The effect of calcium channels blockers in the K+-evoked release of [3H]adenine nucleotides from rat brain cortical synaptosomes.
The role of L-,N-, P- and Q-type voltage-dependent calcium channels in K+-induced release of [3H]adenine nucleotides from rat brain cortical synaptosomes was investigated. Cd2+, a non-specific blocker of calcium channels, inhibited by 69% the release of the nucleotides induced by 33 mM K+. Nifedipine, omega-Conotoxin GVIA and omega-Agatoxin IVA had no effect whereas omega-Conotoxin MVIIC inhibited by 62% the K+ induced release of adenine nucleotides in rat brain cortical synaptosomes. It is concluded that Q-type calcium channels are directly involved in the release of adenine nucleotides in rat brain cortical synaptosomes.
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Departamento de Farmacologia, Instituto de Ciências Biológicas, UFMG, Minas Gerais, Brazil. gomez@mono.icb.ufmg.br
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Romano-Silva
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D000227:Adenine Nucleotides / Q000378:metabolism*; D000818:Animals; D002104:Cadmium / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D015220:Calcium Channels / Q000187:drug effects / Q000502:physiology*; D002540:Cerebral Cortex / Q000378:metabolism*; D005260:Female; D008297:Male; D008978:Mollusk Venoms / Q000494:pharmacology; D009543:Nifedipine / Q000494:pharmacology; D010455:Peptides / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013111:Spider Venoms / Q000494:pharmacology; D013574:Synaptosomes / Q000378:metabolism*; D014316:Tritium; D020867:omega-Agatoxin IVA; D020866:omega-Conotoxin GVIA; D020960:omega-Conotoxins
D000227:Adenine Nucleotides; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D008978:Mollusk Venoms; D010455:Peptides; D013111:Spider Venoms; D020867:omega-Agatoxin IVA; D020960:omega-Conotoxins; D002104:Cadmium; D014316:Tritium; C053423:Conus magus toxin; D020866:omega-Conotoxin GVIA; D009543:Nifedipine; D011188:Potassium