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PT-141: a melanocortin agonist for the treatment of sexual dysfunction

P B Molinoff1, A M Shadiack, D Earle

  • 1Palatin Technologies, Inc, Cranbury, New Jersey 08512, USA.

Annals of the New York Academy of Sciences
|July 10, 2003
PubMed

Insights

PT-141, a synthetic peptide, activates melanocortin receptors in the brain to promote erectile function. Clinical studies show PT-141 rapidly increases erectile activity in men, suggesting its potential for treating sexual dysfunction.

Area of Science:

  • Neuroendocrinology
  • Pharmacology
  • Sexual Medicine

Background:

  • PT-141 is a synthetic peptide analog of alpha-melanocyte-stimulating hormone (α-MSH).
  • It acts as an agonist at melanocortin receptors (MC3R and MC4R), primarily located in the central nervous system.

Purpose of the Study:

  • To investigate the mechanism of action of PT-141 in inducing penile erections.
  • To evaluate the efficacy of PT-141 in treating erectile dysfunction.

Main Methods:

  • Administration of PT-141 to rats and nonhuman primates to observe physiological responses.
  • Assessment of neuronal activation in the hypothalamus using c-Fos immunoreactivity in rats.
  • Tracing neural pathways from the penis to the central nervous system using pseudorabies virus.
  • Clinical trials involving normal men and men with erectile dysfunction to assess erectile activity.

Main Results:

  • PT-141 administration induced penile erections in rats and nonhuman primates.
  • Systemic PT-141 activated hypothalamic neurons, indicated by increased c-Fos expression.
  • A rapid, dose-dependent increase in erectile activity was observed in human participants.
  • Neural pathways involved in erectile function were identified.

Conclusions:

  • PT-141 effectively stimulates erectile activity through central melanocortin receptor pathways.
  • The findings support PT-141's potential as a novel therapeutic agent for sexual dysfunction, particularly erectile dysfunction.

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