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

Abstract

Background: Vasomotor regulation of dermal blood vessels, which are critical in the function of the skin in thermoregulatory control, involves both neural and non-neural mechanisms. Whereas the role of sympathetic nerves in regulating vasomotor activities is comprehensively studied and well recognized, that of sensory nerves is underappreciated. Studies in rodents have shown that severance of the sciatic nerve leads to vasodilatation in the foot, but whether sympathetic or sensory nerve fibers or both are responsible for the neurogenic vasodilatation remains unknown. Results: In adult Sprague-Dawley rats, vasodilatation after transection of the sciatic nerve gradually diminished to normal within 3-4 days. The neurotmesis-induced neurogenic vasodilatation was not detectable when the sciatic nerve was chronically deafferentated by selective resection of the dorsal root ganglia (DRGs) that supply the nerve. Specific activation of C-afferents by intra-neural injection of capsaicin resulted in neurogenic vasodilatation to a magnitude comparable to that by neurotmesis, and transection of the sciatic nerve pre-injected with capsaicin did not induce further vasodilatation. Conclusions: Our results collectively indicate that vasodilatation after traumatic nerve injury in rats is predominantly mediated by C-fiber afferents.

Chronic alcohol induced mechanical allodynia by promoting neuroinflammation: A mouse model of alcohol‐evoked neuropathic pain

“…In line with this evidence, our data showing a reduction of the protein expression of S100, a marker of Schwann cells, in sciatic nerve tissue in 2BC-N mice compared with 2BC mice indicates neuropathy that developed in these animals. Small-fiber axons are enclosed within invaginations of the Schwann-cell membranes and C-fibers represents an important marker of neuropathy development (Chen et al, 2007;T. Zhang et al, 2020).…”

“…In line with this evidence, our data showing a reduction of the protein expression of S100, a marker of Schwann cells, in sciatic nerve tissue in 2BC‐N mice compared with 2BC mice indicates neuropathy that developed in these animals. Small‐fibre axons are enclosed within invaginations of the Schwann‐cell membranes and C‐fibres represents an important marker of neuropathy development (Chen & Levine, 2007; Zhang, Niu, et al, 2020). The decreased S100 protein expression observed in our work, support a lack of proper communication between the peripheral tissues and the CNS results in altered perception of the mechanical stimulus.…”

Neuronal nitric oxide synthase and calbindin expression in sympathetic preganglionic neurons following capsaicin treatment

“…Capsaicin treatment has been applied to study nociceptive action in the somatic and visceral afferent nervous systems. Stimulation of visceral afferent nerve fibers induces acute and chronic changes in sympathetic nerve activity (Ong et al, 2019; Shanks et al, 2018; Zhang et al, 2020). In our previous experiments, capsaicin treatment affected the morphology of sympathetic ganglionic neurons and led to a significant reduction in the number of neurofilament‐200‐immunoreactive (IR) neurons in the sympathetic ganglia (Porseva et al, 2013).…”

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

“…The correct author name is: Jiahui Niu. The author group has been updated above and the original article [1] has been corrected.…”