Comparative effects of various stressors on immunoreactive versus bioactive prolactin release in old and young male rats.
Comparative effects of various stressors on immunoreactive versus bioactive prolactin release in old and young male rats.
复制标题
各种应激源对老年和年轻雄性大鼠免疫反应性与生物活性催乳素释放的比较影响。
DOI：
10.1159/000125402
复制
发表时间：
1990
影响因子：
4.1
通讯作者：
Sylvester,PW
中科院分区：
文献类型：
--
作者：
Briski,KP;Sylvester,PW
Nb 2大鼠淋巴瘤细胞催乳素（PRL）生物测定，结合标准放射免疫测定技术，检查血浆生物活性（生物）和免疫反应性（IR）PRL水平在3至5个月和22至24个月大的雄性Copenhagen-Fischer 344大鼠的各种应激源的影响。在实验前24-48小时，将动物植入慢性心内静脉插管。在暴露于15 min束缚应激、15 min闪光灯应激或2 min乙醚应激之前、期间和之后采集系列血液样品。在2的3项研究中，基础预应力irPRL水平显着较高的老年人相比，年轻的雄性大鼠。然而，在所有研究中，老年动物的基础bioPRL水平显著较低。暴露于约束，频闪灯或乙醚应力诱导血浆IR和bioPRL水平在年轻大鼠的显着和平行的增加，这些应激因素并没有影响血液生物/irPRL的比例。暴露于相同应激源的老年大鼠显示出类似的血浆irPRL增加，但bioPRL释放显着减弱，血浆bio/irPRL水平的比值显着低于年轻大鼠。与此相反，乙醚应力诱导类似的增加，血浆IR和bioPRL水平在两个年龄组和恢复的比例，血浆生物/irPRL水平在老年大鼠的年轻动物。这些结果表明，尽管具有显著更高的基础血浆irPRL水平，但与年轻雄性大鼠相比，该激素的生物活性在老年大鼠中显著降低。这些结果还表明，虽然各种应激源诱导irPRL类似的增加，但它们对年轻和老年大鼠的bioPRL循环水平有不同的影响。这些发现表明，在衰老过程中，PRL的生物合成、加工和/或释放发生了质的变化，这显著降低了这种激素在基础条件下分泌和响应某些类型的应激时的生物效价。
The Nb2rat lymphoma cell prolactin (PRL) bioassay was used, in conjunction with standard radioimmunoassay techniques, to examine the effects of various stressors on plasma bioactive (bio) and immunoreactive (ir) PRL levels in 3- to 5- and 22- to 24-month-old male Copenhagen-Fischer 344 rats. The animals were implanted with chronic intracardiac venous cannulas 24–48 h prior to experimentation. Serial blood samples were taken prior to, during and after exposure to either 15 min restraint stress, 15 min strobe light stress or 2 min ether stress. In 2 of 3 studies, basal prestress irPRL levels were significantly higher in old as compared to young male rats. However, in all studies, basal bioPRL levels were significantly lower in the older animals. Exposure to restraint, strobe light or ether stress induced significant and parallel increases in plasma ir- and bioPRL levels in young rats, and these stressors did not affect the ratio of blood bio/irPRL. Old rats exposed to the same stressors displayed similar increases in plasma irPRL, but bioPRL release was significantly attenuated and the ratio of plasma bio/irPRL levels was significantly lower when compared to young rats. In contrast, ether stress induced similar increases in plasma ir- and bioPRL levels in both age groups and restored the ratio of plasma bio/irPRL levels in old rats to that of young animals. These results demonstrate that, despite having significantly higher basal plasma irPRL levels, the bioactivity of this hormone is significantly diminished in old as compared to young male rats. These results also demonstrate that, although various stressors induce similar increases in irPRL, they have differential effects on the circulating levels of bioPRL in young and old rats. These findings suggest that during the aging process qualitative changes occur in PRL biosynthesis, processing and/or release, which significantly reduces the biopotency of this hormone when secreted during basal conditions and in response to certain types of stress.