Abstract
AspThrMetArgCysMetValGlyArgValTyrArgProCysTrpGluVal (melanin concentrating hormone, MCH) and several fragment analogs (MCH1-14, MCH5-17, MCH5-14) were synthesized and their biological activities determined in a very sensitive fish skin bioassay. The potency ranking and minimum effective doses of the peptides were determined to be: MCH1-17 (10-12M) >< MCH5-17 (10-12M) > MCH1-14 (10-11M) > MCH5-14 (2 × 10-10M). The melanosome aggregating activity of MCH could be completely reversed by a 100-fold higher concentration of ≺-MSH. MCH was self-antagonized in a dose-related manner by higher concentrations of the peptide as was the activity of the MCH1-14 fragment analog. The MCH activities of the MCH5-17 and MCH5-14 analogs were not compromised by even the highest concentrations of the peptides employed. The MSH-like activity of MCH appears to relate to the N-terminus of the peptide whereas MCH activity is more a function of the C-terminus of the hormone. Self- antagonism of MCH at high concentrations appears to relate to the N-terminal tetrapeptide, which is responsible for the intrinsic MSH-like activity of the hormone.
Original language | English (US) |
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Pages (from-to) | 1845-1851 |
Number of pages | 7 |
Journal | Life Sciences |
Volume | 40 |
Issue number | 19 |
DOIs | |
State | Published - May 11 1987 |
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- Pharmacology, Toxicology and Pharmaceutics(all)