Related Experiment Video
Updated: Dec 26, 2025

Author Spotlight: Hypothalamic Neural Mechanism Insights
Published on: August 4, 2023
Neuropeptides responding to leptin
1Department of Nutritional Sciences, University of California, Berkeley 94720-3104, USA.
Abstract:
Leptin, the circulating protein that inhibits food intake and energy expenditure, was thought to function through inhibition of the hypothalamic neuropeptide Y (NPY), a stimulator of food intake. However, mouse mutants lacking NPY are normal, suggesting that alternative neuromodulators of food intake must exist. Recently, melanocortin, a neuropeptide acting on the hypothalamic receptor melanocortin4-R, was discovered in mice, controlling energy regulation. This receptor is antagonized by the "agouti" protein in the mutant obese agouti mouse.
Related Concept Videos
Regulation of Food Intake
Transducer Mechanism: Enzyme-Linked Receptors
Major types that are helpful drug targets include:
Hormonal Regulation
Target Cell Response to Hormones
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Spare Receptors
Insulin: The Receptor and Signaling Pathways

