Ac-[Nle4, D-Phe7]-α-MSH4-9-NH2 and Ac-[Nle4]-α-MSH4-9-NH2, fragment analogs of the tridecapeptide, α-melanocyte stimulating hormone (α-MSH, α-melanotropin), were synthesized. The potency and prolonged activity of the analogs were compared to α-MSH in several melanotropin bioassays. The D-Phe-containing hexapeptide was 10 times more active than α-MSH in stimulating melanoma tyrosinase activity. This analog was also 10-fold more potent than α-MSH in the lizard skin bioassay and about 10-fold less active in the frog skin bioassay. The melanotropic activity of Ac-[Nle4, D-Phe7]-α-MSH4-9-NH2 was considerably prolonged compared to α-MSH in each of the bioassays. These results demonstrate that the structural requirements for superpotency and prolonged activity of [Nle4, D-Phe7]-substituted analogs reside within this hexapeptide sequence.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Jun 13 1986|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology