title: The natriuretic mechanism of Gamma-Melanocyte-Stimulating Hormone.
abstract: Gamma-Melanocyte Stimulating Hormone (Gamma-MSH) regulates sodium (Na(+)) balance and blood pressure through activation of the melanocortin receptor 3 (MC3-R). The mechanism of the natriuretic effect is proposed to involve binding of MC3-R either in the kidney to directly inhibit tubular Na(+) transport or in the brain to inhibit central neural pathways that control renal tubular Na(+) absorption. This study aimed to clarify the mechanism involved in the natriuretic effect of Gamma-MSH on MC3-R in kidney cells. In Ussing chamber studies, we observed no effects of Gamma-MSH on NaCl transport in the mouse inner medullary collecting duct cell line (mIMCD-K2). We also found that neither MC3-R protein nor mRNA was expressed in mouse kidney, suggesting that renal Gamma-MSH action may not be mediated through direct effects on tubular Na(+) transport but rather through effects on central neural pathways that innervate the kidney.
authors.affiliation: Department of Medicine, Division of Nephrology, Stanford University, Stanford, CA 94305, United States.
authors.forename: Paru P
authors.initials: PP
authors.lastname: Kathpalia
authors.forename: Carol
authors.initials: C
authors.lastname: Charlton
authors.forename: Madhumitha
authors.initials: M
authors.lastname: Rajagopal
authors.forename: Alan C
authors.initials: AC
authors.lastname: Pao
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D015153:Blotting, Western; D002460:Cell Line; D000242:Cyclic AMP / Q000378:metabolism; D007150:Immunohistochemistry; D007685:Kidney Tubules, Collecting / Q000166:cytology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D044104:Receptor, Melanocortin, Type 3 / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction / Q000187:drug effects; D012964:Sodium / Q000378:metabolism; D019825:gamma-MSH / Q000494:pharmacology*
chemical_list: D044104:Receptor, Melanocortin, Type 3; D019825:gamma-MSH; D012964:Sodium; D000242:Cyclic AMP