HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) All Versions of this Article: 546/2/483    most recent 2002.031773v1 Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Momiyama, T. Search for Related Content PubMed PubMed Citation Articles by Momiyama, T.

Parallel decrease in -conotoxin-sensitive transmission and dopamine-induced inhibition at the striatal synapse of developing rats

Toshihiko Momiyama

Whole-cell patch-clamp recordings of GABAergic IPSCs were made from cholinergic interneurones in slices of striatum from developing rats aged 21-60 days postnatal. In addition, the Ca²⁺ channel subtypes involved in synaptic transmission, as well as dopamine (DA)-induced presynaptic inhibition, were investigated pharmacologically with development by bath application of Ca²⁺ channel blockers and DA receptor agonists. The IPSC amplitude was reduced by -conotoxin GVIA (-CgTX) or -agatoxin TK (-Aga-TK) across the whole age range, suggesting that multiple types of Ca²⁺ channels mediate transmission of the synapse. The IPSC fraction reduced by -CgTX significantly decreased, whereas that reduced by -Aga-TK remained unchanged with development. DA or quinpirole, a D₂-like receptor agonist, presynaptically reduced the IPSC amplitude throughout development. The DA-induced inhibition decreased with age in parallel with the decrease in N-type Ca²⁺ channels. DA showed no further inhibition of IPSCs after the inhibitory effect of -CgTX had reached steady state throughout development. These results demonstrate that there is a functional link between presynaptic N-type Ca²⁺ channels and D₂-like DA receptors at inhibitory synapses in the striatum. They also demonstrate that the suppression of GABAergic transmission by D₂-like receptors is mediated by modulation of N-type Ca²⁺ channels and decreases in parallel with the developmental decline in the contribution of N-type Ca²⁺ channels to exocytosis.

This article has been cited by other articles:

				T. Momiyama and Y. Fukazawa D1-like dopamine receptors selectively block P/Q-type calcium channels to reduce glutamate release onto cholinergic basal forebrain neurones of immature rats J. Physiol., April 1, 2007; 580(1): 103 - 117. [Abstract] [Full Text] [PDF]

				H. Salgado, F. Tecuapetla, T. Perez-Rosello, A. Perez-Burgos, E. Perez-Garci, E. Galarraga, and J. Bargas A Reconfiguration of CaV2 Ca2+ Channel Current and Its Dopaminergic D2 Modulation in Developing Neostriatal Neurons J Neurophysiol, December 1, 2005; 94(6): 3771 - 3787. [Abstract] [Full Text] [PDF]