:
The 5-hydroxytryptamine type 3A receptor (5-HT3AR) is a ligand-gated cation channel activated by serotonin. This receptor is expressed throughout the nervous system as well as in the pituitary gland. Although it has been documented that the 5-HT3AR modulates exocytosis in neurons, its role in the pituitary gland has not been determined. Previous research has shown that the 5-HT3AR modulates circulating gonadotropin levels in vivo. It is unclear, however, if its activation in the pituitary gland mediates these effects or if receptors elsewhere in the hypothalamus-pituitary-gondal axis are responsible. To investigate the potential for the 5-HT3AR to modulate gonadotropin release from pituitary gonadotropes, the gonadotrope-derived LbetaT2 cell line was used as a model system and radioimmunoassays were employed to investigate how 5-HT3AR activation influences luteinizing hormone (LH) release. Our studies demonstrate that gonadotropin releasing hormone (GnRH)-stimulated LH release was decreased by the 5-HT3AR-specific antagonist MDL 72222 in a concentration-dependent manner. In addition, it was found that overexpressing the 5-HT3AR in LbetaT2 cells enhanced both basal and GnRH-stimulated LH release and also increased LHbeta gene promoter activity. These results suggest that the 5-HT3AR may participate in the hypothalamus-pituitary-gonadal axis at the level of the pituitary gonadotrope to mediate pituitary hormone release.
Related Concept Videos
Hormones of the Pituitary Gland
The most abundantly secreted hormone from the anterior lobe is the growth hormone, which controls overall growth by...
Feedback Regulation of Calcium Concentration
Various transmembrane receptors, such as G protein-coupled receptors (GPCRs), elicit a response to extracellular signals by increasing cytosolic calcium. Activated GPCRs...
Testosterone: Functions and Regulation
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.
Regulation of Hormone Secretion
Humoral stimuli,...
G-protein Coupled Receptors
