Objective To observe the antifebrile effect of Naoreqing (NRQ) oral liquid on secretive function of vaso-endothelial cells
in rabbits with
endotoxic fever. Methods Endotoxic fever rabbit model was duplicated to observe the effects of NRQ on body temperature, blood levels of thromboxane B_2 (TXB_2), 6-keto-prostaglandin F_ 1α (6-keto-PGF_ 1α) and endothelin (ET) using radioimmunoassay, as well as activity of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) in plasma by chromophoric substrate assay. Results Comparisons of various indexes between the two groups showed significantly difference, i.e. the maximal increment of body temperature: 0.69±0.07℃ vs 1.31±0.13℃ (the NRQ treated group vs the untreated model group, the same hereafter); 2h thermal response index TRI_2 4.85±0.57 vs 8.44±0.98; plasma ET content 197.96±39.11 ng/L vs 250.80±40.99 ng/L; TXB_2 content 177.35±77.30ng/L vs 279.64±83.74 ng/L; activity of PAI 0.84±0.01AU/ml vs 0.86±0.01 AU/ml; plasma 6-keto-PGF_ 1α content 986.70±327.36 ng/L vs 507.81±170.01 ng/L; activity of t-PA 0.25±0.02 IU/ml vs 0.21±0.02 IU/ml (P<0.05,P<0.01). Conclusion NRQ may improve secretive function of vaso-endothelial cells to dilate blood vessel and quicken heat dissipation through body surface, so as to play an integral antipyretic effect in rabbits with endotoxic fever.