AGE & CONTROL OF CUTAN VASOCONSTRICT SKIN COOLING & REG OF ALPHA 2C RECEPTORS

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。当一个人暴露在寒冷的环境中时，身体通过收缩皮肤中的血管来保存热量。这减少了温暖的血液通过寒冷的皮肤的流动。然而，衰老会降低皮肤血管收缩的能力。这会导致老年人在寒冷的时候皮肤血流量更高，使他们更容易热量流失。这个项目的目的是研究局部皮肤降温引起血管收缩的机制。该项目还将探索衰老如何影响这些机制。本研究的目标是：1)确定局部皮肤降温(“降温的程度和持续时间”)引起的皮肤血管收缩的神经成分(交感和非交感)；2)确定局部降温皮肤的血管收缩反应是否由2C-肾上腺素能受体介导(“A2受体”)；3)研究人类衰老如何影响降温皮肤的血管收缩反应。我们假设，随着降温程度和持续时间的增加，老年人降温皮肤中的血管收缩作用将日益减弱。我们还假设A2C肾上腺素能受体参与对局部降温的血管收缩反应，但这种反应在老年人中是迟钝的。

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. When a person is exposed to a cold environment, the body conserves heat by constricting blood vessels in the skin. This reduces the flow of warm blood through cold skin. However, aging reduces the ability of the skin's blood vessels to constrict. This causes older individuals to have a higher skin blood flow in the cold and makes them more vulnerable to heat loss. The purpose of this project is to examine the mechanisms responsible for vasoconstriction induced by local cooling of the skin. The project will also explore how aging affects those mechanisms. The goals of this study are to 1) characterize the neural components (sympathetic vs. non-sympathetic) of skin blood vessel constriction in response to localized skin cooling ("Degree and duration of cooling"), 2) determine whether a2C-adrenergic receptors mediate vasoconstriction in locally cooled skin ("a2 Receptors"), and 3) investigate how human aging affects the vasoconstriction response in cooled skin. We hypothesize that vasoconstriction in cooled skin will be increasingly attenuated in older people as the degree and duration of cooling increases. We also hypothesize that the a2C-adrenergic receptors participate in the vasoconstriction response to local cooling, but the response is blunted in older people.