Effect of IV injection of isolated DVs in rats. (A) Reduction of nociceptive responses. The hot-plate test was used, in which rats were placed in jars warmed to 56°C and latency periods until licking of the paws were measured. Results are depicted as the quotient of reaction times measured after DV infusion to reaction times determined before infusion in each animal. One group of animals received a bolus injection of 5 × 10⁹ DVs (n = 5). The second group received an injection of 5 × 10⁹ sonicated DVs (n = 3). The third group received 6 mg of LMW-DXS IP 45 minutes before injection of 5 × 10⁹ DVs (n = 4). All experiments were performed with the same banked DV pool. DVs provoked a significant increase in latency time (*P < .05 vs control), which was significantly decreased in the presence of LMW-DXS (^oP < .05). Bars represent the mean values with SD. (B-C) Rapid cellular uptake of DVs by mononuclear cells. Paraffin-embedded sections of spleen (B) and lung (C) were stained with H&E. (B) Intracellular accumulation of DVs in the marginal zone (asterisk) containing abundant macrophages (left panel; magnification 252×). This pattern is illustrated in the right panel after polarization at lower magnification (63×). (C) Intravascular accumulation of PMNs (left panel, arrowhead; magnification 252×) containing intracellular DVs (right panel, arrowhead; magnification 630×).