logosm.gif (1133 bytes) PANEL OF BEHAVIORAL ASSAYS

THERMAL PAW SENSITIVITY TEST

The complete description of this test can be found in: Jevtovic-Todorovic, V., Wozniak, D.F., Powell, S., Nardi, A., and Olney, J.W. (1998) Clonidine potentiates the neuropathic pain-relieving action of MK-801 while preventing its neurotoxic and hyperactivity side effects. Brain Research, 781, 202-211.

The thermal paw apparatus is described in detail in:  Hargreaves, K., Dubner, R., Brown, F., Flores, C., and Joris, J. (1988) A new and sensitive method for measuring thermal nociception in cutaneous hyperalgesia. Pain, 32, 77-88.

Apparatus and materials: Clear Plexiglas chambers 10 cm wide x 12.5 cm long x 15 cm tall (often 6-8 of these chambers are used at a time), clear sheet of temperature regulated glass (maintained at 30o C), radiant heat source (focused beam of light) mounted on portable holder beneath glass sheet (this holder is equipped with a mirror to visualize the plantar surface of the hind paw and a photosensor to detect movement (withdrawal) of the foot which is attached to a timer), 70% ETOH

Procedure:
1. Clean chamber and glass sheet with 70% ETOH.
2. Turn on lights in testing room.
3. Place mice on cart outside of testing room.
4. Place mouse into each holding chamber.
5. Allow animals 15 min 1 hour to acclimate to chamber.
6. Position heat source holder beneath plantar surface of paw.
7. Deliver thermal stimulus to paw, which starts timer as well.
8. Record latency to withdraw foot (see timer).
9. The withdrawal reflex is a distinct lifting of the foot from the heat source; if the animal is simply ambulating or if the foot moves for some other reason, do not record the time.
10. Move onto next mouse and test all other mice on apparatus.
11. Once all of the mice have been tested, start over again by testing withdrawal response from opposite foot.
12. Once step 11 is completed, repeat sequence of steps 6-10 for each mouse; there should be two scores for each hindpaw for each mouse.
13. Thermal source should be automatically discontinued if the mouse fails to withdraw its foot within 20 seconds (in order to avoid any potential tissue injury).


<BACK>

ABC Home  |  Procedures  |  Helpful Hints  |  How to Begin  |  Prices  |  Policies   |  People
WUSM  |  WUNI  |   Other WUSM Cores