title: Analgesic effects of intracerebroventricular administration of calcium channel blockers in mice.
abstract: 1. The antinociceptive action of calcium channel blockers administered intracerebroventricularly to mice using the acetic acid writhing test was studied. 2. The drugs produced dose-dependent inhibition of the number of writhes induced by the intraperitoneal administration of 10 ml/kg of 0.6% acetic acid. 3. The CaCBs may be ranked from most to least potent as follows: verapamil > nimodipine > diltiazem > flunarizine > nifedipine > cinnarizine. 4. Since naloxone pretreatment was not able to inhibit the antinociception produced by CaCBs an opioid mechanism of action is excluded. 5. It is suggested that CaCBs can induce analgesia through a decrease in cellular Ca2+ availability, increasing the nociceptive threshold.
authors: Department of Pharmacology, Faculty of Medicine, Universidad de Chile, Santiago.
authors: H F
authors: HF
authors: Miranda
authors: T
authors: T
authors: Pelissier
authors: F
authors: F
authors: Sierralta
mesh_terms: D000700:Analgesics / Q000494:pharmacology*; D000818:Animals; D002121:Calcium Channel Blockers / Q000008:administration & dosage / Q000494:pharmacology*; D004095:Dihydropyridines / Q000008:administration & dosage / Q000494:pharmacology; D004110:Diltiazem / Q000008:administration & dosage / Q000494:pharmacology; D007276:Injections, Intraventricular; D051379:Mice; D009270:Naloxone / Q000494:pharmacology; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects; D010879:Piperazines / Q000008:administration & dosage / Q000494:pharmacology; D014700:Verapamil / Q000008:administration & dosage / Q000494:pharmacology
chemical_list: D000700:Analgesics; D002121:Calcium Channel Blockers; D004095:Dihydropyridines; D010879:Piperazines; D009270:Naloxone; D014700:Verapamil; D004110:Diltiazem