Relative stability of α-melanotropin and related analogues to rat brain homogenates

Kazufumi Akiyama, Henry I. Yamamura, Brian C. Wilkes, Wayne L. Cody, Victor J. Hruby, Ana Maria de L. Castrucci, Mac E. Hadley

Research output: Contribution to journalArticlepeer-review

14 Scopus citations


α-Melanotropin (α-MSH) retains less than 1% of its original activity after a 60 min incubation with 10% rat brain homogenate. [Nle4, D-Phe7]-α-MSH is nonbiodegradable in rat serum (240 min incubation) and still maintains 10% of its original activity in 10% rat brain homogenate (240 min incubation). The related fragment analogue, Ac-[Nle4, D-Phe7]-α-MSH4-10-NH2, retains 50% of its activity after a 240 min incubation in rat brain homogenate, whereas Ac-[Nle4, D-Phe7]-α-MSH4-11-NH2 is totally resistant to inactivation by rat brain homogenate. Both [Nle4, D-Phe7]-fragments are resistant to degradation by rat serum, but [Nle4]-α-MSH, Ac-[Nle4]-α-MSH4-10-NH2 and Ac-[Nle4]-α-MSH4-11-NH2 are rapidly inactivated under both conditions. The cyclic melanotropin, [Cys4,Cys10]-α-MSH, is inactivated in rat brain homogenate as is the shorter Ac-[Cys4,Cys10]-α-MSH4-10-NH2 analogue, but neither cyclic melanotropin is inactivated upon incubation in serum from rats. Ac-[Cys4,D-Phe7,Cys10]-α-MSH4-10-NH2 is resistant to inactivation by either rat serum or a brain homogenate. Some of these melanotropin analogues may provide useful probes for the localization and characterization of putative melanotropin receptors in both the central nervous system and peripheral tissues.

Original languageEnglish (US)
Pages (from-to)1191-1195
Number of pages5
Issue number6
StatePublished - 1984
Externally publishedYes


  • Brain
  • Hormone stability
  • Melanocyctes
  • Melanocyte stimulating hormone
  • Melanotropins
  • α-MSH

ASJC Scopus subject areas

  • Biochemistry
  • Physiology
  • Endocrinology
  • Cellular and Molecular Neuroscience


Dive into the research topics of 'Relative stability of α-melanotropin and related analogues to rat brain homogenates'. Together they form a unique fingerprint.

Cite this