ディーゼル排出ガスの肺代謝におよぼす影響 (急性効果) について

抄録

The use of diesel engines has increased greatly in recent years. Diesel engines provide the power for most large trucks, trains and construction and farm machinery. Due to the greater efficiency of fuel utilization of diesel powered vehicles, this trend will probably continue. Although many of the pollutants emitted by diesel engines have been studied, the toxicological effects of complete exhaust have not been elucidated yet.
In the present investigation we tried to elucidate the acute effect of diesel-engine exhaust gas on pulmonary metabolic functions in rats. Rats were exposed to diesel-engine exhaust gas for 96-120 hours, and ED₅₀ of acetylcholine in isolated tracheal strips, activation or inactivation of vasoactive substances through isolated perfused lung lobes and change of plasma levels of serotonin, histamine and thromboxane B₂ (TXB₂) were examined. Rats were classified into three groups, i.e. control group, filtered exhaust gas (F.E.G.) group and exhaust gas (E.G.) group.
1) Fifty percent effective doses of acetylcholine in rat tracheal strips did not show any significant differences among these three groups.
2) Percent inactivation of prostaglandin F_2α (PGF_2α) and PGE₂ through isolated perfused lung lobes in E.G. and F.E.G. groups showed a significant decrease compared with that of control group.
3) Percent inactivation of serotonin and activation of angiotensin I through isolated perfused lung lobes did not show any significant differences among these three groups.
4) Plasma levels of serotonin, histamine and TxB₂ did not show any significant differences among these three groups.
The above results suggest that short term exposure to diesel-engine exhaust gas may affect pulmonary metabolic functions.