Inhibitory effects of galanin on the isolated spinal cord of the newborn rat.
The effects of galanin, a 29-amino-acid peptide, on spinal reflexes were studied. In the isolated hemisected spinal cord of the newborn rat, galanin (0.1-5 microM) depressed the monosynaptic reflex that was induced by dorsal root stimulation and recorded from the corresponding ventral root. In the isolated spinal cord-tail preparation of the newborn rat, galanin (0.3-0.6 microM) depressed the nociceptive reflex that was induced by application of capsaicin to the tail and recorded from a lumbar ventral root. In both preparations the inhibitory effects of galanin were reversible and the full recovery of the reflexes was observed within 3-20 min after removal of the peptide. The mechanisms of action of galanin on the spinal reflexes and the physiological role of the peptide in the spinal cord are discussed.
D000818:Animals; D002211:Capsaicin / Q000494:pharmacology; D019004:Galanin; D008564:Membrane Potentials / Q000187:drug effects; D009433:Neural Inhibition / Q000187:drug effects*; D009479:Neuropeptides / Q000494:pharmacology*; D010455:Peptides / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D012023:Reflex, Monosynaptic / Q000187:drug effects*; D013116:Spinal Cord / Q000503:physiopathology; D013126:Spinal Nerve Roots / Q000187:drug effects
D009479:Neuropeptides; D010455:Peptides; D019004:Galanin; D002211:Capsaicin