【摘要】 本工作对大鼠肾及小鼠十二指肠等进行了光学显微镜下腺苷环化酶的细胞化学研究;并在大鼠肾、颌下腺及肝等组织进行了电镜细胞化学定位的观察。采用 ATP 和特异性底物AMP-PNP 显示腺苷环化酶的活性。实验结果表明:(1)温育在含有和不含有底物的孵育液中,电镜下均观察到在组织的相同部位呈现出黑色电子密度沉淀,这种沉淀物的出现对戊二醛固定较为敏感。光学显微镜下,经不加底物的孵育液温育的切片均为阴性反应。(2)孵育液内加入腺苷环化酶的激活剂(氟化钠)或抑制剂(四氧嘧啶),其反应沉淀物的出现均无明显变化。(3)在碱性磷酸酶含量较高的组织(肾、十二指肠)中,以 AMP-PNP 为底物,在光学显微镜下观察到有碱性磷酸酶反应的干扰。(4)组织小块或冰冻切片经煮沸加热处理后,在光学显微镜和电镜下均不出现沉淀物。我们的实验结果进一步对 R-H 氏显示腺苷环化酶的细胞化学方法的有效估价表示怀疑。更多还原

【Abstract】 The cytochemical localization of adenylate cyclase in kidney of the rat and duo- denum of the mouse was studied under the light microscope,and the ultracyto- chemical localization of adenyiate cyclase in kidney,submandibular gland and liver of the rat was also investigated under the electron microscope.Adenylate cyclase(AC) activity was demonstrated by using ATP or special substrate AMP-PNP(Adenylyl imidodiphosphate).Our experimental results showed that:(1)Whether the tissue blocks or frozen sections were incubated in the medium with or without the substrate,the black electron dense precipitates by lead ions was formed at the same site of production in tissues observed under electron microscope.Precipitates by lead ions appeared to be quite sensitive after fixation with 1% glutaraldehyde.Bul frozen sections incubated in the medium without substrate showed no enzyme activity and negative reaction under the light microscope.(2)The precipitate after incubation in the presence of fluoride or Alloxan in the basal medium showed no apparent changes.(3)Tissues,such as kidney, duodenum etc,of stronger Alkaline Phosphatase activity tend to interfere with the effective demonstration of AC by using AMP-PNP as the substrate in the incubation media under the light microscope.(4)If tissue blocks or frozen sections were heated before incubation in the complete medium,it resulted an absolute lack of precipitates both in light or electron microscopy. The results of our experiments further raise,the question abóut the validity of using ionic lead to evalute Adenylate Cyclase activity in the Reik-Howell cytochemical method.更多还原