Related Experiment Video
Updated: Aug 17, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Melanocortinergic control of penile erection
H Wessells1, J E Blevins, T W Vanderah
1Department of Urology, University of Washington, Harborview Medical Center, 325 Ninth Avenue, Seattle, WA 98104, USA. wessells@u.washington.edu
Abstract:
Melanocortin receptors in the forebrain and spinal cord can be activated by endogenous or synthetic ligands to induce penile erection in rats and human subjects. To better understand how melanocortin circuits play a role in sex behavior, we review the contribution of melanocortin receptors and/or neurons in the hypothalamus, hindbrain, spinal cord and peripheral nerves to erectile function. New information regarding neuropeptides that mediate penile erection has extended our understanding of the central control of sex behavior, and melanocortin agonists may provide alternatives to existing treatment for highly prevalent problems including erectile dysfunction.
Related Concept Videos
Male Sexual Response: Erection & Ejaculation
The blood filling the erectile tissues compresses the veins, which helps to prevent blood from leaving...
Nitric Oxide Signaling Pathway
Direct-Acting Cholinergic Agonists: Pharmacological Actions
Drugs Acting on Autonomic Ganglia: Blockers
Smooth Muscle Contraction
The onset of contraction is triggered by an increase in calcium ions within the sarcoplasm, similar to the process in striated muscle. However, smooth muscles have a relatively smaller reservoir of the sarcoplasmic...
Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...