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Platelet-based Detection of Nitric Oxide in Blood by Measuring VASP Phosphorylation
Published on: January 7, 2019
A role for nitric oxide in active thermoregulatory vasodilation
1Department of Physiology, University of Texas Health Science Center, San Antonio 78284-7756.
The American Journal of Physiology
|May 1, 1993
Summary
Nitric oxide (NO) plays a key role in the vasodilation of rabbit ears during whole body heating (WBH). Blocking NO formation reduced ear blood flow, while restoring it with L-arginine reversed the effect.
Area of Science:
- Physiology
- Cardiovascular Research
- Neuroscience
Background:
- Whole body heating (WBH) in rabbits increases ear blood flow velocity (EBF) via active neurogenic vasodilation.
- Previous studies indicated this vasodilation is abolished by local nerve block.
Purpose of the Study:
- To investigate the role of nitric oxide (NO) in rabbit ear neurogenic vasodilation during hyperthermia.
- To determine if NO mediates the increase in EBF during WBH.
Main Methods:
- Rabbits were instrumented to measure arterial pressure, heart rate, and EBF using Doppler ultrasound.
- WBH was induced, and N omega-nitro-L-arginine (L-NNA), an NO synthesis inhibitor, was administered to the ear via lingual artery catheter.
- Ear vascular conductance (EVC) changes were monitored before and after L-NNA administration and subsequent L-arginine infusion.
Main Results:
- During WBH, EVC significantly increased.
- Administration of L-NNA led to a significant decrease in EVC after a latency period.
- Subsequent infusion of L-arginine restored EVC, confirming the role of NO.
Conclusions:
- Nitric oxide (NO) is involved in the active vasodilation of the rabbit ear during hyperthermia.
- NO mediates the neurogenic vasodilation response to whole body heating in this model.
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