Elucidation of mechanisms for protective effects of NO-generating agents against radiation

在治疗心绞痛和高血压的药物中，选择硝普钠、硝酸异山梨酯、硝酸甘油、尼可地尔、尼普拉地尔，并使用正常人成纤维细胞AG 1522检测其对X射线诱导的损伤和毒性的保护活性。用正常小鼠（jcl：ICR，8周龄，雄性）对50种药物进行了X射线、γ射线和中子混合辐射或中子辐射损伤的防护作用和毒性试验。所有药物均无毒性反应。而硝普钠仅对X射线损伤具有保护作用，其机制可能与促进造血和免疫功能的恢复有关。硝普钠对混合辐射所致的损伤有保护作用，但对单纯中子辐射所致的损伤无保护作用。

Among the drugs for angina pectoris and hyperpiesia, sodium nitroprusside, isosorbide dinitrate, nitroglycerin, nicorandil, nipradilol were selected and examined for the presence of protective activities against X-rays-induced injury and toxicities using normal human fibroblasts, AG1522cells. All drugs possessed protective activities against radiation and indicated non-toxicities up to 3μM.Furthermore, 5drugs were examined for the presence of protective activities against X-rays, mixed radiation(γ-rays and neutron) or neutron-induced injury and toxicities using normal mice(jcl : ICR, 8weeks old, male). All drugs were non-toxicities. However, Sodium nitroprusside only possessed protective activities against the injury induced by X-rays and it is due to promoting of restoration of hematopoietic and immune functions. Sodium nitroprusside was effective in the injury induced by mixed radiation, but not by neutrons alone.