OBJECTIVE: The aim of this study was to gain a better understanding of the hemodynamic actions of insulin on cutaneous microcirculation in persons with spinal cord injury (SCI). DESIGN: A prospective, open-label, nonrandomized, placebo-controlled investigation was performed in an otherwise healthy cohort of persons with SCI (n = 10) and in an age- and sex-matched cohort of control subjects whose neurologic function is intact (n = 10). Laser Doppler flowmetry characterized the peak blood perfusion unit (BPU) response (percent change from baseline) to insulin or placebo iontophoresis above and below the neurologic level of injury. RESULTS: Placebo iontophoresis did not result in any statistically significant changes in BPU. In the arm, insulin iontophoresis resulted in a 20% mean increase in BPU (P < 0.05) in the control group and a 9% mean increase in the SCI group (P = 0.14). In the leg, insulin iontophoresis resulted in an 81% (P < 0.01) mean increase in BPU in the control group and a 29% (P < 0.001) mean increase in BPU in the SCI group. The relative effect of insulin on the lower extremity BPU response was significantly greater (P < 0.05) in the control group compared with the SCI group (77% vs. 35%, respectively). CONCLUSIONS: The hemodynamic actions of insulin are markedly blunted in the sublesional microvasculature of persons with SCI, most likely as a result of impaired sublesional sympathetic nervous system control.
|Number of pages||9|
|Journal||American Journal of Physical Medicine and Rehabilitation|
|State||Published - Feb 2013|
- Laser Doppler Flowmetry
- Skin Blood Flow