G Protein-Coupled Receptor (GPCR)
Definition
G protein-coupled receptors (GPCRs) are the largest family of cell surface receptors, characterized by seven transmembrane domains and signal transduction through intracellular G proteins. Many peptide hormones and research peptides act through GPCRs — including GLP-1 receptor agonists (semaglutide, tirzepatide), melanocortin receptor agonists (PT-141, melanotan II), and growth hormone secretagogues (ipamorelin, GHRP-2, GHRP-6).
Related Terms
Related Compounds
Semaglutide
An in-depth review of Semaglutide, a long-acting GLP-1 receptor agonist, covering its mechanism of action, albumin-binding pharmacokinetics, and research applications in metabolic health, weight management, and cardiovascular outcomes.
Read monographTirzepatide
An in-depth review of Tirzepatide, the first dual GIP/GLP-1 receptor agonist ('twincretin'), examining its mechanism of action, superior glycemic and weight loss efficacy, and research applications in metabolic health.
Read monographPT-141
An in-depth review of PT-141 (Bremelanotide), a cyclic melanocortin receptor agonist, covering its mechanism of action, pharmacokinetics, research applications in sexual function, melanocortin pharmacology, CNS-mediated arousal pathways, safety profile, and dosing in research models.
Read monographIpamorelin
An in-depth review of Ipamorelin, a highly selective growth hormone secretagogue pentapeptide, covering its mechanism of action, pharmacokinetics, research applications in GH release, bone density, muscle growth, and safety profile.
Read monographRelated Studies
Tirzepatide Once Weekly for the Treatment of Obesity
Jastreboff AM, Aronne LJ, Ahmad NN, et al. · New England Journal of Medicine (2022)
Once-Weekly Semaglutide in Adults with Overweight or Obesity
Wilding JPH, Batterham RL, Calanna S, et al. · New England Journal of Medicine (2021)
Efficacy and Safety of Tirzepatide Monotherapy in Type 2 Diabetes (SURPASS-1)
Rosenstock J, Wysham C, Frias JP, et al. · New England Journal of Medicine (2021)
Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials (RECONNECT)
Kingsberg SA, Clayton AH, Portman D, et al. · Obstetrics and Gynecology (2019)