HYPERALGESIA IN MICE LACKING THE KV1.1 POTASSIUM CHANNEL GENE

Hyperalgesia and morphine induced antinociception were measured in mic e lacking the gene for the Shaker-like voltage-gated potassium channel Kv1.1 alpha subunit. The effects of varying gene dosage were studied by comparing homozygous null (-/-) versus heterozygous (+/-) and wildt ype (+/+) littermates. Hyperalgesia was measured using the paw flick a ssay, hot plate assay and formalin induced hind paw licking. It was ob served thar null mutant animals had significantly shorter latencies to response in the paw flick (36%) and hot plate (27%) assays while thei r licking times after hind paw injection of formalin was increased in both the first (74%) and second (65%) phases of the response compared to wildtype controls. Morphine induced antinociception in Kv1.1 null m utant animals was blunted. These studies indicate that Kv1.1 plays an important role in nociceptive and antinociceptive signaling pathways. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.