What is the molecular size of PT-141 (bremelanotide)?

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From the Research

PT-141 (bremelanotide) has a molecular weight of 1025.2 g/mol (or 1025.2 daltons). This synthetic peptide consists of seven amino acids in a specific sequence, making it a relatively small peptide molecule. Its compact molecular size allows it to cross the blood-brain barrier effectively, which is important for its mechanism of action as a melanocortin receptor agonist. The molecular formula for bremelanotide is C50H68N14O10, reflecting its composition of carbon, hydrogen, nitrogen, and oxygen atoms. This molecular size is significant for its pharmacokinetic properties, including how it's absorbed, distributed throughout the body, and eventually metabolized. The peptide's size also influences its half-life in the body, which is approximately 2.7 hours, and contributes to its ability to bind to melanocortin-4 receptors in the central nervous system, where it exerts its therapeutic effects for treating hypoactive sexual desire disorder in premenopausal women 1.

Some key points to consider about PT-141 (bremelanotide) include:

  • Its molecular size and structure allow for effective crossing of the blood-brain barrier
  • It is a melanocortin receptor agonist, specifically targeting MC3R and MC4R receptors
  • Its pharmacokinetic properties, including absorption, distribution, and metabolism, are influenced by its molecular size
  • The peptide's size and half-life contribute to its ability to bind to melanocortin-4 receptors in the central nervous system
  • Bremelanotide has been shown to increase sexual desire and arousal in women with hypoactive sexual desire disorder, as demonstrated in clinical trials 2, 3, 4.

Overall, the molecular size of PT-141 (bremelanotide) is a critical factor in its mechanism of action and therapeutic effects, and its unique properties make it a promising treatment option for hypoactive sexual desire disorder in premenopausal women 5.

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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