Summary
Using the mechanoreceptors in the cat's sinus hair follicles as a model system the recent hypothesis (Hartschuh and Weihe 1980) was tested that Merkel cells are mechanoreceptive sensory cells releasing met-enkephalin as a neurotransmitter to initiate action potentials in the terminals of type I afferent fibres. Since the met-enkephaline antagonist naloxone, even in high doses, did not affect responses in any type I mechanosensitive afferent it is unlikely that a synaptic mechanism with the release of met-enkephalin underlies impulse generation in Merkel cell-axon complexes, nor did naloxone influence the responses from other types of mechanoreceptors.
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Financially supported by Sonderforschungsbereich 33
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Gottschaldt, K.M., Vahle-Hinz, C. Evidence against transmitter function of met-enkephalin and chemosynaptic impulse generation in “Merkel cell” mechanoreceptors. Exp Brain Res 45, 459–463 (1982). https://doi.org/10.1007/BF01208608
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DOI: https://doi.org/10.1007/BF01208608