Schrader W P, West C A
Wadsworth Center for Laboratories and Research, New York State Department of Health, Albany 12201-0509.
Circ Res. 1990 Mar;66(3):754-62. doi: 10.1161/01.res.66.3.754.
The distribution of adenosine deaminase and adenosine deaminase complexing protein in rabbit heart has been compared using immunohistochemical staining procedures. Sections (4-5 microns) of tissue fixed in Clarke's solution or paraformaldehyde and embedded in paraffin were stained by the peroxidase anti-peroxidase method for adenosine deaminase or complexing protein, using affinity purified antibodies. Staining for adenosine deaminase and complexing protein was observed in the central myocardium of all heart chambers. Adenosine deaminase was detected in endothelial cells of blood vessels and adjacent pericytes. The nuclei of arteries stained heavily for adenosine deaminase, whereas those of venules and small veins, although positive, stained much more lightly. The cytoplasm of blood vessel endothelial cells and smooth muscle cells of the tunica media were also weakly positive for adenosine deaminase. Endothelial cells of the endocardium and epicardium did not stain. Randomly distributed mononuclear inflammatory cells and interstitial connective tissue fibroblasts were also negative for adenosine deaminase. These results raise the possibility that endothelial cells containing adenosine deaminase could serve as a metabolic barrier preventing the free exchange of plasma and interstitial adenosine. Positive staining for complexing protein was restricted to blood vessel endothelial cells, especially cytoplasmic processes. Colocalization experiments carried out with biotinylated primary antibodies indicate that some vessels are positive for both adenosine deaminase and complexing protein. This is the first experimental evidence of possible in situ association of adenosine deaminase and complexing protein.
采用免疫组织化学染色方法，比较了兔心脏中腺苷脱氨酶和腺苷脱氨酶复合蛋白的分布情况。使用亲和纯化抗体，通过过氧化物酶抗过氧化物酶法，对固定于克拉克溶液或多聚甲醛中并包埋于石蜡的组织切片（4 - 5微米）进行腺苷脱氨酶或复合蛋白染色。在所有心腔的中心心肌中均观察到腺苷脱氨酶和复合蛋白染色。在血管内皮细胞及相邻周细胞中检测到腺苷脱氨酶。动脉细胞核对腺苷脱氨酶染色较重，而小静脉和小静脉的核虽然呈阳性，但染色要淡得多。血管内皮细胞的细胞质和中膜平滑肌细胞对腺苷脱氨酶也呈弱阳性。心内膜和心外膜的内皮细胞不着色。随机分布的单核炎性细胞和间质结缔组织成纤维细胞对腺苷脱氨酶也呈阴性。这些结果提示，含有腺苷脱氨酶的内皮细胞可能作为一种代谢屏障，阻止血浆和间质腺苷的自由交换。复合蛋白的阳性染色仅限于血管内皮细胞，尤其是细胞质突起。用生物素化一抗进行的共定位实验表明，一些血管对腺苷脱氨酶和复合蛋白均呈阳性。这是腺苷脱氨酶和复合蛋白可能在原位结合的首个实验证据。
