L-赖氨酸锌配合物致惊厥实验研究

为观察L－赖氨酸锌配合物是否具有致惊厥作用,选出了阈下剂量的化学致惊剂和电刺激强度,用小鼠进行了实验研究,结果表明,L－赖氨酸锌配合物无明显增强阈下剂量回苏灵和阈下电刺激小鼠致惊厥作用。     

小鼠肝脏和肌肉在甘油和二甲亚砜中经不同温度冷冻后的耗氧量

本文用氧电极技术测定小鼠肝脏和肌肉组织的耗氧量.将组织放置在台氏液,10%甘油台氏液或二甲亚砜台氏液内,降温到0℃,-20℃,-40℃及-196℃后,迅速在40℃水浴内复温,然后分别测定冷冻前后的耗氧量.实验结果表明,不加冷冻保护剂的肝脏或肌肉组织经过冷冻处理后,呼吸强度随温度的降低而减少.在-20℃时急骤降低,肝脏只有对照组的51%,肌肉为22%.添加冷冻保护剂的冷冻各组,都比不加保护剂的耗氧量要高. 二甲亚砜保护小鼠肝脏和肌肉组织的代谢活力要比甘油在同样条件下为优. 尤其在细胞低温致死的危险温度区域时更为明显.     

Acute effects of orally administered sodium arsenate on heme biosynthetic enzymes in the tissues of three strains of mice

Sodium arsenate (Na₂HASO₄· 7H₂O, As(V)) was administered to three genetically different strains of mice, ICR, C57BL/6J and DBA/2J, in a single oral dose of 54 mg kg⁻¹ body weight. The effects on the activities of heme biosynthetic enzymes in the spleen, liver, kidney and peripheral blood were investigated. The activities of δ‐aminolevulinate synthase (ALAS, EC 2.3.1.37), catalyzing the first reaction in the heme biosynthetic pathway and the rate‐limiting enzyme for heme synthesis, δ‐aminolevuilinate dehydratase (ALAD, EC 4.2.1.24) and porphobilinogen de‐­aminase (PBGD, EC 4.3.1.8) in the spleens of the ICR strain, were remarkably reduced to 51%, 32% and 42%, respectively, in comparison with each mean value of the control group. In contrast, these activities were significantly increased in the livers of the C57BL/6J strain, and a similar trend was observed in the DBA/2J strain. In the kidneys, the ALAD activity was significantly reduced in the ICR strain, but no significant differences in the other two strains were found. These results suggest that the influence of As(V) on the activity of heme biosynthetic enzymes is most potently manifested in the spleen tissue of the ICR strain. Copyright­© 1999 John Wiley & Sons, Ltd.