Renal vasodilatation after central administration of galanin

Galanin, a recently described brain-gut neuropeptide, exists in central nervous pathways subserving cardiovascular regulation in the rat. To investigate the possibility that this peptide is involved in the central control of cardiovascular function we administered galanin (1 or 5 nmol) into a lateral cerebral ventricle in conscious, Long-Evans and Brattleboro rats, chronically instrumented with pulsed Doppler probes for monitoring regional haemodynamics. In both strains galanin caused renal vasodilatation at a dose that had no significant effects on blood pressure or heart rate. These results highlight the need to monitor regional haemodynamics when assessing putative physiological roles of peptides in central cardiovascular regulation.