Neuronal differentiation modifies the effect of ethanol exposure on voltage-dependent calcium channels in NG 108-15 cells.
The effect of prolonged (72 h) ethanol (200 mM) exposure on the labeling of L-type (using tritiated PN 200-110) and N-type (using iodinated omega-conotoxin) voltage-dependent calcium channels was investigated in cultured NG 108-15 cells. In undifferentiated cells ethanol produced an 80% increase in PN 200-110 Bmax and no changes in omega-conotoxin binding. Differentiation had a profound effect on the response of cells to ethanol, which in differentiated neuron-like cells decreased omega-conotoxin binding (-53.5%) leaving PN 200-110 labeling of L-type channels unaffected. The effect was time dependent and reversible upon ethanol withdrawal. The decreased omega-conotoxin binding was accompanied by a reduced ability of omega-conotoxin to inhibit K+ -stimulated calcium uptake. The results demonstrate that in cultured NG 108-15 cells ethanol differentially affects DHP and omega-conotoxin-sensitive, voltage-dependent calcium channels and that the effect is also modulated by differentiation of the cell to a neuronal phenotype.
Bergamaschi
S
S
Institute of Pharmacological Sciences, University of Milan, Italy.
Battaini
F
F
Trabucchi
M
M
Parenti
M
M
Lopez
C M
CM
Govoni
S
S
D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000378:metabolism / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects*; D002454:Cell Differentiation; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D004594:Electrophysiology; D000431:Ethanol / Q000494:pharmacology*; D016257:Fura-2; D006822:Hybrid Cells / Q000187:drug effects; D015640:Ion Channel Gating / Q000187:drug effects*; D017275:Isradipine / Q000378:metabolism / Q000494:pharmacology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010455:Peptides / Q000378:metabolism / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D014407:Tumor Cells, Cultured; D020866:omega-Conotoxin GVIA
D002121:Calcium Channel Blockers; D015220:Calcium Channels; D002492:Central Nervous System Depressants; D010455:Peptides; D000431:Ethanol; D003994:Bucladesine; D011189:Potassium Chloride; D020866:omega-Conotoxin GVIA; D016257:Fura-2; D017275:Isradipine