JN Miami Valley Hospital
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
 QUICK SEARCH:   [advanced]


     


J Neurophysiol (July 13, 2005). doi:10.1152/jn.00066.2005
This Article
Right arrow Full Text (PDF)
Right arrow All Versions of this Article:
94/5/3069    most recent
00066.2005v1
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Guatteo, E.
Right arrow Articles by Lipski, J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Guatteo, E.
Right arrow Articles by Lipski, J.
Submitted on January 20, 2005
Accepted on July 13, 2005

Temperature sensitivity of dopaminergic neurons of the substantia nigra pars compacta: involvement of TRP channels

Ezia Guatteo1*, Kenny K. H. Chung1, Tharushini K. Bowala1, Giorgio Bernardi1, Nicola B. Mercuri1, and Janusz Lipski1

1 Experimental Neurology, Fondazione S. Lucia-IRCCS, Rome, Italy

* To whom correspondence should be addressed. E-mail: e.guatteo{at}hsantalucia.it.

Changes in temperature of up to several degrees have been reported in different brain regions during various behaviors or in response to environmental stimuli. We investigated temperature sensitivity of dopaminergic neurons of the rat substantia nigra pars compacta (SNc), an area important for motor and emotional control, using a combination of electrophysiological techniques, microfluorometry and RT-PCR in brain slices. Spontaneous neuron firing, cell membrane potential/currents and intracellular Ca2+ level ([Ca2+]i) were measured during cooling by up to 10° and warming by up to 5° from 34°C. Cooling evoked slowing of firing, cell membrane hyperpolarization, increase in cell input resistance, an outward current under voltage- clamp, and a decrease of [Ca2+]i. Warming induced an increase in firing frequency, a decrease in input resistance, an inward current, and a rise in [Ca2+]i. The cooling-induced current, which reversed in polarity between -5 and -17 mV, was dependent on extracellular Na+. Cooling-induced whole-cell currents and changes in [Ca2+]i were attenuated by 79% in the presence of 2-aminoethoxydiphenylborane (2-APB; 200 µM), and the outward current was reduced by 20% with ruthenium red (100 µM). RT-PCR conducted with tissue punches containing the SNc revealed mRNA expression for TRPV3 and TRPV4 channels, known to be activated in expression systems by temperature changes within the physiological range. 2-APB, a TRPV3 modulator, increased baseline [Ca2+]i, while 4-{alpha}PDD, a TRPV4 agonist, increased spontaneous firing in 7 of 14 neurons tested. We conclude that temperature-gated TRPV3 and TRPV4 cationic channels are expressed in nigral dopaminergic neurons and are constitutively active in brain slices at near physiological temperatures, where they affect the excitability and calcium homeostasis of these neurons.




This article has been cited by other articles:


Home page
J. Neurophysiol.Home page
J. M. Wilson, A. I. Cowan, and R. M. Brownstone
Hb9 Interneurons: Reply to Ziskind-Conhaim and Hinckley
J Neurophysiol, February 1, 2008; 99(2): 1047 - 1049.
[Full Text] [PDF]


Home page
Physiol. Rev.Home page
B. Nilius, G. Owsianik, T. Voets, and J. A. Peters
Transient Receptor Potential Cation Channels in Disease
Physiol Rev, January 1, 2007; 87(1): 165 - 217.
[Abstract] [Full Text] [PDF]


Home page
J. Neurosci.Home page
V. A. Klyachko and C. F. Stevens
Temperature-dependent shift of balance among the components of short-term plasticity in hippocampal synapses.
J. Neurosci., June 28, 2006; 26(26): 6945 - 6957.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Regul. Integr. Comp. Physiol.Home page
S. Kobayashi, A. Hori, K. Matsumura, H. Hosokawa, and J. A. Boulant
Point-Counterpoint: Heat-induced membrane depolarization of hypothalamic neurons: a putative/an unlikely mechanism of central thermosensitivity
Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2006; 290(5): R1479 - R1484.
[Full Text] [PDF]




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH
Visit Other APS Journals Online
Copyright © 2005 by the The American Physiological Society.