Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1981-3-24
pubmed:abstractText
The synthesis and purification of several analogues of the melanotropins with amino acid substitutions at the tyrosine-2 and methionine-4(7) positions are reported. The compounds synthesized included [4-norleucine]-alpha-MSH, [7-norleucine]-beta p-MSH, [2-3',5'-diiodotyrosine]-alpha-MSH, [2-D-tyrosine]-alpha-MSH, and [2-phenylalanine,4-norleucine]-alpha-MSH. The biological activities of these derivatives were measured and compared on normal melanocytes (frog skins) and on transformed melanocytes (mouse melanoma adenylate cyclase), over the entire dose-response range. All compounds tested were full agonists in both assay systems but varied considerably in potency. The relative potencies in the frog skin assay (alpha-MSH = 1.0) were as follows: [Nle7]-beta p-MSH (5.2) > [Nle4]-alpha-MSH (2.3) > alpha-MSH (1.0) > [Phe2,Nle4]-alpha-MSH (0.80) > beta p-MSH (0.55) > [I2-Tyr2]-alpha-MSH (0.12) > [D-Tyr2]-alpha-MSH (0.04). The relative potencies in the melanoma adenylate cyclase system were [Nle7]-beta p-MSH (4.2) > beta p-MSH (2.2) > [Nle4]-alpha-MSH (2.0) > alpha-MSH (1.0) approximately equal to [Phe2,Nle4]-alpha-MSH (0.9) > [I2-Tyr2]-alpha-MSH (0.40) > [D-Tyr2]-alpha-MSH (0.20). There appears to be some differences in structural specificity at the melanotropin receptors of the two cell systems.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0022-2623
pubmed:author
pubmed:issnType
Print
pubmed:volume
23
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1432-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1980
pubmed:articleTitle
Synthesis and structure-function studies of melanocyte stimulating hormone analogues modified in the 2 and 4(7) positions: comparison of activities on frog skin melanophores and melanoma adenylate cyclase.
pubmed:publicationType
Journal Article, Comparative Study, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.