Effects of intrathecally administered aminoglycoside antibiotics, calcium-channel blockers, nickel and calcium on acetic acid-induced writhing test in mice

1. Antinociceptive effects of intrathecally administered aminoglycoside antibiotics, cal cium-channel blockers, nickel and calcium ions on the acetic acid-induced writhing test in mice were examined, 2. Neomycin (0.5-20.0 mu g/mouse) gentamicin (5-40 mu g/mouse), nicardipine, diltiazem and verapamil (0.5-80.0 mu g/mouse) and calcium ions (0.02-1.0 mu mol/mouse) exerted a dose-dependent antinociceptive activity on the acetic acid-induced writhing test. Nickel ions ( 2.5, 5.0 and 10.0 mu mol/mouse) were found ineffective in this test. 3. These results suggest that N- and L-type, but not T-type, voltage dependent calcium channels are implicated in the spinal processing of nociceptive information. (C) 1998 Elsevier Science Inc.