INFLUENCE OF L-ARGININE ON AUTONOMIC-CARDIOVASCULAR FUNCTION IN AGING HUMANS

这个子项目是利用由NIH/NCRR资助的中心拨款提供的资源的许多研究子项目之一。子项目和调查员(PI)可能从另一个NIH来源获得了主要资金，因此可能会出现在其他CRISE条目中。列出的机构是针对中心的，而不一定是针对调查员的机构。随着年龄的增长，心血管(心脏和血管)和神经系统会发生一些不利的变化。这些变化背后的机制(生物学原因)尚不清楚。然而，我们知道：a)紧张性一氧化氮(NO)生物利用度降低可引起与某些心血管疾病患者相似的不良变化；b)紧张性NO生物利用度随年龄增长而降低。此外，我们还知道，定期的有氧运动与心血管和神经系统功能的改善以及更好的补药和生物利用度有关。因此，这项拟议的研究将检验这样一个假设，即随着年龄的增长，心血管和神经系统功能的不利变化部分是由于紧张性NO生物利用度的降低，而与定期运动相关的更理想的功能是由于更多的NO产生。这将通过在年轻人和老年人久坐不动的男性和女性身上注射NO前体(L-精氨酸)，并在耐力运动中训练老年人，同时测量给药前后的心血管和神经系统功能来确定这一点。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. A number of adverse changes occur to the cardiovascular (heart and blood vessels) and nervous systems with advancing age. The mechanisms (biological reasons) underlying these changes are unknown. However, we do know that: a) decreased tonic nitric oxide (NO) bioavailability can cause similar adverse changes that can be observed in patients with certain cardiovascular diseases; and b) tonic NO bioavailability decreases with advancing age. In addition, we also know that regular aerobic exercise is associated with improved cardiovascular and nervous system function as well as greater tonic NO bioavailability. Accordingly, the proposed research will test the hypothesis that the adverse changes in cardiovascular and nervous system funcion with aging is due, in part by, decreased tonic NO bioavailability, whereas the more optimal function associated with regular exercise is due to greater NO production. This will be determined by administering the precursor to NO (L-Arginine) in young and older sedentary men and women, and in endurance exercise trained older adults while measuring cardiovascular and nervous system functions before and after this administration.