XXXX tolerance and physical @entity734 : influence of cholinergic agonists and antagonists.

@entity19 @entity1337 @entity12864 @entity1510 @entity1617 @entity5592 @entity3897 @entity1286 @entity2607 @entity5591 @entity734 @entity934
The effects of centrally acting agents which alter cholinergic activity were assessed in @entity19 rendered tolerant to and dependent on @entity1286 (M @entity19 ) and in naive @entity19 ( @entity19 ). In both N and M @entity19 , @entity2607 potentiated @entity1286 @entity1337 slightly, and this action was blocked by @entity3897 and @entity5591 . When administered 10 min before @entity1510 in dependent @entity19 @entity3897 enhanced precipitated withdrawal jumping; when given 30 min before @entity1510 , @entity3897 produced an inhibition of the response. @entity2607 abd @entity5592 greatly inhibited the jumping response, while @entity12864 had no effect. The inhibitory effect of @entity2607 on @entity1510 precipitated withdrawal jumpimg was reversed by @entity3897 and @entity5591 but @entity3897 did not alter @entity1286 tolerance and @entity734 development. Brain @entity934 ( @entity1617 ) levels in both N and M @entity19 were increased by @entity2607 , the increase being greater in M @entity19 . This increase was blocked by prior administration of @entity3897 or @entity5591 . When @entity3897 was administered to M @entity19 10 min before sacrifice, brain AC-h levels decreased. However, when brain @entity1617 levels were determined 30 min after @entity3897 , no change was found. It was concluded that @entity1617 does not play a major direct role in the development of tolerance and @entity734 , but that @entity1617 is involved in the manifestations of acute @entity1286 effects and in some of the withdrawal signs in the dependent state.
