title: Neuromodulatory role of 5-hydroxytryptamine type 1A receptors on the excitability of Renshaw cells in the rat spinal cord.
abstract: Serotonin modulates neurotransmission at synapses between various spinal neurons and, thus, may either facilitate or depress the information processed in the circuits and ultimately modulate the final motor output. A possible neuromodulatory role of 5-hydroxytryptamine type 1A (5-HT1A) receptors on the excitability of lumbar spinal Renshaw cells was explored in anesthetized rats spinalized at T4 level. Intravenous administration of the specific 5-HT1A agonist (2R)-(+)-8-hydroxy-2-(di-n-propylamino)tetralin hydrobromide (8-OH-DPAT) (0.1 mg/kg) decreased the Renshaw cell burst response by 20-45%. This effect was completely antagonized by the specific 5-HT1A antagonist (S)-N-tert-butyl-3-(4-(2-methoxyphenyl)-piperazin-1-yl)-2-phenylpropanamide dihydrochloride [(S)-WAY 100135] (0.1 mg/kg, intravenous), although this drug per se had no effect on the Renshaw cell burst response. These results suggest that 8-OH-DPAT-induced decrease in Renshaw cell burst firing was mediated by 5-HT1A receptors located either presynaptically or postsynaptically.
authors.affiliation: Division of Pharmacology and Experimental Therapeutics, Indian Institute of Chemical Biology, Kolkata, West Bengal, India. gajendiran.mahadevan@vanderbilt.edu
authors.forename: Mahadevan
authors.initials: M
authors.lastname: Gajendiran
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology; D000200:Action Potentials / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D004347:Drug Interactions; D007395:Interneurons / Q000187:drug effects / Q000502:physiology*; D008161:Lumbosacral Region; D008297:Male; D010879:Piperazines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044282:Receptor, Serotonin, 5-HT1A / Q000502:physiology*; D012702:Serotonin Antagonists / Q000494:pharmacology; D017366:Serotonin Receptor Agonists / Q000494:pharmacology; D013116:Spinal Cord / Q000166:cytology*
chemical_list: D010879:Piperazines; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; D044282:Receptor, Serotonin, 5-HT1A; C081293:WAY 100135; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin