Moss I R, Inman J G
Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas 75235-9063.
J Appl Physiol (1985). 1989 May;66(5):2280-6. doi: 10.1152/jappl.1989.66.5.2280.
beta-Endorphin-like immunoreactivity (BELI), containing the biologically active beta-endorphin, its precursor beta-lipotropin (BLP), and deactivated product N-acetyl-beta-endorphin (ABE), were measured by radioimmunoassay in plasma, cerebrospinal fluid (CSF), and in a dorsal medullary slice containing the respiratory-related nucleus tractus solitarius (dmscNTS) of young and older piglets in normoxia and hypoxia. Significant increase with hypoxia occurred in the levels of BLP in the plasma and CSF and of BELI and ABE in the plasma of the young group. In the older group, such increases occurred in ABE levels of the dmscNTS, in BLP and ABE levels of the CSF, and in plasma BELI. Estimated levels of pure beta-endorphin were higher in the CSF of young piglets during both control and hypoxia. With hypoxia, these estimated levels increased significantly in the plasma of the young age group but showed only a borderline increase in the old group. It is possible that higher opioid levels in the CSF of young as compared with older neonates, enhanced by a greater opioid increase in their plasma during hypoxia, may help explain the suppressed respiratory response to hypoxia of the newborn.
采用放射免疫分析法，对常氧和低氧条件下的幼龄和老龄仔猪的血浆、脑脊液（CSF）以及含有与呼吸相关的孤束核（dmscNTS）的延髓背侧切片中的β-内啡肽样免疫反应性（BELI）进行了检测，其中BELI包含生物活性β-内啡肽、其前体β-促脂素（BLP）以及失活产物N-乙酰-β-内啡肽（ABE）。幼龄组血浆和脑脊液中BLP水平以及血浆中BELI和ABE水平在低氧时显著升高。老龄组中，dmscNTS的ABE水平、脑脊液中BLP和ABE水平以及血浆BELI出现了此类升高。在对照和低氧期间，幼龄仔猪脑脊液中纯β-内啡肽的估计水平均较高。低氧时，这些估计水平在幼龄组血浆中显著升高，但在老龄组中仅呈临界升高。与老龄新生儿相比幼龄新生儿脑脊液中阿片样物质水平较高，且低氧时其血浆中阿片样物质增加幅度更大，这可能有助于解释新生儿对低氧的呼吸反应受到抑制的现象。
