Vasopressin elevates cytosolic calcium in small cell lung cancer cells.
The ability of vasopressin to elevate cytosolic Ca2+ in small cell lung cancer (SCLC) cells was investigated. Ten nanomolar vasopressin elevated the cytosolic Ca2+ in 6 of 8 SCLC cell lines that were loaded with Fura-2 AM. Using SCLC cell line NCI-H345, the effect of vasopressin was dose dependent, being maximal at 100 nM, where the cytosolic Ca2+ was elevated from 150 to 210 nM. Because addition of 1 mM EGTA had no effect on the vasopressin response, vasopressin released Ca2+ from intracellular pools. Also, oxytocin weakly elevated the cytosolic Ca2+. The response to vasopressin was strongly blocked by [(beta-mercapto-beta,beta-cyclopentamethylene propionic acid)1,O-MeTyr2,Arg8]vasopressin and weakly blocked by [(beta-mercapto-beta,beta-cyclopentamethylene propionic acid)1,O-MeTyr2,Orn8]vasotocin. These data suggest that V1 vasopressin receptors are present on SCLC cells.
Hong
M
M
Department of Biochemistry and Molecular Biology, George Washington University School of Medicine and Health Sciences, Washington, DC 20037.
Moody
T W
TW
D001127:Arginine Vasopressin / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism*; D018288:Carcinoma, Small Cell / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D006801:Humans; D008175:Lung Neoplasms / Q000378:metabolism*; D010121:Oxytocin / Q000494:pharmacology; D011945:Receptors, Angiotensin / Q000145:classification / Q000187:drug effects / Q000378:metabolism; D017483:Receptors, Vasopressin; D011994:Recombinant Proteins; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000378:metabolism
D011945:Receptors, Angiotensin; D017483:Receptors, Vasopressin; D011994:Recombinant Proteins; D001127:Arginine Vasopressin; D013373:Substance P; D010121:Oxytocin; C050702:substance P, Arg(1)-Pro(2)-Trp(7,9)-Leu(11)-; D002118:Calcium