6533b850fe1ef96bd12a8361
RESEARCH PRODUCT
Coexpression of heat-evoked and capsaicin-evoked inward currents in acutely dissociated rat dorsal root ganglion neurons.
Timo KirschsteinRolf-detlef TreedeDietrich Büsselbergsubject
Hot TemperaturePatch-Clamp TechniquesCentral nervous systemRats Sprague-Dawley03 medical and health scienceschemistry.chemical_compound0302 clinical medicineDorsal root ganglionGanglia SpinalmedicineAnimalsPatch clamp030304 developmental biologyCell SizeNeurons0303 health sciencesGeneral NeuroscienceReproducibility of ResultsSpinal cordSensory neuronRatsmedicine.anatomical_structureNociceptionnervous systemchemistryCapsaicinNociceptorBiophysicsCapsaicinNeuroscience030217 neurology & neurosurgerydescription
Noxious heat is able to activate heat-sensitive nociceptors in the skin very rapidly, but little is known about the mechanisms by which heat is transduced. We used the whole-cell patch-clamp technique to study the effects of noxious heat and capsaicin on freshly dissociated rat dorsal root ganglion neurons in vitro. Using temperatures between 41 degrees C and 53 degrees C, 8 of 19 small neurons (phior = 30 microm) exhibited a heat-evoked inward current. All heat-sensitive neurons tested were also capsaicin-sensitive. Moreover, the heat response tended to be enhanced after capsaicin (360 +/- 150 pA versus 125 +/- 45 pA, P0.1, n = 7). Two of five heat-insensitive neurons were excited by capsaicin; both neurons developed a heat response after capsaicin. Large neurons (phi30 microm) did not respond to heat (0/7), and were not sensitive to capsaicin either. These findings indicate that heat stimuli may directly activate capsaicin-sensitive primary nociceptive afferents.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1997-08-01 | Neuroscience letters |