Hyperactivity caused by a nitric oxide synthase inhibitor is countered by ultra-wideband pulses

Potential action of ultra-wideband (UWB) electromagnetic field pulses on ef fects of N-G-nitro-L-arginine methyl ester (L-NAME), an inhibitor of nitric oxide synthase (NOS), on nociception and locomotor activity was investigat ed in CF-1 mice. Animals were injected TP with saline or 50 mg/kg L-NAME an d exposed for 30 min to no pulses (sham exposure) or UWB pulses with electr ic field parameters of 102 +/- 1 kV/m peak amplitude, 0.90 +/- 0.05 ns dura tion, and 160 +/- 5 ps rise time (mean +/- S.D.) at 600/s. Animals were tes ted for thermal nociceptive responses on a 50 degrees C surface and for spo ntaneous locomotor activity for 5 min. L-NAME by itself increased mean firs t-response (paw lift, shake, or lick; jump) and back-paw-lick response late ncies and mean locomotor activity. Exposure to UWB pulses reduced the L-NAM E-induced increase in back-paw-lick latency by 22%, but this change was not statistically significant. The L-NAME-induced hyperactivity was not presen t after UWB exposure. Reduction and cancellation of effects of L-NAME sugge st activation of opposing mechanism(s) by the UWB pulses, possibly includin g increase of nitric oxide production by NOS. The action, or actions, of UW B pulses appears to be more effective on locomotor activity than on thermal nociception in CF-1 mice. Bioelectromagnetics 20:431-439, 1999. (C) 1999 W iley-Liss, Inc.