Ari Koivisto

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Alpha2-adrenergic receptors (alpha2-adrenoceptors) mediate various physiological actions of endogenous catecholamines in the central and peripheral nervous systems being involved in alertness, heart rate regulation, vasomotor control and nociceptive processing. In the present study, the pharmacological profile of a novel alpha2-adrenoceptor agonist,(More)
The transient receptor potential ankyrin 1 (TRPA1) ion channel is expressed on nociceptive primary afferent neurons. On the proximal nerve ending within the spinal dorsal horn, TRPA1 regulates transmission to spinal interneurons, and thereby pain hypersensitivity. Here we assessed whether the contribution of the spinal TRPA1 channel to pain hypersensitivity(More)
Peripheral diabetic neuropathy (PDN) is a devastating complication of diabetes mellitus (DM). Here we test the hypothesis that the transient receptor potential ankyrin 1 (TRPA1) ion channel on primary afferent nerve fibers is involved in the pathogenesis of PDN, due to sustained activation by reactive compounds generated in DM. DM was induced by(More)
We have used patch-clamp techniques to study the effect of the sulfhydryl group oxidizing agents mercury and thimerosal on calcium-activated nonselective cation channels from brown adipose tissue. 100 nmol/l mercury and 50 μmol/l thimerosal induced a complete block. Blockade could be reversed by reduction of the mercaptide by dithiotreitol (DTT). Mercury(More)
BACKGROUND The TRPA1 ion channel modulates excitability of nociceptors, and it may be activated by compounds resulting from oxidative insults. Diabetes mellitus produces oxidative stress and sensory neuropathy. The authors tested the hypothesis that diabetes-induced endogenous compounds acting on the TRPA1 ion channel contribute to development and(More)
Previous results indicate that intaperitoneal administration of a TRPA1 channel antagonist attenuates diabetic hypersensitivity. We studied whether the antihypersensitivity effect induced by a TRPA1 channel antagonist in diabetic animals is explained by action on the TRPA1 channel in the skin, the spinal cord, or both. For comparison, we determined the(More)
BACKGROUND The transient receptor potential ankyrin 1 (TRPA1) ion channel is expressed on nociceptive primary afferent nerve fibers. On the distal ending, it is involved in transduction of noxious stimuli, and on the proximal ending (within the spinal dorsal horn), it regulates transmission of nociceptive signals. Here we studied whether the cutaneous or(More)
The transient receptor potential ankyrin 1 (TRPA1) ion channel on peripheral terminals of nociceptive primary afferent nerve fibres contributes to the transduction of noxious stimuli to electrical signals, while on central endings in the spinal dorsal horn, it amplifies transmission to spinal interneurons and projection neurons. The centrally propagating(More)
In the spinal dorsal horn, TRPA1 ion channels on central terminals of peptidergic primary afferent nerve fibers regulate transmission to glutamatergic and GABAergic interneurons. Here we determine the cutaneous anti-inflammatory effect of a spinally administered TRPA1 channel antagonist to test the hypothesis that spinal TRPA1 channels contribute to(More)