Determinants of the stimulatory opioid effect on intracellular calcium in SK-N-SH and NG108-15 neuroblastoma.
The opiate agonist etorphine elevated [Ca2+]i in two neuroblastoma cell lines. Fura-2 imaging of single cells revealed a small and variable calcium elevation in only 20% of cultures. Three factors were found to increase the probability (up to 70%) and the amplitude of the response to etorphine: (a) synchronization of the cultures; (b) differentiation of the cells; and (c) synergism with other stimulatory agents (carbachol in SK-N-SH and bradykinin in NG108-15 cells). The establishment of a reproducible experimental protocol may facilitate the study of the molecular mechanism(s) underlying the stimulatory activity of opiates.
Sarne
Y
Y
Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Israel.
Gafni
M
M
D001920:Bradykinin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology; D002454:Cell Differentiation; D004357:Drug Synergism; D005048:Etorphine / Q000494:pharmacology*; D016257:Fura-2; D007425:Intracellular Membranes / Q000378:metabolism*; D009294:Narcotics / Q000494:pharmacology*; D009447:Neuroblastoma / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors; D014407:Tumor Cells, Cultured
D009294:Narcotics; D005048:Etorphine; D002217:Carbachol; D001920:Bradykinin; D002118:Calcium; D016257:Fura-2