The peak ear swelling was recorded at 1 h post challenge and the response was gradually deceased over time.
Animals were killed at the peak of swelling and behavioural changes (3 days) (Wilson et al., 2006; Kelly et al., 2007) and dorsal root ganglia (DRG) removed for immunohistochemical staining for TRPA1.
Peak knee swelling following arthritis induction (day 1, 4.4±0.14 mm) was reduced in AIA+NBQX rats (2.95±0.23 mm, 33% reduction, p<0.001) and at all other time points (p<0.001, figure 3A).
Possibly due to the re-distribution of ions along the depth of the tissue, the cartilage tissue showed a peak of swelling and then slowly reached to equilibrium [ 15].
However, AQP4 expression changes depend on the model used; for example, in the rodent model of transient focal brain ischemia, peaks of swelling and AQP4 expression, particularly the M1 isoform, were observed at 1- and 48-hr after ischemia (Ribeiro Mde et al., 2006; Hirt et al., 2009).
The second flare induced by an intravenous challenge with SCW (typically three weeks later) results in a pronounced onset of paw swelling reaching peak on day 3 after i.v. challenge (flare 2) and resolves over a 5 day period.
The first flare induced by an intra-articular injection of SCW results in mild paw swelling that peaks 24 hrs post sensitization (flare 1) and resolves over 72 hours.
Both groups responded with paw swelling, although the peak at day 5 6 was slightly lower in the NT3-expressing group (Fig 7A).
Taken together, the results from the two treatment studies demonstrated that DTH arthritis can be suppressed by systemic administration of TNFα-blocking biologics whether administration was prophylactic, at the time of DTH-arthritis induction, or therapeutic from day 1 after DTH-arthritis induction, when paw swelling had reached peak level.
The differential scanning calorimetry endothermic peak area and swelling ratios in NaCl solution of the composite hydrogels decrease by the addition of HNTs.
