TY - JOUR T1 - A test for antinociceptive activity of narcotic and narcotic antagonist analgesics in the guinea pig. JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 311 LP - 316 VL - 197 IS - 2 AU - D G Teiger Y1 - 1976/05/01 UR - http://jpet.aspetjournals.org/content/197/2/311.abstract N2 - Ethylenediamine tetraacetic acid (EDTA) was used as a nociceptive stimulus intradermally in the guinea pig. The responses evoked by EDTA included vocalization, biting and scratching at the site of injection and escape behavior. Nociception by EDTA was shown to be the result of its cation chelating activity. The suppression of EDTA-induced responses proved to be a rapid and effective antinociceptive test. The narcotic analgesics morphine, codeine, meperidine and methadone and the narcotic antagonist analgesics cyclazocine, cyclorphan, nalorphine and pentazocine were active. The slopes of the dose-response curves of the narcotic antagonist analgesics were significantly shallower than those of the narcotic analgesics. The test was highly specific for these analgesics. Antipyretic analgesics and various nonanalgesic drugs were inactive. ER -