Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Bethesda, MD: American Society for Pharmacology and Experimental Therapeutics
Erscheinungsjahr
1993
Link zum Volltext
Quelle
MEDLINE
Beschreibungen/Notizen
Glutamate-mediated neurotransmission occurs through the activation of multimeric postsynaptic receptors. One mechanism by
which functional diversity of glutamate responsiveness may occur is by a single cell expressing multiple receptors containing
different subunits. In a direct test of this hypothesis, we examined the glutamate receptor subunit mRNA composition of several
individual CA1 neurons in hippocampal slices. Experiments used amplified antisense RNA coupled with expression profiling and
polymerase chain reaction amplification to identify and determine the relative amounts of subunit mRNAs co-localized in single
cells. The results demonstrate that each CA1 neuron contains varying amounts of most glutamate receptor mRNAs. In addition
to relative mRNA levels, the single-cell approach also highlighted other possible sources of receptor diversity. This included
the existence of novel, alternatively spliced forms of the N-methyl-D-aspartate receptor type 1 and glutamate-kainate receptor
type 2 subunits. Surprisingly, levels of N-methyl-D-aspartate receptor type 1 mRNA were relatively low, compared with those
of other glutamate receptor mRNAs. One postulated source of potential heterogeneity, RNA editing, was not a general cellular
mechanism. There was no evidence that glutamate receptor type 5 mRNA was edited in any of the cells that were examined. These
data show that individual CA1 neurons, in the intact synaptic network of hippocampal slices, generate glutamate receptor mRNA
diversity in several ways, which together contribute to the diversity of functional receptors observed electrophysiologically.