A decrease in the number or sensitivity of cell receptors in response to prolonged stimulation. Can reduce a peptide's effectiveness over time and is a reason many protocols include off-cycles.
"Downregulation" is filed under Pharmacology in the PeptideAtlas glossary, alongside 29 other terms in that group.
The term applies directly to 7 compound profiles here: Leuprolide (evidence A), Goserelin (evidence A), Triptorelin (evidence A), Nafarelin (evidence A), Histrelin (evidence A), Buserelin (evidence A), Apelin (evidence D). Each profile states the strength of the human evidence rather than only what the compound is claimed to do.
The proportion of a substance that enters the circulation when introduced into the body and is able to have an active effect. Different administration routes affect bioavailability.
The time required for the concentration of a substance in the body to decrease by half. Determines dosing frequency and accumulation patterns.
The study of how a drug moves through the body — absorption, distribution, metabolism, and excretion (ADME).
Compounds where this applies: Leuprolide, Goserelin, Triptorelin, Nafarelin, Histrelin, Buserelin, Apelin.
More Pharmacology terms: Bioavailability, Half-Life, Pharmacokinetics, Pharmacodynamics, First-Pass Metabolism, Receptor Agonist, Receptor Antagonist, Desensitization, Tachyphylaxis, GLP-1 (Glucagon-Like Peptide-1), GIP (Glucose-Dependent Insulinotropic Polypeptide), Glucagon, Amylin, Ghrelin, Growth Hormone Secretagogue (GHS), GHRP (Growth Hormone Releasing Peptide), GHRH (Growth Hormone Releasing Hormone), GHS-R1a (Growth Hormone Secretagogue Receptor), Secretagogue, Melanocortin Receptor.