Nerve Regeneration In Rats Research Articles

Alpha-lipoic acid loaded in chitosan conduit enhances sciatic nerve regeneration in rat.

To investigate the effect of topical administration of alpha-lipoic acid into chitosan conduit on peripheral nerve regeneration using a rat sciatic nerve transection model. Forty five Wistar rats were divided into three experimental groups randomly. A 10-mm gap of sciatic nerve was bridged with a chitosan conduit following surgical preparation and anesthesia. In treatment group, the conduit was filled with 30 µl alpha-lipoic acid (10 mg/kg/bw).It was filled with 30 µl phosphate buffered saline solution in control group. In Sham group sciatic nerve was just exposed. The recovery of nerve function was faster in treatment group than in control, at 4 and 8 weeks after surgery (P-value<0.05). Conduction velocity was better in treatment group than in control group at 4 and 12 weeks (P-value<0.05). Recovery index was higher in treatment group than the control group, 8 weeks after surgery (P-value <0.05). Greater nerve fiber diameter, axon diameter, and myelin sheath thickness were observed in treatment group compared to control group at 8 and 12 weeks after surgery (P-value<0.05). The immunoreactivity of regenerated axons and myelin sheath in treatment group were far more similar to sham group. Alpha-lipoic acid when loaded in a chitosan conduit could improve transected sciatic nerve regeneration in rat.

Time-course effect of electrical stimulation on nerve regeneration of diabetic rats.

BackgroundElectrical stimulation (ES) has been shown to promote nerve regeneration in rats with experimental diabetes induced using streptozotocin (STZ). However, the time-course effect of ES on nerve regeneration of diabetic animals has not been reported in previous studies. The present study attempted to examine the effect of different timing of ES after peripheral nerve transection in diabetic rats.Methodology/FindingsFifty Sprague-Dawley rats were used in the study. They were classified into five groups. STZ-induced diabetes was created in groups A to D. Normal animals in group E were used as the non-diabetic controls. The sciatic nerve was transected and repaired using a silicone rubber conduit across a 10-mm gap in all groups. Groups A to C received ES for 15 minutes every other day for 2 weeks. Stimulation was initiated on day 1 following the nerve repair for group A, day 8 for group B, and day 15 for group C. The diabetic control group D and the normal control group E received no ES. At 30 days after surgery in group A, histological evaluations showed a higher success percentage of regeneration across the 10-mm nerve gap, and the electrophysiological results showed significantly larger mean values of evoked muscle action potential area and amplitude of the reinnervated gastrocnemius muscle compared with group D.Conclusions/SignificanceIt is concluded that an immediate onset of ES may improve the functional recovery of large nerve defect in diabetic animals.

Evaluation of small intestine submucosa and poly(caprolactone-co-lactide) conduits for peripheral nerve regeneration.

The present study employed nerve guidance conduits (NGCs) only, which were made of small intestine submucosa (SIS) and poly(caprolactone-co-lactide) (PCLA) to promote nerve regeneration in a peripheral nerve injury (PNI) model with nerve defects of 15 mm. The SIS- and PCLA-NGCs were easily prepared by rolling of a SIS sheet and a bioplotter using PCLA, respectively. The prepared SIS- and PCLA-NGCs fulfilled the general requirement for use as artificial peripheral NGCs such as easy fabrication, reproducibility for mass production, suturability, sterilizability, wettability, and proper mechanical properties to resist collapsing when applied to in vivo implantation. The SIS- and PCLA-NGCs appeared to be well integrated into the host sciatic nerve without causing dislocations and serious inflammation. All NGCs stably maintained their NGC shape for 8 weeks without collapsing, which matched well with the nerve regeneration rate. Staining of the NGCs in the longitudinal direction showed that the regenerated nerves grew successfully from the SIS- and PCLA-NGCs through the sciatic nerve-injured gap and connected from the proximal to distal direction along the NGC axis. SIS-NGCs exhibited a higher nerve regeneration rate than PCLA-NGCs. Collectively, our results indicate that SIS- and PCLA-NGCs induced nerve regeneration in a PNI model, a finding that has significant implications in the future with regard to the feasibility of clinical nerve regeneration with SIS- and PCLA-NGCs prepared through an easy fabrication method using promising biomaterials.

Erythropoietin promotes peripheral nerve regeneration in rats by upregulating expression of insulin-like growth factor-1.

IntroductionErythropoietin (EPO) has been shown to have beneficial effects on peripheral nerve damage, but its mechanism of action remains incompletely understood. In this study we hypothesized that EPO promotes peripheral nerve repair via neurotrophic factor upregulation.Material and methodsThirty adult male Wistar rats were employed to establish a sciatic nerve injury model. They were then randomly divided into two groups to be subjected to different treatment: 0.9% saline (group A) and 5000 U/kg EPO (group B). The walking behavior of rats was evaluated by footprint analysis, and the nerve regeneration was assessed by electron microscopy. The expression of insulin-like growth factor-1 (IGF-1) in the injured sciatic nerves was detected by immunohistochemical analysis.ResultsCompared to saline treatment, EPO treatment led to the growth of myelin sheath, the recovery of normal morphology of axons and Schwann cells, and higher density of myelinated nerve fibers. Erythropoietin treatment promoted the recovery of SFI in the injured sciatic nerves. In addition, EPO treatment led to increased IGF-1 expression in the injured sciatic nerves.ConclusionsErythropoietin may promote peripheral nerve repair in a rat model of sciatic nerve injury through the upregulation of IGF-1 expression. These findings reveal a novel mechanism underlying the neurotrophic effects of EPO.

The effect of cerebro-spinal fluid in collagen guide channel on sciatic nerve regeneration in rat

The aim of this study was to evaluate the effect of cerebrospinal fluid (CSF) in nerve regeneration across the collagen guide channel in comparison with autograft. Forty adult male rats (250-300 g) were randomized into (1) collagen channel+CSF, (2) collagen channel+normal saline (NS), (3) autograft, and (4) sham surgery groups. The left sciatic nerve was exposed and a 10 mm nerve segment was cut and removed. In the collagen groups, the proximal and distal cuts ends of sciatic nerve were telescoped into the nerve guides and CSF or NS injected into collagen conduit. In the autograft group, the 10 mm nerve segment was turned backwards and used an autologous nerve graft. All animals were evaluated by sciatic functional index (SFI) and electrophysiology, histology, and immunohistochemistry testing. The improvements in SFI since the beginning of the last evaluation in experimental groups were measured. On days 49 and 60 post-operation, the mean SFI of the collagen+CSF group was significantly greater than the autograft group (P < 0.05). On day 90, the mean nerve conduction velocity (NCV) of the collagen+CSF group was greater than autograft group (P < 0.05). The number of myelinated fibers in the collagen+CSF group was significantly greater than that of the collagen + NS group at day 90 (P < 0.05). CSF in collagen nerve guide channel effectively enhances nerve regeneration and promotes functional recovery in injured sciatic nerve of rats.

Clinical strategies to enhance nerve regeneration.

The slow rate of nerve regeneration after injury or reconstruction remains a clinical problem because it prohibits the timely reinnervation of distant target muscles before the irreversible degeneration of the neuromuscular junction and breakdown of muscle tissue. As such, high (proximal) nerve injuries result in the incomplete recovery of motor function and poor functional outcomes despite current and timely surgical management. Experimentally, several strategies have been shown to enhance nerve regeneration and improve functional recovery in animal models but translation to clinical practice has not been realized. Two potential treatments, tacrolimus (immunosuppressant) and electrical stimulation are commonly used for other reconstructive indications and as such, are both readily available clinically. There is some evidence, which will be reviewed in subsequent sections, that these approaches may also be useful in enhancing neuronal regeneration.

Controlled release of nerve growth factor and basic fibroblast growth factor combined with small-gap anastomosis enhances sciatic nerve regeneration

ObjectivesNerve regeneration after peripheral nerve injury is a slow process with a limited degree of functional recovery, resulting in a high disability rate. Thus, accelerating the rate of nerve regeneration and improving the degree of nerve repair is a clinical challenge. This study aimed to investigate the role of growth factor gel combined with small-gap nerve anastomosis in the regeneration of sciatic nerve injury in rats. This was achieved by injecting nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) gel into a silicon chamber that bridged the transection of the nerve.MethodsIn 27 randomly chosen Sprague Dawley rats, a sharp blade was used to transect the right hind leg sciatic nerve. The rats were divided into 3 groups: in groups A and B, silicon tubes containing NGF and bFGF gel or saline, respectively, were used to bridge the nerve proximal and distal ends (3-mm gap), and in group C, the nerve proximal and distal ends were directly sutured. Eight weeks after surgery, the sciat...

Chitosan Degradation Products Promote Nerve Regeneration by Stimulating Schwann Cell Proliferation via miR-27a/FOXO1 Axis.

Natural polysaccharides are biomaterials widely used for constructing scaffolds in tissue engineering. While natural polysaccharides have been shown to robustly promote tissue regeneration, the underlying molecular mechanism remains largely unknown. Here, we show that chitooligosaccharides (COS), the intermediate products of chitosan degradation, stimulate peripheral nerve regeneration in rats. Our experiment also shows that COS stimulate the proliferation of Schwann cells (SCs) during nerve regeneration. By analyzing the transcriptome and gene regulatory network, we identified the miR-27a/FOXO1 axis as the main signaling pathway for mediating the proliferative effects of COS on SCs. COS increase the expression level of miR-27a and cause a reduction of FOXO1, which subsequently accelerates the cell cycle and stimulates SC proliferation to stimulate nerve regeneration. These findings define a basic pathway for oligosaccharides-mediated cell proliferation and reveal a novel aspect of polysaccharide biomaterials in tissue engineering.

Sciatic nerve regeneration in rats subjected to ketogenic diet

Objectives: Ketogenic diet (KD) is a high-fat-content diet with insufficiency of carbohydrates that induces ketogenesis. Besides its anticonvulsant properties, many studies have shown its neuroprotective effect in central nervous system, but its influence on peripheral nervous system has not been studied yet. We examined the influence of KD on regeneration of peripheral nerves in adult rats.Methods: Fifty one rats were divided into three experimental (n = 15) and one control (n = 6) groups. Right sciatic nerve was crushed and animals were kept on standard (ST group) or ketogenic diet, the latter was introduced 3 weeks before (KDB group) or on the day of surgery (KDA group). Functional (CatWalk) tests were performed once a week, and morphometric (fiber density, axon diameter, and myelin thickness) analysis of the nerves was made after 6 weeks. Body weight and blood ketone bodies level were estimated at the beginning and the end of experiment.Results: Functional analysis showed no differences between groups. Morphometric evaluation showed most similarities to the healthy (uncrushed) nerves in KDB group. Nerves in ST group differed mostly from all other groups. Ketone bodies were elevated in both KD groups, while post-surgery animals’ body weight was lower as compared to ST group.Discussion: Regeneration of sciatic nerves was improved in KD – preconditioned rats. These results suggest a neuroprotective effect of KD on peripheral nerves.

Use of natural neural scaffolds consisting of engineered vascular endothelial growth factor immobilized on ordered collagen fibers filled in a collagen tube for peripheral nerve regeneration in rats.

The search for effective strategies for peripheral nerve regeneration has attracted much attention in recent years. In this study, ordered collagen fibers were used as intraluminal fibers after nerve injury in rats. Vascular endothelial growth factor (VEGF) plays an important role in nerve regeneration, but its very fast initial burst of activity within a short time has largely limited its clinical use. For the stable binding of VEGF to ordered collagen fibers, we fused a collagen-binding domain (CBD) to VEGF through recombinant DNA technology. Then, we filled the ordered collagen fibers-CBD-VEGF targeting delivery system in a collagen tube to construct natural neural scaffolds, which were then used to bridge transected nerve stumps in a rat sciatic nerve transection model. After transplantation, the natural neural scaffolds showed minimal foreign body reactions and good integration into the host tissue. Oriented collagen fibers in the collagen tube could guide regenerating axons in an oriented manner to the distal, degenerating nerve segment, maximizing the chance of target reinnervation. Functional and histological analyses indicated that the recovery of nerve function in the natural neural scaffolds-treated group was superior to the other grafted groups. The guiding of oriented axonal regeneration and effective delivery systems surmounting the otherwise rapid and short-lived diffusion of growth factors in body fluids are two important strategies in promoting peripheral nerve regeneration. The natural neural scaffolds described take advantage of these two aspects and may produce synergistic effects. These properties qualified the artificial nerve conduits as a putative candidate system for the fabrication of peripheral nerve reconstruction devices.

Experimental role of cervical sympathetic block during facial nerve injury and regeneration in rats

To explore the effects of cervical sympathetic block (CSB) on facial nerve regeneration in rats and seek the optimal timing of treatment. A total of 72 adult Sprague-Dawley rats were divided randomly into 4 groups of sham-operation (sham), model control (NS), CSB1 and CSB2 (n = 18 each). Except for sham group, the model of peripheral facial paralysis was established for three other groups. After treating facial nerves injury with CSB at different timepoints, the behavioral changes of rats were observed.Electroneurography (ENoG) of injured nerves was performed and the expressions of glial cell derived neurotrophic factor (GDNF) of facial nerve nucleus were detected at different stages. The facial whisker movement function scores in sham, NS, CSB1 and CSB2 groups were 3.87 ± 0.35, 0.50 ± 0.52, 1.07 ± 0.62 and 0.81 ± 0.42 (F = 2.934, P = 0.035) at Day 7, 3.85 ± 0.37, 0.91 ± 0.52, 1.57 ± 0.65 and 1.07 ± 0.62 (F = 2.537, P = 0.038) at Day 14 and 3.85 ± 0.37, 1.71 ± 0.47, 3.00 ± 0.68 and 2.36 ± 0.49 (F = 3.627, P = 0.024) at Day 28. At Day 7, LatSD and AmpSD were not detected in NS, CSB1 and CSB2 groups.However, at Day 14, the values of LatSD were (1.26 ± 0.19), (6.67 ± 0.36), (4.67 ± 0.36) and (6.17 ± 0.36) ms, showing a significant difference (F = 3.052, P = 0.024) and AmpSD (6.42 ± 1.93), (2.16 ± 1.87), (4.16 ± 1.80) and (3.66 ± 1.40) mv, also a significance (F = 3.634, P = 0.021). And at Day 28, LatSD were (1.31 ± 0.17), (3.17 ± 0.19), (1.93 ± 0.12) and (2.60 ± 0.22) ms (F = 2.729, P = 0.032) and AmpSD (6.82 ± 2.30), (4.72 ± 5.23), (6.22 ± 3.50) and (5.82 ± 4.10) mv (F = 3.827, P = 0.019). The expression quantities of GDNF in 4 groups produced significant differences at Day 7 (4.67 ± 0.81, 13.52 ± 0.58, 26.17 ± 1.01 and 14.86 ± 1.03, F = 3.637, P = 0.028), Day 14 (5.67 ± 0.57, 24.41 ± 2.86, 26.52 ± 1.36 and 25.48 ± 1.42, F = 2.946, P = 0.031) and Day 28 (5.37 ± 0.92, 26.64 ± 1.68, 27.38 ± 1.66 and 25.69 ± 1.99, F = 4.273, P = 0.012). During early stage of facial nerve injury, the treatment of CSB may increase the expression of GDNF of facial nerve nucleus at early stage and thus accelerate the recovery of facial nerve injury in rats.

Continuous calcitonin administration enhances nerve regeneration in rats

Continuous calcitonin administration enhances nerve regeneration in rats

A Catuama e o bilobalide na regeneração nervosa periférica de ratos submetidos à secção do nervo isquiático

A Catuama® é a associação de quatro extratos hidroalcoolicos obtidos de plantas brasileiras (Paullinia cupana, Trichilia catigua, Ptychopetalum olacoides e Zingiber officinale) com conhecida ação neuroprotetora, anti-inflamatória, antioxidante e antidepressiva. O bilobalide é um componente extraído das folhas do Ginkgo biloba, que tem comprovada ação neuroprotetora nos sistemas nervosos central e periférico. O presente estudo avaliou os efeitos da Catuama® e do bilobalide na regeneração nervosa periférica de ratos submetidos à secção do nervo isquiático. Foram utilizados 40 ratos com implante de tubo de silicone preenchido por colágeno líquido, deixando-se um intervalo entre os segmentos nervosos de 10mm. Os animais foram divididos em 4 grupos: o grupo controle (A); os grupos que receberam a Catuama® administrada por via oral nos primeiros 28 dias de pós-operatório, nas doses de 100 (B) e 400mg.kg-1 (C); e o grupo que recebeu o bilobalide na dose de 200µM (D), este, adicionado ao colágeno líquido utilizado no implante de silicone. Os animais foram avaliados na primeira, quinta e décima semanas de pós-operatório pelo teste de marcha. Na décima semana, foi realizada avaliação eletrofisiológica e análises quantitativa e qualitativa dos cortes histológicos de amostras do nervo isquiático e do músculo gastrocnêmio. Em todas as análises utilizadas observou-se excelente regeneração dos nervos, no entanto, não foi encontrada diferença significativa (P&gt;0,05) entre os grupos experimentais e controle.

Facial nerve regeneration using basic fibroblast growth factor-impregnated gelatin microspheres in a rat model.

Basic fibroblast growth factor (bFGF) plays a crucial role in the regeneration of peripheral nerve defects by affecting nerve cells, Schwann cells and fibroblasts, and by promoting axon outgrowth from the proximal nerve stump. However, the use of exogenous bFGF for in vivo regeneration of the peripheral nerves is limited by its short in vivo half-life. In this study, a drug delivery system for bFGF was developed that uses acidic gelatin hydrogel, which sustainably released bFGF in vivo over several weeks; its ability to promote peripheral nerve regeneration was also examined. In 8-week-old Lewis rats, 7-mm gaps were made in the buccal branch of the left facial nerve. Acidic gelatin hydrogel microspheres (10 µl) with or without bFGF (50 µg) were infused into a 10 mm silicone tube using a micropipette, and the silicone tube was then implanted into the gap. A 1-mm long nerve stump was inserted into each end of the tube. Histological examination at 7 weeks after implantation revealed (1) a significantly increased rate of nerve regeneration, (2) inducement of a number of regenerating nerve axons, and (3) a better degree of maturation of nerve axons in the bFGF microsphere group than that in the bFGF-free microsphere group. Copyright © 2014 John Wiley & Sons, Ltd.

Functional effect of local administration of glial derived neurotrophic factor combined with inside-out artery graft on sciatic nerve regeneration in rat

Effect of local glial derived neurotrophic factor (GDNF) on nerve regeneration was assessed. Eighty male Wistar rats were divided into four experimental groups (n = 20), randomly: In transected group left sciatic nerve was transected and stumps were fixed in adjacent muscle. In treatment group defect was bridged using an artery graft filled with 10 μL GDNF. In artery group graft was filled with phosphate-buffered saline. In normal control group sciatic nerve was exposed and manipulated. Each group was subdivided into four subgroups of five animals each and nerve fibers were studied in a 16-week period. Behavioral, functional, electrophysiological and gastrocnemius muscle mass findings and morphometric indices confirmed faster recovery of regenerated axons in IOAG/GDNF than in IOAG group (p < 0.05). Immunohistochemical reactions to S-100 in IOAG/GDNF were more positive than that in IOAG group. GDNF improved functional recovery and morphometric indices of sciatic nerve. It could be considered as an effective treatment for peripheral nerve repair in practice.

The mesenchymal stem cell–derived microvesicles enhance sciatic nerve regeneration in rat

The accomplishment for desired functional peripheral nerve regeneration is still challenging despite various materials and methods. The effects of local application of omental adipose mesenchymal stromal cell-derived microvesicles (MVs) on peripheral nerve regeneration were studied using a rat sciatic nerve transection model. A 10-mm gap of sciatic nerve was bridged with a chitosan conduit. The rats were divided into five experimental groups randomly as follows: cultured undifferentiated omental adipose-derived stromal cells, rest mesenchymal stem cell-derived MVs (c-MVs), anti-inflammatory mesenchymal stem cell-derived MVs (anti-MVs), proinflammatory mesenchymal stem cell-derived MVs (pro-MVs), and negative control (Chit). The functional assessment of nerve regeneration (walking track analyses), electrophysiologic measurements, muscle mass measurements, as well as histomorphometrical and immunohistochemical indices showed drastic improvement in nerve regeneration in c-MVs and anti-MVs animals compared with pro-MVs animals (p < 0.05). The anti-inflammatory stem cell-derived MVs can be used as an alternative for the improvement of rat sciatic nerve regeneration.

Effects of valproic Acid on axonal regeneration and recovery of motor function after peripheral nerve injury in the rat.

Valproic acid (VPA) is used to be an effective anti-epileptic drug and mood stabilizer. It has recently been demonstrated that VPA could promote neurite outgrowth, activate the extracellular signal regulated kinase pathway, and increases bcl-2 and growth cone-associated protein 43 levels in spinal cord. In the present research we demonstrate the effect of VPA on peripheral nerve regeneration and recovery of motor function following sciatic nerve transaction in rats. The rats in VPA group and control group were administered with valproic acid (300mg/kg) and sodium chloride respectively after operation. Each animal was observed sciatic nerve index (SFI) at 2-week intervals and studied electrophysiology at 4-week intervals for 12 weeks. Histological and morphometrical analyses were performed 12 weeks after operation. Using the digital image-analysis system, thickness of the myelin sheath was measured, and total numbers of regenerated axons were counted. There was a significant difference in SFI, electrophysiological index (motor-nerve conduct velocity), and morphometrical results (regenerated axon number and thickness of myelin sheath) in nerve regeneration between the VPA group and controls (P<0.05). The results demonstrated that VPA is able to enhance sciatic nerve regeneration in rats, suggesting the potential clinical application of VPA for the treatment of peripheral nerve injury in humans.

Rat Sciatic Nerve Reconstruction Across a 30 mm Defect Bridged by an Oriented Porous PHBV Tube With Schwann Cell as Artificial Nerve Graft

An oriented poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nerve conduit has been used to evaluate its efficiency based on the promotion of peripheral nerve regeneration in rats. The oriented porous micropatterned artificial nerve conduit was designed onto the micropatterned silicon wafers, and then their surfaces were modified with oxygen plasma to increase cell adhesion. The designed conduits were investigated by cell culture analyses with Schwann cells (SCs). The conduits were implanted into a 30 mm gap in sciatic nerves of rats. Four months after surgery, the regenerated nerves were monitored and evaluated by macroscopic assessments and histology and behavioral analyses. Results of cellular analyses showed suitable properties of designed conduit for nerve regeneration. The results demonstrated that in the polymeric graft with SCs, the rat sciatic nerve trunk had been reconstructed with restoration of nerve continuity and formatted nerve fibers with myelination. Histological results demonstrated the presence of Schwann and glial cells in regenerated nerves. Functional recovery such as walking, swimming, and recovery of nociceptive function was illustrated for all the grafts especially conduits with SCs. This study proves the feasibility of the artificial nerve graft filled with SCs for peripheral nerve regeneration by bridging a longer defect in an animal model.

Effects of vitamin B12 on the corneal nerve regeneration in rats

The study was designed to investigate the effects of a new ophthalmic solution containing 0.05% vitamin B12 0.05% on corneal nerve regeneration in rats after corneal injury. Eyes of anesthetized male Wistar rats were subjected to corneal injury by removing the corneal epithelium with corneal brush (Algerbrush). After the epithelial debridement, the right eye of each animal received the instillation of one drop of the ophthalmic solution containing vitamin B12 0.05% plus taurine 0.5% and sodium hyaluronate 0.5% four time per day for 10 or 30 days. Left eyes were used as control and treated with solution containing taurine 0.5% and sodium hyaluronate 0.5% alone following the same regimen. Fluorescein staining by slit-lamp and morphological analysis was used to determine corneal wound healing. Immunohistochemistry, immunoblot and confocal microscopy were used to examine corneal re-innervation. Slit-lamp and histological analyses showed that re-epithelization of the corneas was accelerated in rats treated with vitamin B12. A clear-cut difference between the two groups of rats was seen after 10 days of treatment, whereas a near-to-complete re-epithelization was observed in both groups at 30 days. Vitamin B12 treatment had also a remarkable effect on corneal re-innervation, as shown by substantial increased in the expression of neurofilament 160 and β-III tubulin at both 10 and 30 days. The presence of SV2A-positive nerve endings suggests the presence of synapse-like specialized structures in corneal epithelium of the eye treated with vitamin B12. Our findings suggest that vitamin B12 treatment represents a powerful strategy to accelerate not only re-epithelization but also corneal re-innervation after mechanical injury.

Rat whisker movement after facial nerve lesion: Evidence for autonomic contraction of skeletal muscle

Vibrissal whisking is often employed to track facial nerve regeneration in rats; however, we have observed similar degrees of whisking recovery after facial nerve transection with or without repair. We hypothesized that the source of non-facial nerve-mediated whisker movement after chronic denervation was from autonomic, cholinergic axons traveling within the infraorbital branch of the trigeminal nerve (ION). Rats underwent unilateral facial nerve transection with repair (N=7) or resection without repair (N=11). Post-operative whisking amplitude was measured weekly across 10weeks, and during intraoperative stimulation of the ION and facial nerves at ⩾18weeks. Whisking was also measured after subsequent ION transection (N=6) or pharmacologic blocking of the autonomic ganglia using hexamethonium (N=3), and after snout cooling intended to elicit a vasodilation reflex (N=3). Whisking recovered more quickly and with greater amplitude in rats that underwent facial nerve repair compared to resection (P<0.05), but individual rats overlapped in whisking amplitude across both groups. In the resected rats, non-facial-nerve-mediated whisking was elicited by electrical stimulation of the ION, temporarily diminished following hexamethonium injection, abolished by transection of the ION, and rapidly and significantly (P<0.05) increased by snout cooling. Moreover, fibrillation-related whisker movements decreased in all rats during the initial recovery period (indicative of reinnervation), but re-appeared in the resected rats after undergoing ION transection (indicative of motor denervation). Cholinergic, parasympathetic axons traveling within the ION innervate whisker pad vasculature, and immunohistochemistry for vasoactive intestinal peptide revealed these axons branching extensively over whisker pad muscles and contacting neuromuscular junctions after facial nerve resection. This study provides the first behavioral and anatomical evidence of spontaneous autonomic innervation of skeletal muscle after motor nerve lesion, which not only has implications for interpreting facial nerve reinnervation results, but also calls into question whether autonomic-mediated innervation of striated muscle occurs naturally in other forms of neuropathy.