When acetone is applied to the mouse��s hindpaw, behavioral responses can be scored according to the magnitude of the response . Here, the scores range from zero to five, with a zero score indicating no response and a five the most severe response, which we observed to be prolonged guarding of the hindpaw. When wildtype mice were subjected to this test, the resulting average score for both paws was 2.260.1 . However, when these animals were given 10 or 20 mg/kg PBMC, their scores decreased to 1.860.1 or 1.460.1, respectively, with every mouse given the lower dose exhibiting a decrease in response score . As the higher PBMC concentration lead to a significant drop in core body temperature during the test period , we cannot exclude the possibility that the observed behaviors are purchase PD-0325901 affected by the hypothermia associated with this dose. Nonetheless, there were significantly reduced cold behaviors with 10 mg/kg PBMC, a dose that did not produce a change in core temperature PF-04217903 biological activity beyond that observed with circadian rhythms , suggesting that the drug altered acute cold sensation. In addition to acute cold sensitivity, TRPM8 has also been reported to be necessary for cold hypersensitivity in both inflammatory and neuropathic pain models . Therefore, we next sought to determine if PBMC could alleviate these symptoms in wildtype animals. First, to confirm that TRPM8 is indeed required for inflammatory cold hypersensitivity we used unilateral intraplantar injections of complete Freund��s adjuvant into the hindpaws of wildtype and TRPM8-/- mice. When CFA was injected into one hindpaw in wildtype mice, the acetone response scores for that paw increased from 2.260.3 before the injection to a peak of 3.560.3 by two days post-injury . No changes were observed in the un-injected contralateral paw . However, in TRPM8-/- mice, CFA injection did not significantly change these responses beyond the reduced behaviors we already observed in TRPM8-/- animals at baseline . These data reaffirm the previous report that CFA-induced cold hypersensitivity is TRPM8-dependent . Similarly, neuropathic pain induced by the chronic constriction injury of the sciatic nerve induces symptoms of cold hypersensitivity which have also been reported to be TRPM8- dependent .