Vasoactive intestinal polypeptide ( @entity10299 ) has been found in pancreatic nerves in several species. Studies were conducted to determine if @entity10299 could be a parasympathetic neurotransmitter in the @entity235 endocrine pancreas. To verify that @entity10299 is localized in pancreatic parasympathetic nerves, sections of @entity235 pancreas were immunostained for @entity10299 . @entity10299 staining was identified in the majority of neuronal cell bodies in intrapancreatic parasympathetic ganglia. In addition. @entity10299 was localized in nerve fibers innervating pancreatic islets in the proximity of alpha cells. Next, to determine if @entity10299 is released during electrical stimulation of parasympathetic nerves, pancreatic spillover of @entity10299 was measured during vagal nerve stimulation (VNS) in anesthetized @entity235 . @entity10299 spillover increased from a baseline of 630+/-540 pg/min to 2580+/-540 pg/min (delta = +1950+/-490 pg/min, p <0.01). Pancreatic @entity10299 release during VNS was not affected by @entity3897 , whereas ganglionic blockade with @entity4033 nearly abolished the @entity10299 response to VNS (p<0.005 vs control), suggesting that @entity10299 is a postganglionic neurotransmitter in the @entity235 pancreas. To examine the effects of @entity10299 on pancreatic hormone secretion, synthetic @entity10299 was infused locally into the pancreatic artery. @entity10299 , at a low dose (5 pmol/min), increased glucagon secretion from 1750+/-599 to 3800+/-990 pg/min (delta = +2060+/-870 pg/min, p<0.05), but did not affect insulin secretion (delta = -1030+/-760 microU/min, NS). Thus, @entity10299 is contained in and released from pancreatic parasympathetic nerves in proximity to islet alpha cells and exogenous @entity10299 , at a dose which approximates the increase of @entity10299 spillover during VNS, preferentially stimulates glucagon vs insulin secretion. Therefore, @entity10299 is likely to function as a parasympathetic neurotransmitter in the endocrine pancreas in @entity235 . We hypothesize that @entity10299 could mediate the glucagon response to parasympathetic activation which has been shown to resistant to cholinergic blockade with @entity3897 in several species.

Evidence that vasoactive intestinal polypeptide is a parasympathetic neurotransmitter in the endocrine pancreas in XXXX .

@entity235 :: ('9615', 'Species') :: ['canine', 'dog', 'dogs'] @entity4033 :: ('MESH:D018738', 'Chemical') :: ['hexamethonium'] @entity10299 :: ('484038(Tax:9615)', 'Gene') :: ['VIP'] @entity3897 :: ('MESH:D001285', 'Chemical') :: ['atropine']
@entity235 :: (9615,Species) :: ['dogs']
