TY - JOUR
T1 - Contribution of different opioid systems to footshock-induced analgesia and motor suppression
AU - Nabeshima, Toshitaka
AU - Yamada, Kiyofumi
AU - Kameyama, Tsutomu
PY - 1983/9/2
Y1 - 1983/9/2
N2 - Mice, subjected to footschock, showed a significant increase of pain threshold and motor suppression immediately after the footshock and both effects magnitude of footshock-induced analgesia, but not motor suppression, was significantly less in morphine-tolerant mice than in non-tolerant mice. On the other hand, the magnitude of motor suppression, but not analgesia, was significantly less in ethylketocyclazocine- and pentazocine-tolerant mice than in non-tolerant mice. Furthermore, the apparent development of tolerance to both phenomena by successive daily footshocks was strikingly different. Tolerance to footshock-induced analgesia was induced on day 4 by the successive footshocks, while tolerance to motor suppresion was not observed until day 17 of successive daily footshocks. In addition, the antinociceptive effect of morphine was significantly attenuated in mice tolerant to footshock-induced analgesia. These results suggest that different opioid systems may participate in footshock-induced analgesia and motor suppression. In addition, it is suggested that footshock-induced analgesia may be mediated by μ and/or δ receptors and motor suppression may be mediated by κ and/or δ receptors.
AB - Mice, subjected to footschock, showed a significant increase of pain threshold and motor suppression immediately after the footshock and both effects magnitude of footshock-induced analgesia, but not motor suppression, was significantly less in morphine-tolerant mice than in non-tolerant mice. On the other hand, the magnitude of motor suppression, but not analgesia, was significantly less in ethylketocyclazocine- and pentazocine-tolerant mice than in non-tolerant mice. Furthermore, the apparent development of tolerance to both phenomena by successive daily footshocks was strikingly different. Tolerance to footshock-induced analgesia was induced on day 4 by the successive footshocks, while tolerance to motor suppresion was not observed until day 17 of successive daily footshocks. In addition, the antinociceptive effect of morphine was significantly attenuated in mice tolerant to footshock-induced analgesia. These results suggest that different opioid systems may participate in footshock-induced analgesia and motor suppression. In addition, it is suggested that footshock-induced analgesia may be mediated by μ and/or δ receptors and motor suppression may be mediated by κ and/or δ receptors.
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U2 - 10.1016/0014-2999(83)90287-X
DO - 10.1016/0014-2999(83)90287-X
M3 - Article
C2 - 6138260
AN - SCOPUS:0020636394
SN - 0014-2999
VL - 92
SP - 199
EP - 205
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
IS - 3-4
ER -