1. The effects of infusions of the cholinomimetic drugs @entity934 , @entity2710 , @entity11039 , @entity5402 , @entity6327 and @entity2134 were examined on vasoconstrictor responses of the perfused @entity95 ear artery to sympathetic nerve stimulation and to injections of @entity1063 .2. The first effect of very low concentrations of @entity934 or @entity11039 was a slight enhancement of responses to sympathetic nerve stimulation, but when higher concentrations of @entity934 , @entity2710 , @entity11039 , @entity5402 and @entity6327 were infused, these vasoconstrictor responses were decreased. With still higher concentrations the responses tended to increase in size during the infusion. After stopping an infusion, the depressed vasoconstrictor responses rapidly recovered and became enhanced.3. Infusions of @entity2134 in a wide range of concentrations generally caused enhancement of responses.4. The depressant effects of cholinomimetic drugs on the responses to sympathetic nerve stimulation were antagonized by @entity3897 . Larger concentrations of the drugs overcame the blockade by @entity3897 .5. The effects of @entity934 , @entity2710 and @entity11039 on the responses to sympathetic nerve stimulation were more pronounced at low than at high frequencies of stimulation.6. Vasoconstrictor responses to injected @entity1063 were enhanced by @entity934 or @entity2710 , whereas responses to sympathetic nerve stimulation were decreased by the same concentrations of these choline @entity14743 .7. It is suggested that cholinomimetic drugs may act on receptor sites associated with the adrenergic terminal axon and that they may facilitate or impair the release of @entity1063 and impair @entity1063 uptake.

The effects of cholinomimetic drugs on responses to sympathetic nerve stimulation and XXXX in the @entity95 ear artery.

@entity14743 :: ('MESH:D004952', 'Chemical') :: ['esters'] @entity95 :: ('9986', 'Species') :: ['rabbit'] @entity2134 :: ('MESH:D010862', 'Chemical') :: ['pilocarpine'] @entity11039 :: ('MESH:D009116', 'Chemical') :: ['muscarine'] @entity3897 :: ('MESH:D001285', 'Chemical') :: ['atropine'] @entity1063 :: ('MESH:D009638', 'Chemical') :: ['noradrenaline'] @entity2710 :: ('MESH:D016210', 'Chemical') :: ['methacholine'] @entity6327 :: ('MESH:D001115', 'Chemical') :: ['arecoline'] @entity5402 :: ('MESH:D002217', 'Chemical') :: ['carbachol'] @entity934 :: ('MESH:D000109', 'Chemical') :: ['acetylcholine']
@entity1063 :: (MESH:D009638,Chemical) :: ['noradrenaline']
