OBJECTIVETo explore the effect of titanium dioxide (TiO₂) nanoparticles on hemogram in rats with gastric ulcer.

METHODSPhysicochemical properties of TiO₂ nanoparticles were characterized. Twenty-four clear class SD male rats, aging 8 week-old, were randomly divided into 4 groups, 6 rats for each group. 20% acetic acid were injected into the rats' stomach on the border of gastric body and pyloric antrum, and hereby established the gastric ulcer model. The rats in 4 groups were exposed to TiO₂ nanoparticles through intragastric administration at 0, 10, 50 and 200 mg/kg body weight respectively for 30 days. Afterwards, the rats were conducted blood routine test and blood coagulation test for analysis.

RESULTSTiO₂ nanoparticles were anatase crystals, closely spherical shape, whose average grain diameter was (75 ± 15) nm. The levels of white blood cell (WBC) count ((8.48 ± 3.28)×10⁹/L), lymphocyte (LYM) ((6.85 ± 2.53)×10⁹/L), monocyte (MOD) ((0.27 ± 0.12)×10⁹/L), granulocyte (GRN) ((1.37 ± 0.86)×10⁹/L), red blood cell (RBC) ((8.20 ± 0.49)×10⁹/L) and hematocrit (HCT) ((45.3 ± 1.4)%) in the 200 mg/kg dose group were significantly higher than those in the control group ((2.63 ± 0.34)×10⁹/L, (2.25 ± 0.26)×10⁹/L, (0.05 ± 0.06)×10⁹/L, (0.33 ± 0.26)× 10⁹/L, (4.87 ± 2.37)×10⁹/L and (27.2 ± 13.3)%, respectively; t values were -3.449, -3.825, -3.554, -3.097, -2.972 and -2.936 respectively, P values all < 0.05). The levels of WBC ((6.88 ± 3.06)×10⁹/L), MOD ((0.20 ± 0.07)×10⁹/L), RBC ((7.79 ± 0.48)×10⁹/L) and HCT ((42.7 ± 2.8)%) in 50 mg/kg dose group were also statistically higher than those in the control group (t values were -2.507, -2.367, -2.605 and -2.511 respectively, all P values < 0.05). There was no statistically difference found in other blood routine index and coagulation index between the three experimental groups and control group.

CONCLUSIONThe long term intake of TiO₂ nanoparticles caused a statistically increase in the amount of WBC and RBC in rats with gastric ulcer; however, there was no obvious changes found in blood platelet and coagulation index.