title: Melanotropin potentiating factor inhibits lipolytic activity of beta-lipotropin but not of melanocyte stimulating hormones.
abstract: Melanotropin potentiating factor (MPF) potentiates the melanotropic activity of melanocyte stimulating hormones. Although the message sequence for the melanotropic and lipolytic activity are identical for beta-lipotropin, alpha- and beta-MSH, MPF was not able to affect the lipolytic response to alpha- and beta-MSH in rabbit adipocytes. However, MPF at concentrations of 10-5 and 10-6 mol/l inhibited the lipolytic activity of beta-lipotropin. This suggests that the inhibition of the lipolytic response to beta-lipotropin is not connected with the common lipolytic message sequence (beta-LPH 47-53). Since beta-lipotropin has a second lipolytic sequence in its C-terminal part this second lipolytic core of beta-lipotropin might interact with MPF which has no intrinsic lipolytic activity.
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D004151:Dipeptides / Q000494:pharmacology*; D004347:Drug Interactions; D004723:Endorphins; D005990:Glycerol / Q000378:metabolism; D008066:Lipolysis / Q000187:drug effects*; D009074:Melanocyte-Stimulating Hormones / Q000494:pharmacology*; D010446:Peptide Fragments; D011817:Rabbits; D008083:beta-Lipotropin / Q000037:antagonists & inhibitors*
chemical_list: D004151:Dipeptides; D004723:Endorphins; D010446:Peptide Fragments; C050079:lysyl-lysyl-glycyl-glutamic acid; D009074:Melanocyte-Stimulating Hormones; D008083:beta-Lipotropin; D005990:Glycerol