Active skin perfusion and thermoregulatory response in the hand following nerve injury and repair in human upper extremities

Longitudinal Study of Functional Reinnervation of the Denervated Skin by Collateral Sprouting of Peptidergic Nociceptive Nerves Utilizing Laser Doppler Imaging

“…Scanning laser Doppler flowmetry is a reliable and useful technique for the measurement of cutaneous blood flow under physiological and pathophysiological conditions including thermoregulatory vascular responses in the intact and denervated skin in both man and animals (Hu et al, 2012;Deng et al, 2016). Laser Doppler flowmetry directly measures the cutaneous blood perfusion based on the detection of frequency ("Doppler") shift of low-power monochromatic laser light reflected from the moving erythrocytes, but not from the stationary tissue elements in the skin (Rajan et al, 2009;Daly and Leahy, 2013;Allen and Howell, 2014).…”

The role of C-afferents in mediating neurogenic vasodilatation in plantar skin after acute sciatic nerve injury in rats

“…In the present study, the refinement and reduction of research animals were enforced by using minimal numbers of rats for each experiment, involving experienced and proficient experimenters in rodent surgery, and employing blind approach in data collection. A limitation of the present study is that the vascular physiology of rats may be different to some extent from that in humans, as indicated in our previous studies [7,9]. However, as rodents are the most widely used models in studying neuro-vascular control mechanisms, the findings in the present study have implications in understanding the pathophysiological sequela of peripheral nerve injuries in humans and the development of novel assessment of nerve regeneration in experimental settings [44].…”

“…n.s. non-significant recovery after peripheral nerve repair [7], suggest a pivotal role of afferent C-fibers in the regulation of blood flow in the skin, especially the glabrous regions of the skin.…”

“…Vasomotor activities of dermal vasculature in response to local thermal challenges mainly involve neural control mechanisms, including both sympathetic and sensory nerve fibers [1,6]. In previous studies, we found that both baseline blood perfusion and local thermal challengesinduced perfusion change in the skin were altered after peripheral nerve injury [7][8][9]. In rats, transection injury to the sciatic nerve or tibial nerve promptly resulted in a substantial increase in blood perfusion by several fold in ipsilateral plantar skin [8,9], whereas chronically denervated plantar skin did not exhibit a significant difference in blood perfusion as compared to the contralateral normal side [9].…”