Potassium- and carbachol-evoked release of [3H]noradrenaline from human neuroblastoma cells, SH-SY5Y.
The human neuroblastoma clone SH-SY5Y expresses potassium-, carbachol-, and calcium ionophore A23187-evoked, calcium-dependent release of [3H]noradrenaline. Release in response to carbachol and potassium was greater than additive. Atropine (Ki = 0.33 nM), hexahydrosiladifenidol (Ki = 18 nM), and pirenzepine (Ki = 1,183 nM) completely inhibited the carbachol-evoked noradrenaline release, an order of potency suggesting that an M3 receptor was linked to release. In contrast, noradrenaline release was only partially inhibited by the M2-selective antagonists methoctramine (10(-4) M) and AFDX-116 (10(-4) M), by approximately 14 and 46%, respectively. The nicotinic antagonist d-tubocurarine (10(-4) M) resulted in a partial inhibition of release, a finding suggesting that a nicotinic receptor may also be involved. SH-SY5Y provides a suitable cell line in which to study the biochemical mechanisms underlying the cholinergic receptor regulation of noradrenaline release.
Murphy
N P
NP
Department of Cardiovascular Studies, University of Leeds, England.
Ball
S G
SG
Vaughan
P F
PF
D000001:Calcimycin / Q000494:pharmacology; D002122:Calcium Chloride / Q000494:pharmacology; D002217:Carbachol / Q000494:pharmacology*; D004533:Egtazic Acid / Q000494:pharmacology; D006801:Humans; D009116:Muscarine / Q000037:antagonists & inhibitors; D009447:Neuroblastoma / Q000378:metabolism*; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010277:Parasympathomimetics / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology*; D014316:Tritium; D014407:Tumor Cells, Cultured
D010277:Parasympathomimetics; D014316:Tritium; D000001:Calcimycin; D004533:Egtazic Acid; D009116:Muscarine; D002217:Carbachol; D002122:Calcium Chloride; D011188:Potassium; D009638:Norepinephrine