title: [Detection of binding activity and biologic effect of a novel alpha-melanocyte-stimulating hormone analogue].
abstract: Binding activity and biologic effect of a novel alpha-melanocyte-stimulating hormone analogue were tested on cells transiently expressing the human melanocortin-1 (MC1), MC3, MC4, and MC5 receptors. The human MC1 and MC5 receptor genes were cloned into the expression vector pcDNA3. 1/ myc-his(-) B. The vectors were transferred to HEK-293 cells by the calcium phosphate method. Stable receptor populations were generated using G418 selection (900 microg x mL(-1)) for subsequent bioassay analysis. K(i) values of the novel alpha-MSH analogue for MC1, MC3, MC4, and MC5 receptors were obtained in competition with [125I]-NDP-MSH for binding studies. The cyclic AMP level was tested by using [3H]-cyclic AMP kit. It is showed that K(i) values of the novel alpha-MSH analogue for MC1, MC3, MC4, and MC5 receptors were (0.159 +/- 0.040), (35.430 +/- 6.743), (19.293 +/- 2.780) and (2.230 +/- 0.670) nmol L(-1), respectively. Its EC50 values for MC1, MC3, MC4, and MC5 receptors were (0.45 +/- 0.07), (7.80 +/- 0.65), (2.55 +/- 0.23) and (0.33 +/- 0.09) nmol L(-1), respectively. In these tests, the novel alpha-MSH analogue is a MC1R and MC5R selective agonist.
authors.affiliation: Department of Laboratory Examination, Fuzhou General Hospital, Nanjing Military Command, Fuzhou 350025, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Ying
authors.forename: Xiao-Peng
authors.initials: XP
authors.lastname: Lan
authors.forename: Ye-Ping
authors.initials: YP
authors.lastname: Tian
mesh_terms: D000595:Amino Acid Sequence; D001667:Binding, Competitive; D002460:Cell Line; D045744:Cell Line, Tumor; D000242:Cyclic AMP / Q000378:metabolism; D005822:Genetic Vectors; D006801:Humans; D007457:Iodine Radioisotopes; D007700:Kinetics; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics; D011869:Radioligand Assay; D044102:Receptor, Melanocortin, Type 1 / Q000819:agonists / Q000235:genetics / Q000378:metabolism; D018043:Receptors, Corticotropin / Q000819:agonists / Q000235:genetics / Q000378:metabolism; D044101:Receptors, Melanocortin / Q000819:agonists / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D014316:Tritium; D000521:alpha-MSH / Q000031:analogs & derivatives / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D007457:Iodine Radioisotopes; D044102:Receptor, Melanocortin, Type 1; D018043:Receptors, Corticotropin; D044101:Receptors, Melanocortin; C086971:melanocortin 5 receptor; D014316:Tritium; D000521:alpha-MSH; D000242:Cyclic AMP