Premium
Dye‐Coupling in the neostriatum of the rat: II. Decreased coupling between neurons during development
Author(s) -
Walsh John P.,
Cepeda Carlos,
Hull Chester D.,
Fisher Robin S.,
Levine Michael S.,
Buchwald Nathaniel A.
Publication year - 1989
Publication title -
synapse
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.809
H-Index - 106
eISSN - 1098-2396
pISSN - 0887-4476
DOI - 10.1002/syn.890040309
Subject(s) - lucifer yellow , intracellular , coupling (piping) , extracellular , neuroscience , stimulation , electrophysiology , synapse , biophysics , chemistry , neurotransmission , gap junction , biology , microbiology and biotechnology , biochemistry , materials science , receptor , metallurgy
Physiological and morphological evidence for coupling between neostriatal neurons was obtained from the developing rat. Intracellular injections of Lucifer Yellow‐CH (LY) were made in rat neostriatal slices to study dye transfer (coupling) between neurons. The incidence of interneuronal coupling was 70% in early postnatal (P) periods and declined gradually to 10% in the adult. The number of neurons filled by a single intracellular injection also declined with age. LY injection into single neurons commonly marked aggregates of 4 to 6 cells in neonates. Single injections never produced more than one coupled pair in P20 or older rats. Neurons in which fast prepotentials (FPPs) could be evoked were consistently found to be dye‐coupled. FPPs were resistant to collision with action potentials generated by intracellular current injection. When chemical synaptic transmission was blocked by Mn 2+ , short‐latency depolarization (SLDs) could be evoked by extracellular stimulation. The SLDs were distinguished from chemical synaptic potentials by their “all or none” nature and by their insensitivity to changes in membrane potential. No SLDs were observed in adult neurons. FPPs and SLDs may be indicators of electrotonic transmission between coupled cells. The high incidence of coupling early in development might reflect intercellular communication that contributes to the differentiation and growth of neostriatal neurons.