A study of the Effect of Ghrelin on the Regulation of Pancreatic Exocrine Secretion in Male Albino Rats

The present work was done to investigate the role of ghrelin in the regulation of
pancreatic volume and protein secretion in anaesthetized male albino rats. The rats
were divided into 4 equal groups: First group Is the control group. Second group:
Pancreatic secretion was stimulated by infusion of wheat germ lectin, which is known
to be a stimulus of cholicystokinin hormone release, preceded by ghrelin infusion and
continued for one hour, this procedure was performed before and after acute
subdiaphragmatic vagotomy. Third group: was infused by 2-D-glucose, which acts as
central vagal stimulant, preceded by ghrelin infusion and continued for one hour
Fourth group: was infused by bethanechol, which is a cholinergic receptor agonist,
preceded by ghrelin infusion and continued for one hour. Then the pancreatic
secretion was collected after anaesthetizing male albino rat, through a cannula
inserted in the common bile duct. The results showed significant increase of the
protein content by wheat germ lectin infusion, through stimulation of cholicystokinin
which stimulated pancreatic secretion, Ghrelin caused significant inhibition of
protein secretion and this inhibition was continued after acute subdiaphragmatic
vagotomy, Ghrelin also caused significantinhibition of the pancreatic protein
secretion, which caused by central stimulation of vagus nerve by 2-D-glucose
infusion. Also, ghrelin showed significantinhibition of the pancreatic protein
secretion which caused by bethanechol, that acting as a muscarinic receptor agonist.
It is concluded that ghrelin is a potent inhibitor of pancreatic exocrine protein
secretion and the mechanism of its action may be directed at the level of the intra
pancreatic neurotransmission.