Characterization of acute somatosensory pain transmission in P/Q-type Ca2+channel mutant mice, leaner

To study the role of the Ca(v)2.1/alpha (1A) (P/Q-type) Ca2+ channel in som atosensory pain processing, behavioral and electrophysiological studies wer e conducted using the leaner (tg(la)/tg(la)) mouse. Behavioral analyses in tg(la)/tg(la) revealed reduced responses to mechanical stimuli, and enhance d responses to heat stimuli. Electrophysiological analyses showed that tg(l a)/tg(la) had a significantly reduced ability to evoke dorsal root potentia ls, suggesting a functional deficit in the spinal dorsal horn local circuit ry responsible for presynaptic inhibition of primary sensory fibers. These results suggest the critical importance of the P/Q-type channel in modulati on of acute somatosensory pain transmission in spinal cord. (C) 2001 Federa tion of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.