Number of BrdU-positive cells in the DG in different experimental groups (see table under the abscissa;+done, - not done).

<p>(A) Overview and (B) magnified detail (red square) of a 40 µm thick coronal section through the DG 42 days after the first BrdU-injection. BrdU-positive cells are labelled dark brown. (C) The NC group (n = 7) and the CXray group (n = 7) were not significantly different, and the AIA group (n = 7) did not differ from the IC group (n = 10). Both the AIA and the IC group had significantly increased numbers of BrdU-positive cells compared to the NC and CXray groups. The column on the right shows another group of 3 rats which were only immunized but not tested for pain-related or locomotor behavior (IC-wt). This group did not significantly differ from the IC group. Data are presented as means ± SEM. **p<0.01; ***p<0.001.</p

Radiovideographic analysis of locomotion in arthritic and immunized control animals.

<p>(A) Walking sequence (top to bottom) of a representative animal of the AIA-group on day 1 after induction of AIA. Arrows show the inflamed knee joint in relieving posture (hardly any change in the joint angle during walking). (B) Range of motion in the inflamed (left side) and non-inflamed (right side) knee joint during the time course of 14 days in a representative animal of the AIA-group (filled symbols) and one animal of the immunized control group (IC, open symbols). BL - baseline.</p

Lack of correlation between swelling or nociceptive behavior and the total number of BrdU-positive cells in the DG in immunized controls (IC) and AIA rats.

<p>Each circle and dot shows the maximal swelling or pain behavior of an individual rat during the observation period of 42 days. Circles: animals just immunized (IC group), Dots: animals with AIA. (A) Maximum joint swelling versus total BrdU-positive cells. (B) Maximum primary hyperalgesia (minimum mechanical threshold) at the inflamed knee joint versus total BrdU-positive cells. (C) Maximum asymmetry (least force on the inflamed hindlimb) between left and right hindlimb versus total BrdU-positive cells.</p

Percentage of BrdU/NeuN-double-positive cells in the DG in different experimental groups (display as in Figure 4).

<p>Thirty BrdU-positive cells of each animal were analyzed for coexpression of NeuN. (A) Confocal images of an immunofluorescent-labelled section of the DG. NeuN-labelled cells are green and BrdU-positive cells are red. In the merged picture (lowest one) arrows show BrdU-NeuN-double-positive cells. (B) There were no significant differences between the NC and the CXray group (p<i> = </i>1.000) and between the AIA and IC group (p<i> = </i>0.476). AIA group showed a significantly increased percentage of mature neurons compared to NC and CXray group. Data are presented as means ± SEM. *p<0.05; **p<0.01.</p

Swelling and pain-related behavior in the AIA and IC groups.

<p>(A) Joint swelling displayed as delta (Δ) between ipsilateral (inflamed) and contralateral (noninflamed) knee joints during the observation period of 42 days. (B) Primary mechanical hyperalgesia assessed by measuring the withdrawal threshold to pressure applied to the knee. (C) Weight bearing of the rats shown as the relative body weight resting on the inflamed hindlimb. Data are presented as means ± SEM. *p<0.05; **p<0.01; ***p<0.001. BL - baseline.</p

Experimental protocol of the study.

<p>BrdU - bromodeoxyuridine.</p