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. 1986 Oct;50(4):753–757. doi: 10.1016/S0006-3495(86)83515-9

Step reductions in extracellular Ca2+ activate a transient inward current in chick dorsal root ganglion cells.

J J Hablitz, U Heinemann, H D Lux
PMCID: PMC1329853  PMID: 3779010

Abstract

We investigated whether transient step reductions in divalent cations would produce detectable changes in neuronal excitability similar to those reported in the total absence of divalent cations. Using cultured chick dorsal root ganglion cells as a model system, our results indicate that a step reduction in divalent cations induces a transient inward current. This response is mediated by a tetrodotoxin-resistant, Na+-permeable, cation channel that is blocked by cadmium. This, and our observation that the response is abolished by verapamil, suggests that the current passes through calcium channels. This transient inward current was estimated to be activated by decreases in extracellular calcium ([Ca2+]o) as small as 0.5-0.8 mM and thus represents a different response from the one previously observed when steady-state [Ca2+]o levels were reduced to micromolar levels.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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