抄録
To understand the functional organization of the central nervous system (CNS), it is essential to know how sensory information is processed within the CNS. We have been approaching this topic by following the ontogenetic patterning of neural circuit formation related to the cranial and spinal sensory inputs using multiple-site optical recording techniques with voltage-sensitive dyes. In this study, we surveyed developmental organization of neural networks related the olfactory nerve (N. I) in the embryonic chick forebrain. Stimulation applied to the olfactory nerve elicited excitatory postsynaptic potential (EPSP)-related optical signals in the olfactory bulb from the 7-day old embryonic stage (E7). The EPSP was mediated by glutamate, and NMDA- and non-NMDA-receptor components were identified. In more developed stages, in addition to the responses in the olfactory bulb, another response area was discriminated within the cerebrum, which seemed to correspond to the higher-ordered nucleus of the olfactory pathway. The results suggest that the olfactory pathway is functionally generated at early stages of development when neural networks related to other visceral and general somatic sensory inputs are also in the process of developing. [J Physiol Sci. 2006;56 Suppl:S169]
