Calcitonin receptor-stimulating peptide-1 regulates ion transport and growth of renal epithelial cell line LLC-PK1.
Calcitonin receptor-stimulating peptide-1 (CRSP-1) is a peptide recently identified from porcine brain by monitoring the cAMP production through an endogenous calcitonin (CT) receptor in the renal epithelial cell line LLC-PK(1). Here we investigated the effects of CRSP-1 on the ion transport and growth of LLC-PK(1) cells. CRSP-1 inhibited the growth of LLC-PK(1) cells with a higher potency than porcine CT. CRSP-1 enhanced the uptake of (22)Na(+) into LLC-PK(1) cells more strongly than did CT and slightly reduced the (45)Ca(2+) uptake. The enhancement of the (22)Na(+) uptake was abolished by 5-(N-ethyl-N-isopropyl) amiloride, a strong Na(+)/H(+) exchanger (NHE) inhibitor for NHE1, even at a concentration of 1x10(-8)M, although other ion transporter inhibitors did not affect the (22)Na(+) uptake. These results indicate that CRSP-1 enhances the (22)Na(+) uptake by the specific activation of NHE1. Taken together, CRSP-1 is considered to be a new regulator for the urinary ion excretion and renal epithelial cell growth.
Hamano
Kazumasa
K
National Cardiovascular Center Research Institute, 5-7-1 Fujishirodai, Suita, Osaka 565-8565, Japan.
Katafuchi
Takeshi
T
Kikumoto
Katsuro
K
Minamino
Naoto
N
D000818:Animals; D004847:Epithelial Cells / Q000378:metabolism; D017136:Ion Transport; D007668:Kidney / Q000166:cytology / Q000378:metabolism*; D018374:LLC-PK1 Cells; D010455:Peptides / Q000494:pharmacology*; D018003:Receptors, Calcitonin / Q000819:agonists*; D013552:Swine
D010455:Peptides; D018003:Receptors, Calcitonin