Reflex control of the cutaneous vasculature.
Reflex control of the cutaneous vasculature.
复制标题
皮肤脉管系统的反射控制。
DOI：
--
复制
发表时间：
1977
影响因子：
6.5
通讯作者：
L. Rowell
中科院分区：
文献类型：
--
作者：
L. Rowell
皮肤血流的主要功能是调节体温。在其大部分范围内，皮肤血流远远超过皮肤的代谢需求。皮肤的小动脉和静脉主要由丰富的交感肾上腺素能神经支配，特别是在肢端区域。这些紧张性活性的血管收缩神经纤维是（1）主要起源于皮肤温度感受器的温度调节反射，（2）起源于动脉和心肺压力感受器的压力反射，（3）化学感受器反射和（4）对直立姿势和运动的反射反应的传出臂。人类的皮肤血管系统可能是独一无二的，因为它的范围很大，对这些反射驱动的反应性很高。人类皮肤也是独特的，具有神经源性血管扩张系统，该系统是起源于中枢温度感受器的反射的主要传出臂。显然，这个系统只参与体温调节反射;它的发射器仍然未知;它控制全身和大部分皮肤的血液流动。在人类和狒狒中，中心温度每变化一度（C°），皮肤血流的反射性变化大约是皮肤温度变化产生的反射性变化的20倍。然而，在狒狒和其他物种中，皮肤血管系统似乎主要是肾上腺素能的。在人类中，皮肤上的不同反射驱动相互作用，使得大的血管收缩反应（例如，例如，在一个实施例中，压力感受性反射）在高温或直接局部加热期间仍然被诱发。因此，在直立姿势、运动、出血等期间，尽管存在竞争性热驱动，但中心到外周体积位移最小化。静脉由交感肾上腺素能神经支配，交感肾上腺素能神经反射性地控制静脉的体积。
A major function of cutaneous blood flow is to regulate body temperature. Over most of its great range, skin blood flow far exceeds the metabolic needs of the skin. Cutaneous arterioles and veins are predominantly under neural control from a rich sympathetic adrenergic nerve supply, especially in acral regions. These tonically active, vasoconstrictor nerve fibers are the efferent arm of (1) thermoregulatory reflexes which originate principally in cutaneous thermoreceptors, (2) baroreflexes which originate in both arterial and cardiopulmonary baroreceptors, (3) chemoreceptor reflexes, and (4) reflex responses to upright posture and exercise. Cutaneous vasculature in man is probably unique in its great range and high responsiveness to these reflex drives. Human skin is also unique in possessing a neurogenic vasodilator system that is the principal efferent arm of reflexes which originate in the central thermoreceptors. Apparently, this system participates only in thermoregulatory reflexes; its transmitter is still unknown; and it controls skin blood flow over the full range and over most of the body. In man and baboons, the reflex modification in skin blood flow with each degree (C°) change in central temperature is about 20 times greater than that produced by changing skin temperature. However, in baboons and probably other species, the skin vasomotor system appears to be mainly adrenergic. In man, different reflex drives on skin interact so that the large vasoconstrictor responses (e. g., baroreflex) are still elicited during hyperthermia or direct local heating. Thus, central to peripheral volume displacement is minimized during upright posture, exercise, hemorrhage, etc. despite competing thermal drives. Veins are richly innervated by sympathetic adrenergic nerves which reflexly control their volume.