TY - JOUR
T1 - Melanocyte stimulating hormone and melanin concentrating hormone may be structurally and evolutionarily related
AU - Castrucci, Ana Maria de L.
AU - Hadley, Mac E.
AU - Lebl, Michal
AU - Zechel, Christian
AU - Hruby, Victor J.
N1 - Funding Information:
These studies were partially supported by the Fundacao de Amparo a Pesquisa do Estado de Sa, o Pauio, Grants 84/1967 and 85/0718-7 (Brasil), U.S. Public Health Service grant AM-17420, and National Science Foundation grant DCB-8615706.
PY - 1989/1
Y1 - 1989/1
N2 - Two melanotropic peptides, melanin concentrating hormone (MCH) and α-melanocyte stimulating hormone (α-MSH), exert opposing actions on melanosome (melanin granule) movements within teleost pigment cells, melanocytes (melanophores). MCH stimulates melanosome aggregation to the cell center whereas α-MSH stimulates pigment organelle dispersion out into the dendritic processes of the melanocytes. The actions of α-MSH are dependent upon extracellular calcium (Ca2+), whereas those of MCH are actually enhanced in the absence of the cation. At high concentrations (10-5-10-8 M) MCH also exhibits MSH-like activity (autoantagonism), an effect which is abolished in the absence of Ca2+. Therefore, MCH exhibits MCH-like as well as MSH-like activity depending on the presence or absence of extracellular Ca2+. An analogue of MCH, [Ala5, Cys10]MCH, has been synthesized which is totally devoid of MCH activity but still exhibits MSH-like activity. These results suggest that the two melanotropic peptides share some component of structural similarity and may be evolutionarily related.
AB - Two melanotropic peptides, melanin concentrating hormone (MCH) and α-melanocyte stimulating hormone (α-MSH), exert opposing actions on melanosome (melanin granule) movements within teleost pigment cells, melanocytes (melanophores). MCH stimulates melanosome aggregation to the cell center whereas α-MSH stimulates pigment organelle dispersion out into the dendritic processes of the melanocytes. The actions of α-MSH are dependent upon extracellular calcium (Ca2+), whereas those of MCH are actually enhanced in the absence of the cation. At high concentrations (10-5-10-8 M) MCH also exhibits MSH-like activity (autoantagonism), an effect which is abolished in the absence of Ca2+. Therefore, MCH exhibits MCH-like as well as MSH-like activity depending on the presence or absence of extracellular Ca2+. An analogue of MCH, [Ala5, Cys10]MCH, has been synthesized which is totally devoid of MCH activity but still exhibits MSH-like activity. These results suggest that the two melanotropic peptides share some component of structural similarity and may be evolutionarily related.
KW - Melanosome
KW - Melanotropic peptide
KW - Melanotropin
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U2 - 10.1016/0167-0115(89)90208-5
DO - 10.1016/0167-0115(89)90208-5
M3 - Article
C2 - 2544929
AN - SCOPUS:0024533847
SN - 0167-0115
VL - 24
SP - 27
EP - 35
JO - Regulatory Peptides
JF - Regulatory Peptides
IS - 1
ER -