Development of chemosensitivity of an identified insect interneurone

摘要: Characteristic features of cockroach embryos (Periplaneta americana) are determined for different stages in development. Morphological changes giant interneurone 2 (GI 2) the terminal abdominal ganglion during embryogenesis described based on cobalt injections. A sequential proliferation branches preceded by filopodial extension is observed between 45 and 80% embryogenesis, which time characteristic arborization first instar cell established. The cholinergic agonist carbamylcholine was ionophoretically applied to body dendritic region GI at various development, responses were recorded intracellularly. Chemosensitivity appears 40 45% a similar degree both dendrites. sensitivity these areas subsequently diverges, after 60 65% stage, dendrites approximately 1000 times more sensitive than body. At 80 85% there temporary peak sensitivity, increases postembryonic take place before synaptogenesis, decline stage may be related synaptic maturation.