ENOS and nNOS contribution to reflex cutaneous vasodilation during dynamic exercise in humans
dc.contributor.author | McNamara, Tanner | |
dc.date.accessioned | 2012-05-03T17:52:49Z | |
dc.date.available | 2012-05-03T17:52:49Z | |
dc.date.graduationmonth | May | en_US |
dc.date.issued | 2012-05-03 | |
dc.date.published | 2012 | en_US |
dc.description.abstract | Recent data suggests nNOS mediates the NO-component of reflex cutaneous vasodilation with passive heat stress. Our hypothesis was nNOS, but not eNOS, inhibition would attenuate reflex cutaneous vasodilation during dynamic exercise. Protocol 1: subjects performed a VO[subscript]2 peak test on a supine cycle ergometer. Protocol 2: with experimental arm at heart level subjects cycled in supine posture at 60% VO[subscript]2 peak to raise core temperature (Tc) 0.8-1.0°C (35-45 min). In protocol 2 subjects were equipped with 4 microdialysis fibers on the forearm and each randomly assigned as: 1) lactated Ringer’s (control); 2) 5mM NPLA (nNOS inhibition); 3) 10mM L-NIO (eNOS inhibition); and 4) 20mM L-NAME (non- selective NOS inhibition). At the end of protocol 2 all sites were locally heated to 43°C and infused with SNP to elicit maximal dilation. Mean arterial pressure (MAP), skin blood flow via laser- Doppler flowmetry (LDF), and Tc via ingestible telemetric pill were measured; cutaneous vascular conductance (CVC) was calculated as LDF/MAP and normalized to maximum. In protocol 2 there was no significant difference between control (62±5 %CVCmax) and NPLA (61±6 %CVCmax). L-NIO (38±4 %CVCmax) and L-NAME (41±7 %CVCmax) significantly attenuated CVC compared to control and NPLA (p<0.001 all conditions). There was no difference between L-NIO and L- NAME. We conclude eNOS, not nNOS, contributes to reflex cutaneous vasodilation during dynamic exercise. | en_US |
dc.description.advisor | B.J. Wong | en_US |
dc.description.degree | Master of Science | en_US |
dc.description.department | Department of Kinesiology | en_US |
dc.description.level | Masters | en_US |
dc.identifier.uri | http://hdl.handle.net/2097/13788 | |
dc.language.iso | en_US | en_US |
dc.publisher | Kansas State University | en |
dc.subject | Cutaneous | en_US |
dc.subject | Vasodilation | en_US |
dc.subject | Skin | en_US |
dc.subject | Endothelial nitric oxide | en_US |
dc.subject | Neuronal nitric oxide | en_US |
dc.subject | Exercise | en_US |
dc.subject.umi | Kinesiology (0575) | en_US |
dc.title | ENOS and nNOS contribution to reflex cutaneous vasodilation during dynamic exercise in humans | en_US |
dc.type | Thesis | en_US |