Intrinsic firing properties of developing rat superficial dorsal horn neurons.
Neonatal superficial dorsal horn neurons exhibit distinct firing properties in response to nociceptive and tactile inputs, but it is not known whether the intrinsic membrane excitability of these neurons changes during the early postnatal period. We have investigated the evoked firing properties of dorsal horn cells in rat spinal cord slices at different postnatal ages (P3, P10 and P21) and found no significant differences in mean firing frequency, spike frequency adaptation, regularity of action potential discharge or rheobase current levels between age groups. These results demonstrate that the intrinsic excitability of superficial dorsal horn neurons remains stable during early postnatal development and suggest that alterations in the synaptic inputs to these cells explain the changes in response to peripheral stimulation.
Baccei
Mark L
ML
Department of Anatomy and Developmental Biology, University College London, London WC1E 6BT, UK. m.baccei@ucl.ac.uk
Fitzgerald
Maria
M
D000200:Action Potentials / Q000502:physiology* / Q000528:radiation effects; D000375:Aging / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D000831:Animals, Newborn; D004307:Dose-Response Relationship, Radiation; D004558:Electric Stimulation / Q000379:methods; D066298:In Vitro Techniques; D018408:Patch-Clamp Techniques / Q000379:methods; D020671:Posterior Horn Cells / Q000254:growth & development / Q000502:physiology* / Q000528:radiation effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000166:cytology / Q000254:growth & development*