An investigation of XXXX receptors involved in antinociceptive effects of antidepressants.

@entity5554 @entity3160 @entity3974 @entity5081 @entity35 @entity5080 @entity406 @entity3755 @entity20368 @entity1153 @entity2645 @entity1154 @entity750 @entity3159 @entity6009 @entity1063
We attempted to determine which @entity1154 receptor subtypes are predominantly involved in antidepressant-induced antinociception. Antinociceptive effects were evaluated by using @entity406 tests with rats. Antidepressants acting as potent inhibitors of @entity1063 reuptake ( @entity5554 , @entity5080 , and @entity5081 ) or inhibiting reuptake of both @entity1063 and @entity750 ( @entity750 ) ( @entity2645 and @entity1153 ) induced dose-dependent antinociception. Simultaneous intraperitoneal administration of antidepressants and either @entity3159 (alpha(1) antagonist) or @entity6009 ( @entity750 (2) antagonist) significantly antagonized antinociceptive effects. @entity3755 (selective @entity750 reuptake inhibitor) induced antinociception less potently than other antidepressants and was significantly antagonized by @entity6009 , but not @entity3159 . Ondansetron ( @entity750 (3) antagonist) significantly antagonized antinociception by 10 mg/kg of @entity2645 . In contrast, @entity20368 ( @entity750 (4) antagonist) markedly enhanced antinociception by small-dose (2.5 mg/kg) @entity2645 . @entity2645 -induced antinociception was significantly antagonized by intracerebroventricular administration of @entity3159 or @entity6009 , but not by @entity3160 (alpha(2) antagonist) or @entity3974 , and was significantly enhanced by intracerebroventricularly administered SDZ-205,557. These findings suggest that alpha(1) adrenoceptors and @entity750 (2) receptors in the brain are involved in antidepressant-induced antinociception. In addition, the results suggested functional interactions between noradrenergic and serotonergic neurons as mechanisms for antidepressant-induced antinociception. IMPLICATIONS: Formalin tests of @entity35 treated with antidepressants and antagonists of @entity1154 receptors indicate that alpha(1) adrenoceptors, @entity750 ( @entity750 )(2) receptors, and @entity750 (3) receptors are involved in antidepressant-induced antinociception, suggesting functional interactions between noradrenergic and serotonergic neurons as mechanisms of antidepressant-induced antinociception.
