title: Developmental changes in rhythmic spinal neuronal activity in the rat fetus.
abstract: In the developing rat spinal cord, formation and differentiation of the central pattern generator for locomotion occur during the prenatal period. Early on, excitatory synaptic transmission mediated by glycine receptors plays a leading role for rhythmogenesis, at a later stage, followed by glutamate-receptor-mediated synaptic transmission becoming dominant. The maturation of inhibitory circuitry in the spinal cord, mediated largely by glycinergic synapses, is crucial for the generation of alternating activity between left/right limbs and flexor/extensor muscles. Formation of left/right alternation is presumably due to developmental changes in the properties of the postsynaptic neurons, themselves, whereas flexor/extensor alternation requires the additional emergence of inhibitory synaptic functions in the spinal cord.
authors.affiliation: Department of Physiology, Institute of Basic Medical Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8575, Japan. kudo@md.tsukuba.ac.jp
authors.forename: Norio
authors.initials: N
authors.lastname: Kudo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nishimaru
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Nakayama
mesh_terms: D000818:Animals; D005314:Embryonic and Fetal Development; D005324:Fetal Movement / Q000502:physiology; D005333:Fetus / Q000166:cytology / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D010507:Periodicity; D051381:Rats / Q000196:embryology*; D013116:Spinal Cord / Q000196:embryology*