Figure 1.

SA in afferent units innervating the affected knee joint after MIA-OA. (A) Preparation design; the L3 dorsal root is teased and resulting bundles are used for recording. (B) Recordings from L3 teased bundles of units with RFs in the knee show increased frequency of SA MIA-OA animals compared to saline-injected controls. (C) MIA-OA animals showed an increased number of units with SA per recorded bundle. (D) MIA-OA increased SA firing rates. (E) Preparation design for L4 dorsal root recording. (F) MIA-OA increases the frequency of SA in L4 dorsal root bundles with knee RFs. (G) No difference in units per recorded bundle with SA was observed in recordings from L4 dorsal root. (H) MIA-OA does not increase SA firing rates in recordings from the L4 dorsal root. (I) Preparation design for recording from the saphenous nerve. (J) MIA-OA increases frequency of SA in recorded bundles. (K) MIA-OA has no effect on SA firing rates in saphenous nerve recordings. (L) Sample trace of recordings from saphenous nerve. Red lines in C, G, K represent median and represent means in D and H. Data are from n=5 rats with saline injection and n=5 rats with injection of MIA for each type of recordings from L3, L4, and saphenous nerve. * P<0.05, ** P<0.01, *** P<0.001 by x² test in B, F, and J, and t-test in all other comparison.