Galanin in the regulation of pancreatic vascular perfusion.
OBJECTIVE
Acute pancreatitis is associated with compromised pancreatic microcirculation. Galanin is a vasoactive neuropeptide, but its role in the regulation of pancreatic vascular perfusion (PVP) is unclear.


METHODS
Localization of galanin immunoreactivity was investigated by immunohistochemistry, and the effects of bolus doses of galanin or the antagonist galantide on blood pressure (BP) and PVP (by laser Doppler fluxmetry) were determined in anesthetized possums.


RESULTS
Galanin immunoreactivity was abundant in the possum pancreas particularly around blood vessels. Galanin (0.001-10 nmol) produced a dose-dependent increase in BP (to 177% of baseline) and a complex PVP response consisting of a transient increase, then a fall below baseline with recovery to above baseline. Galantide (0.003-30 nmol) caused a dose-dependent biphasic response in BP, with a reduction, recovery, then a further fall, followed by recovery, whereas PVP increased (178%) then fell (to 56%) of baseline. Similar effects were produced by continuous intravenous infusion of galanin (1 and 10 nmol) or galantide (3 and 30 nmol). The second-phase response of these agents is probably a passive response of the pancreatic vasculature to systemic cardiovascular effects.


CONCLUSIONS
These data suggest that galanin acutely reduces PVP, whereas galantide increases it, implying galanin may be important in the regulation of PVP.
Brooke-Smith
Mark E
ME
Department of General and Digestive Surgery, Flinders Medical Centre, Flinders University, Bedford Park, South Australia, Australia.
Carati
Colin J
CJ
Bhandari
Mayank
M
Toouli
James
J
Saccone
Gino T P
GT
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D005260:Female; D019004:Galanin / Q000031:analogs & derivatives / Q000494:pharmacology / Q000502:physiology*; D007150:Immunohistochemistry; D008297:Male; D008833:Microcirculation / Q000187:drug effects / Q000502:physiology; D010179:Pancreas / Q000098:blood supply* / Q000187:drug effects / Q000502:physiology; D044088:Receptors, Galanin / Q000037:antagonists & inhibitors / Q000502:physiology; D012039:Regional Blood Flow / Q000187:drug effects; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology; D048330:Trichosurus
D044088:Receptors, Galanin; C074975:galantide; D013373:Substance P; D019004:Galanin