caa a22 4500 465737439 CHVBK 20180323111758.0 cr unu---uuuuu 170327e19901201xx s 000 0 eng 10.1007/BF02247133 doi (NATIONALLICENCE)springer-10.1007/BF02247133 Antinociceptive effects of elevated plus-maze exposure: influence of opiate receptor manipulations [Elektronische Daten] [Claire Lee, R. Rodgers] It has been suggested that anxiety may be a critical factor in certain forms of non-opioid environmental analgesia. In the present study, 5-min exposure to the elevated plus-maze test of anxiety (EPM) induced a mild, though enduring, elevation in tail-flick latencies in male mice. Pretreatment with the opiate antagonist naltrexone (0.1-10.0 mg/kg) failed to block EPM-induced antinociception; indeed, the highest dose actuallyenhanced the response. This effect could not be attributed to intrinsic analgetic activity of naltrexone. Rather, analysis of EPM behaviours suggested that it may have been secondary to an anxiogenic effect of the compound. The involvement of non-opioid substrates in this form of pain inhibition was further supported by the failure of chronic morphine treatment (7 days; 7.5 mg/kg) to alter either the antinociceptive or behavioural response to EPM exposure. Irrespective of treatment history, mice showed a retest EPM profile of enhanced anxiety, with tail-flick data suggesting a major contribution of anticipatory factors. Several important methodological variables are discussed and findings are contrasted with parallel studies on non-opioid defeat analgesia. Springer-Verlag, 1990 Elevated plus-maze nationallicence Anxiety nationallicence Antinociception nationallicence Opioid nationallicence Non-opioid nationallicence Naltrexone nationallicence Morphine nationallicence Mice nationallicence Lee Claire Department of Psychology, University of Bradford, BD7 1DP, Bradford, UK aut Rodgers R. Department of Psychology, University of Leeds, LS2 9JT, Leeds, UK aut Psychopharmacology Springer-Verlag 102/4(1990-12-01), 507-513 0033-3158 102:4<507 1990 102 213 https://doi.org/10.1007/BF02247133 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF02247133 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lee Claire Department of Psychology, University of Bradford, BD7 1DP, Bradford, UK aut NATIONALLICENCE 700 1- Rodgers R. Department of Psychology, University of Leeds, LS2 9JT, Leeds, UK aut NATIONALLICENCE 773 0- Psychopharmacology Springer-Verlag 102/4(1990-12-01), 507-513 0033-3158 102:4<507 1990 102 213 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer