Intracerebroventricular secretin enhances pancreatic volume and bicarbonate response in rats.
BACKGROUND
Although secretin has been found within the brain, its central role in pancreatic exocrine function has not been previously addressed. The hypothesis that intracerebroventricular secretin enhances pancreatic volume and bicarbonate output at doses that have no effect when given intravenously was tested.


METHODS
Sprague-Dawley rats had a cannula stereotactically placed into the left lateral cerebral ventricle 24 hours before study. At laparotomy the bile and pancreatic ducts were separately cannulated and excluded for tared collections and bicarbonate assay.


RESULTS
Increasing doses of intracerebroventricular secretin (0.005, 0.05, and 0.5 microgram/1.0 microliter) induced a significant dose-related increase in bicarbonate output (2.95, 3.32, and 4.02 microEq/30 min, respectively) above basal (2.62 microEq/30 min) compared with control or intracerebroventricular saline treated animals. Pancreatic volume increased to 59.7 microliters at the lowest intracerebroventricular dose and increased (p < 0.025) to 65.8 microliters at the 0.05 intracerebroventricular secretin dose when compared with basal (59.4 microliters). To show that this was not a systemic effect of secretin, intravenous infusion of secretin at 0.005 and 0.05 microgram/kg/hr failed to stimulate either volume or bicarbonate output compared with that observed with intracerebroventricular secretin over the same dose range.


CONCLUSIONS
These observations indicate that intracerebroventricular secretin stimulates pancreatic volume and bicarbonate output and suggest that central secretin may play a role in the regulation of exocrine pancreatic secretion.
Conter
R L
RL
Department of Surgery, Pennsylvania State University, Milton S. Hershey Medical Center, Hershey 17033, USA.
Hughes
M T
MT
Kauffman
G L
GL
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism*; D001646:Bile / Q000187:drug effects / Q000378:metabolism*; D002552:Cerebral Ventricles / Q000187:drug effects / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D007276:Injections, Intraventricular; D007700:Kinetics; D008099:Liver / Q000187:drug effects; D008297:Male; D010179:Pancreas / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012633:Secretin / Q000494:pharmacology*; D013238:Stereotaxic Techniques; D013997:Time Factors
D001639:Bicarbonates; D012633:Secretin