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Formalin evokes calcium transients from the endoplasmatic reticulum.

ABSTRACT: The formalin test is the most widely used behavioral screening test for analgesic compounds. The cellular mechanism of action of formaldehyde, inducing a typically biphasic pain-related behavior in rodents is addressed in this study. The chemoreceptor channel TRPA1 was suggested as primary transducer, but the high concentrations used in the formalin test elicit a similar response in TRPA1 wildtype and knockout animals. Here we show that formaldehyde evokes a dose-dependent calcium release from intracellular stores in mouse sensory neurons and primary keratinocytes as well as in non-neuronal cell lines, and independent of TRPA1. The source of calcium is the endoplasmatic reticulum and inhibition of the sarco/endoplasmic reticulum calcium-ATPase has a major contribution. This TRPA1-independent mechanism may underlie formaldehyde-induced pan-neuronal excitation and subsequent inflammation.

SUBMITTER: Fischer MJ

PROVIDER: S-EPMC4398422 | biostudies-literature | 2015

REPOSITORIES: biostudies-literature

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Formalin evokes calcium transients from the endoplasmatic reticulum.

Fischer Michael J M MJ Soller Kailey J KJ Sauer Susanne K SK Kalucka Joanna J Veglia Gianluigi G Reeh Peter W PW

PloS one 20150415 4

The formalin test is the most widely used behavioral screening test for analgesic compounds. The cellular mechanism of action of formaldehyde, inducing a typically biphasic pain-related behavior in rodents is addressed in this study. The chemoreceptor channel TRPA1 was suggested as primary transducer, but the high concentrations used in the formalin test elicit a similar response in TRPA1 wildtype and knockout animals. Here we show that formaldehyde evokes a dose-dependent calcium release from i ...[more]

PMID: 25875358

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