Figure 4.

Distal tail histology. Representative images of distal tail histology demonstrate inflammation scores of 0 (none or minimal; example: day 7, isoflurane-treated mouse with sham biopsy), 1 (mild; example: day 7, Cetacaine-treated mouse with sham biopsy); 2(moderate; example: day 7, mouse treated with ethyl chloride and sham biopsy), and 3 (severe; example: day 7, untreated control mouse with biopsy). Overall, inflammation scores were higher (P = 0.01) in biopsied mice compared with sham mice for as long as 7 d after biopsy. Inflammation scores for the distal portion of the tail were significantly (P < 0.01) higher in mice that received ethyl chloride compared with mice that received Cetacaine, isoflurane, or no anesthesia. Ep, epidermis; NP, nucleus pulposa; VB, vertebral body; magnification, 10× (inset, 40×).