@entity788 contain noradrenergic nerve terminals whose role in ganglionic transmission is unknown. Intracellular recordings from @entity95 pancreatic neurons were used to study the effects of alpha-adrenergic agonists and antagonists on ganglionic transmission and to determine if endogenously released @entity1063 contributed to synaptic @entity308 . Significant regional differences in alpha adrenergic effects were observed. In neurons from @entity21 of the head/neck region @entity1063 or selective alpha(2) agonists presynaptically inhibited ganglionic transmission and this effect was antagonized by the alpha(2) antagonist @entity3160 . In the majority of cells membrane hyperpolarization accompanied presynaptic inhibition during superfusion of alpha(2) agonists. Repetitive nerve stimulation evoked a presynaptic @entity308 ( @entity308 ) of ganglionic transmission in all neurons tested. A combination of @entity5554 (selective inhibitor of the @entity1063 transporter) and @entity6114 (releaser of endogenous @entity2661 ) increased @entity308 . Pretreatment with @entity1338 inhibited synaptic transmission and abolished @entity308 while @entity3160 did not affect it. Pretreatment with @entity2997 (>or=3.5 h) also failed reduce @entity308 while neurons unresponsive to alpha(2) adrenoceptor agonists routinely exhibited @entity308 , implying the presence of other inhibitory neurotransmitters sharing a common presynaptic mechanism with alpha(2) agonists. In the majority of neurons from @entity21 of the body region superfusion of @entity1063 or the selective alpha(1) agonist @entity2647 evoked membrane depolarization and facilitated ganglionic transmission. These effects were antagonized by the alpha(1) antagonist @entity3159 . The remaining neurons exhibited either alpha(2)-mediated synaptic inhibition or no-response. In conclusion, inhibitory alpha(2) and excitatory alpha(1) adrenoceptors exist in pancreatic @entity21 and predominate in the head/neck and body, respectively. @entity1063 , released during repetitive nerve stimulation, may contribute to synaptic @entity308 in the head/neck region and appeared to share a common mechanism with other, unidentified neurotransmitters mediating synaptic @entity308 in both regions. These differences indicate a functional heterogeneity of pancreatic sympathetic innervation that may reflect the reported regional differences in exocrine and endocrine cells.

Alpha-adrenergic modulation of synaptic transmission in XXXX pancreatic @entity21 .

@entity5554 :: ('MESH:C011386', 'Chemical') :: ['nisoxetine'] @entity3160 :: ('MESH:D015016', 'Chemical') :: ['yohimbine'] @entity788 :: ('MESH:D010190', 'Disease') :: ['Pancreatic ganglia'] @entity308 :: ('MESH:D003866', 'Disease') :: ['post-train depression', 'PTD', 'depression'] @entity2997 :: ('MESH:D006145', 'Chemical') :: ['guanethidine'] @entity3159 :: ('MESH:D011224', 'Chemical') :: ['prazosin'] @entity95 :: ('9986', 'Species') :: ['rabbit'] @entity2647 :: ('MESH:D010656', 'Chemical') :: ['phenylephrine'] @entity1338 :: ('MESH:D003000', 'Chemical') :: ['clonidine'] @entity21 :: ('MESH:D001480', 'Disease') :: ['ganglia'] @entity2661 :: ('MESH:D002395', 'Chemical') :: ['catecholamines'] @entity1063 :: ('MESH:D009638', 'Chemical') :: ['Norepinephrine', 'norepinephrine'] @entity6114 :: ('MESH:D014439', 'Chemical') :: ['tyramine']
@entity95 :: (9986,Species) :: ['rabbit']
