[Enhancement of taurine-activated whole-cell currents by serotonin in rat sacral dorsal commissural neurons].
Using nystatin-perforated whole-cell recording configuration, the modulatory effect of serotonin (5-hydroxytryptamine, 5-HT) on taurine (Tau)-activated current (ITau) was investigated in neurons dissociated from the rat sacral dorsal commissural nucleus (SDCN). The results are as follows: (1) Tau acted on strychnine-sensitive glycine (Gly) receptors and elicited inward currents at a holding potential (VH) of -40 mV in SDCN neurons; (2)in a range of 0.01 to 100 mumol/L, 5-HT enhanced ITau in a concentration-dependent manner; (3) both the reversal potential of Tau and the binding affinity of Tau to Gly receptor were not affected by 5-HT; (4) when the neurons were loaded with 3 mumol/L chelerythrine, application of 1 mumol/L 5-HT failed to enhance ITau. The above results thus indicate that intracellular PKC pathway is at least partially involved in the enhancement of ITau by 5-HT. In accordance with our previous study, it is suggested that 5-HT may play an important antinociceptive function in SDCN through enhanced Gly and Tau inhibitory effects.
Wang
D S
DS
Department of Anatomy and K.K. Leung Brain Research Centre, Fourth Military Medical University, Xi'an 710032.
Xu
T L
TL
Pang
Z P
ZP
Li
J S
JS
D000818:Animals; D004594:Electrophysiology; D009474:Neurons / Q000502:physiology; D009619:Nociceptors / Q000187:drug effects*; D009761:Nystatin; D018408:Patch-Clamp Techniques / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012701:Serotonin / Q000494:pharmacology*; D013116:Spinal Cord / Q000502:physiology*; D013654:Taurine / Q000494:pharmacology*
D009761:Nystatin; D013654:Taurine; D012701:Serotonin