Reader S C, Daly J R, Robertson W R
J Endocrinol. 1982 Mar;92(3):449-55. doi: 10.1677/joe.0.0920449.
The effect of plasma on the bioactivity of ACTH was investigated with the cytochemical section bioassay. Levels of ACTH in normal human plasma were underestimated if the plasma concentration in the incubation medium exceeded 2% and if the plasma ACTH level was less than 2 ng/l. A retrospective analysis of 250 plasma ACTH assays revealed that the ACTH concentration was consistently underestimated in the 1:100 dilution compared with the 1:1000 dilution, although not to the extent that any assay would be rejected for non-parallelism. The extent of the underestimation increased as the ACTH concentration increased. Guinea-pig adrenal sections responded faster to 1:10 or 1:50 dilutions of human plasma (containing 2 ng ACTH/l) than to either 1:100 or 1:1000 dilutions of that same plasma, or to ACTH (over the range 0.005-5 ng/l)in the absence of plasma. This faster response could also be seen in the absence of plasma by increasing the ACTH concentration above 5 ng/l. It seems that plasma contains factors which potentiate the biological effect of ACTH in the cytochemical assay system.U
采用细胞化学切片生物测定法研究了血浆对促肾上腺皮质激素（ACTH）生物活性的影响。如果孵育培养基中的血浆浓度超过2%，且血浆ACTH水平低于2 ng/l，则会低估正常人血浆中的ACTH水平。对250次血浆ACTH测定的回顾性分析显示，与1:1000稀释度相比，1:100稀释度下的ACTH浓度始终被低估，尽管尚未达到因非平行性而拒绝任何测定的程度。低估程度随着ACTH浓度的增加而增加。豚鼠肾上腺切片对1:10或1:50稀释度的人血浆（含2 ng ACTH/l）的反应比对相同血浆的1:100或1:1000稀释度的反应更快，也比对无血浆情况下的ACTH（0.005 - 5 ng/l范围内）的反应更快。通过将ACTH浓度提高到5 ng/l以上，在无血浆的情况下也能看到这种更快的反应。似乎血浆中含有在细胞化学测定系统中增强ACTH生物学效应的因子。
