In addition to quantal, vesicular release of @entity934 ( @entity3451 ), there is also non-quantal release at the motor endplate which is insufficient to evoke postsynaptic responses unless @entity4360 ( @entity4360 ) is inhibited. We here addressed potential non-quantal release in the @entity19 @entity825 by organ bath experiments and (immuno)histochemical methods. Electrical field stimulation (EFS) of nerve terminals elicited tracheal constriction that is largely due to @entity3451 release. Classical enzyme histochemistry demonstrated @entity4360 ( @entity4360 ) activity in nerve fibers in the muscle and @entity21937 ( @entity21937 ) activity in the smooth muscle cells. Acute inhibition of both esterases by @entity2607 significantly raised tracheal tone which was fully sensitive to @entity3897 . This effect was reduced, but not abolished, in @entity4360 , but not in @entity21937 gene-deficient @entity19 . The @entity2607 -induced increase in tracheal tone was unaffected by @entity2568 (10(-5)M), an inhibitor of the vesicular @entity934 transporter, and by @entity2819 (10(-4)M), an inhibitor of organic cation transporters. @entity11348 -3, in low concentrations an inhibitor of the high-affinity @entity1877 transporter-1 ( @entity68151 ), completely abrogated the @entity2607 effects when applied in high concentrations (10(-4)M) pointing towards an involvement of low-affinity @entity1877 transporters. To evaluate the cellular sources of non-quantal @entity3451 release in the @entity825 , expression of low-affinity @entity1877 transporter-like family (CTL1-5) was evaluated by RT-PCR analysis. Even though these transporters were largely abundant in the epithelium, denudation of airway epithelial cells had no effect on @entity2607 -induced tracheal contraction, indicating a non-quantal release of @entity3451 from non-epithelial sources in the airways. These data provide evidence for an epithelium-independent non-vesicular, non-quantal @entity3451 release in the @entity19 @entity825 involving low-affinity @entity1877 transporters.

Cholinergic activation of the XXXX trachealis muscle via non-vesicular @entity934 release involving low-affinity @entity1877 transporters.

@entity825 :: ('MESH:D055090', 'Disease') :: ['trachea'] @entity19 :: ('10090', 'Species') :: ['mice', 'mouse'] @entity21937 :: ('12038(Tax:10090)', 'Gene') :: ['BChE', 'butyrylcholinesterase'] @entity4360 :: ('11423(Tax:10090)', 'Gene') :: ['AChE', 'acetylcholinesterase'] @entity2819 :: ('MESH:D003345', 'Chemical') :: ['corticosterone'] @entity1877 :: ('MESH:D002794', 'Chemical') :: ['choline'] @entity2568 :: ('MESH:C006189', 'Chemical') :: ['vesamicol'] @entity3897 :: ('MESH:D001285', 'Chemical') :: ['atropine'] @entity3451 :: ('D000109', 'Chemical') :: ['ACh'] @entity2607 :: ('MESH:D010830', 'Chemical') :: ['eserine'] @entity68151 :: ('63993(Tax:10090)', 'Gene') :: ['CHT1'] @entity11348 :: ('MESH:D006426', 'Chemical') :: ['Hemicholinium'] @entity934 :: ('MESH:D000109', 'Chemical') :: ['acetylcholine']
@entity19 :: (10090,Species) :: ['murine']
