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Archives of Craniofacial Surgery Feb 2021Botulinum toxin type A (BoNT-A), onabotulinumtoxinA (Botox) was approved by the United States Food and Drug Administration for temporary improvement of glabellar lines...
Botulinum toxin type A (BoNT-A), onabotulinumtoxinA (Botox) was approved by the United States Food and Drug Administration for temporary improvement of glabellar lines in patients 65 years and younger in 2002, and has also been used widely for aesthetic purposes such as hyperhidrosis, body shape contouring, and other noninvasive facial procedures. BoNT-A inhibits presynaptic exocytosis of acetylcholine (ACh)-containing vesicles into the neuromuscular junction at cholinergic nerve endings of the peripheral nervous system, thereby paralyzing skeletal muscles. ACh is the most broadly used neurotransmitter in the somatic nervous system, preganglionic and postganglionic fibers of parasympathetic nerves, and preganglionic fibers or postganglionic sudomotor nerves of sympathetic nerves. The scientific basis for using BoNT-A in various cosmetic procedures is that its function goes beyond the dual role of muscle paralysis and neuromodulation by inhibiting the secretion of ACh. Although the major target organs for aesthetic procedures are facial expression muscles, skeletal body muscles, salivary glands, and sweat glands, which are innervated by the somatic or autonomic nerves of the peripheral cholinergic nerve system, few studies have attempted to directly explain the anatomy of the areas targeted for injection by addressing the neural physiology and rationale for specific aesthetic applications of BoNT-A therapy. In this article, we classify the various cosmetic uses of BoNT-A according to the relevant component of the peripheral nervous system, and describe scientific theories regarding the anatomy and physiology of the cholinergic nervous system. We also review critical physiological factors and conditions influencing the efficacy of BoNT-A for the rational aesthetic use of BoNT-A. We hope that this comprehensive review helps promote management policies to support long-term, safe, successful practice. Furthermore, based on this, we look forward to developing and expanding new advanced indications for the aesthetic use of BoNT-A in the future.
PubMed: 33714246
DOI: 10.7181/acfs.2021.00003 -
Clinical Autonomic Research : Official... Feb 2024We have re-evaluated the anatomical arguments that underlie the division of the spinal visceral outflow into sympathetic and parasympathetic divisions. (Review)
Review
PURPOSE
We have re-evaluated the anatomical arguments that underlie the division of the spinal visceral outflow into sympathetic and parasympathetic divisions.
METHODOLOGY
Using a systematic literature search, we mapped the location of catecholaminergic neurons throughout the mammalian peripheral nervous system. Subsequently, a narrative method was employed to characterize segment-dependent differences in the location of preganglionic cell bodies and the composition of white and gray rami communicantes.
RESULTS AND CONCLUSION
One hundred seventy studies were included in the systematic review, providing information on 389 anatomical structures. Catecholaminergic nerve fibers are present in most spinal and all cranial nerves and ganglia, including those that are known for their parasympathetic function. Along the entire spinal autonomic outflow pathways, proximal and distal catecholaminergic cell bodies are common in the head, thoracic, and abdominal and pelvic region, which invalidates the "short-versus-long preganglionic neuron" argument. Contrary to the classically confined outflow levels T1-L2 and S2-S4, preganglionic neurons have been found in the resulting lumbar gap. Preganglionic cell bodies that are located in the intermediolateral zone of the thoracolumbar spinal cord gradually nest more ventrally within the ventral motor nuclei at the lumbar and sacral levels, and their fibers bypass the white ramus communicans and sympathetic trunk to emerge directly from the spinal roots. Bypassing the sympathetic trunk, therefore, is not exclusive for the sacral outflow. We conclude that the autonomic outflow displays a conserved architecture along the entire spinal axis, and that the perceived differences in the anatomy of the autonomic thoracolumbar and sacral outflow are quantitative.
Topics: Animals; Humans; Neurons; Sympathetic Nervous System; Ganglia, Sympathetic; Spinal Cord; Sacrum; Mammals
PubMed: 38403748
DOI: 10.1007/s10286-024-01023-6 -
Scandinavian Journal of Pain Dec 2019Background and aims Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal - dominant hereditary neuropathy caused by a deficiency in the...
Background and aims Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal - dominant hereditary neuropathy caused by a deficiency in the peripheral protein PMP-22, due to deletion on chromosome 17p11,2 or in some rare cases point mutations in the PMP-22 gene. The clinical picture is characterized by recurrent mononeuropathies in nerves which frequently may be exposed to pressure, such as the median, ulnar, radial and peroneal nerves or also a more general neuropathy. Although pain is reported to be an unusual clinical symptom, there have been reports of pain in a surprisingly high proportion of these patients. Since pain may be explained by mechanisms in afferent small unmyelinated C- nerve fibers, an assessment of the function of small nerve fibers has been requested. The purpose of the present study was to investigate the presence of pain and the possible affection of afferent small nerve-fibers, A-δ and C-fibers, by quantitative sensory testing (QST)-assessment of thermal thresholds, as well as quantitative sudomotor axon reflex (QSART), a quantitative, validated assessment of efferent postganglionic sumodotor function. QST values were compared to values of age- and sex matched healthy subjects. Methods The 19 patients were investigated clinically, with an emphasis on pain characteristics, with nerve conduction studies (NCS) of major nerves in upper- and lower extremity, small fiber testing (QST, measurement of thermal thresholds) and with QSART. Results A total of 10 patients reported numbness in some extremity, suggesting entrapment of individual nerves as well as a general neuropathy, as verified by NCS in nine patients. A total of 15 patients had findings compatible with a general polyneuropathy. A total of eight patients reported pain, seven patients with pain in the feet, described as burning, aching, shooting and six with severe pathological QST values, mainly cold detection, but also four patients with elevated thresholds to warmth. Four of the patients had signs of a severe sensory neuropathy on NCS, with no sural findings. One patient had only pain in the arms, with only minor changes on NCS and with normal QST-values. Cold detection thresholds (CD) were significantly elevated (reduced sensibility) on the dorsum of the foot (mean of two feet), in patients [26.0 °C (19.7-28.0)] as compared with healthy subjects [28.6 °C (27.4-29.6) p = 0.000]. There were also significantly elevated warmth detection thresholds (WD) in feet in patients 39.5 °C (36.4-42.9) compared to healthy subjects [37.7 °C (36.1-39.4) p = 0.048]. However, there were no significant differences in QST values between patients with and without pain. Conclusions Of a total of 19 patients with verified HNPP, eight patients (42.1%) suffered from neuropathic pain, mainly in both feet. Implications Due to the high percentage of pain in HNPP, it is important not to disregard this diagnosis in a patient presenting with pain. Since there are no significant differences in QST values in patients with and without pain, routine QST studies in HNPP do not seem necessary.
Topics: Adult; Arthrogryposis; Female; Foot; Hereditary Sensory and Motor Neuropathy; Humans; Hypesthesia; Male; Myelin Proteins; Neural Conduction; Neuralgia; Neurons, Afferent; Pain
PubMed: 31536037
DOI: 10.1515/sjpain-2019-0090 -
Journal of Molecular and Cellular... Jun 2020After cardiac damage, excessive neurite outgrowth (sympathetic hyperinnervation) can occur, which is related to ventricular arrhythmias/sudden cardiac death. Post-damage...
RATIONALE
After cardiac damage, excessive neurite outgrowth (sympathetic hyperinnervation) can occur, which is related to ventricular arrhythmias/sudden cardiac death. Post-damage reactivation of epicardium causes epicardium-derived cells (EPDCs) to acquire a mesenchymal character, contributing to cardiac regeneration. Whether EPDCs also contribute to cardiac re/hyperinnervation, is unknown.
AIM
To investigate whether mesenchymal EPDCs influence cardiac sympathetic innervation.
METHODS AND RESULTS
Sympathetic ganglia were co-cultured with mesenchymal EPDCs and/or myocardium, and neurite outgrowth and sprouting density were assessed. Results showed a significant increase in neurite density and directional (i.e. towards myocardium) outgrowth when ganglia were co-cultured with a combination of EPDCs and myocardium, as compared to cultures with EPDCs or myocardium alone. In absence of myocardium, this outgrowth was not directional. Neurite differentiation of PC12 cells in conditioned medium confirmed these results via a paracrine effect, in accordance with expression of neurotrophic factors in myocardial explants co-cultured with EPDCs. Of interest, EPDCs increased the expression of nerve growth factor (NGF) in cultured, but not in fresh myocardium, possibly due to an "ischemic state" of cultured myocardium, supported by TUNEL and Hif1α expression. Cardiac tissues after myocardial infarction showed robust NGF expression in the infarcted, but not remote area.
CONCLUSION
Neurite outgrowth and density increases significantly in the presence of EPDCs by a paracrine effect, indicating a new role for EPDCs in the occurrence of sympathetic re/hyperinnervation after cardiac damage.
Topics: Animals; Apoptosis; Cell Line, Tumor; Cells, Cultured; Ganglia, Sympathetic; Heart; Humans; Mice; Myocardium; Nerve Growth Factor; Neuronal Outgrowth; Pericardium; Sympathetic Fibers, Postganglionic
PubMed: 32277975
DOI: 10.1016/j.yjmcc.2020.04.006 -
American Journal of Physiology.... Sep 2001With advances in experimental techniques, the early views of the sympathetic nervous system as a monolithic effector activated globally in situations requiring a rapid... (Review)
Review
With advances in experimental techniques, the early views of the sympathetic nervous system as a monolithic effector activated globally in situations requiring a rapid and aggressive response to life-threatening danger have been eclipsed by an organizational model featuring an extensive array of functionally specific output channels that can be simultaneously activated or inhibited in combinations that result in the patterns of autonomic activity supporting behavior and mediating homeostatic reflexes. With this perspective, the defense response is but one of the many activational states of the central autonomic network. This review summarizes evidence for the existence of tissue-specific sympathetic output pathways, which are likely to include distinct populations of premotor neurons whose target specificity could be assessed using the functional fingerprints developed from characterizations of postganglionic efferents to known targets. The differential responses in sympathetic outflows to stimulation of reflex inputs suggest that the circuits regulating the activity of sympathetic premotor neurons must have parallel access to groups of premotor neurons controlling different functions but that these connections vary in their ability to influence different sympathetic outputs. Understanding the structural and physiological substrates antecedent to premotor neurons that mediate the differential control of sympathetic outflows, including those to noncardiovascular targets, represents a challenge to our current technical and analytic approaches.
Topics: Adipose Tissue, Brown; Adrenal Medulla; Behavior; Ganglia, Sympathetic; Homeostasis; Nerve Net; Neural Pathways; Neurons; Organ Specificity; Periaqueductal Gray; Reflex; Sympathetic Fibers, Postganglionic; Sympathetic Nervous System; Vasomotor System
PubMed: 11506981
DOI: 10.1152/ajpregu.2001.281.3.R683 -
PloS One 2014Cardiac sympathetic neurodegeneration and dysautonomia affect patients with sporadic and familial Parkinson's disease (PD) and are currently proposed as prodromal signs...
Cardiac sympathetic neurodegeneration and dysautonomia affect patients with sporadic and familial Parkinson's disease (PD) and are currently proposed as prodromal signs of PD. We have recently developed a nonhuman primate model of cardiac dysautonomia by iv 6-hydroxydopamine (6-OHDA). Our in vivo findings included decreased cardiac uptake of a sympathetic radioligand and circulating catecholamines; here we report the postmortem characterization of the model. Ten adult rhesus monkeys (5-17 yrs old) were used in this study. Five animals received 6-OHDA (50 mg/kg i.v.) and five were age-matched controls. Three months post-neurotoxin the animals were euthanized; hearts and adrenal glands were processed for immunohistochemistry. Quantification of immunoreactivity (ir) of stainings was performed by an investigator blind to the treatment group using NIH ImageJ software (for cardiac bundles and adrenals, area above threshold and optical density) and MBF StereoInvestigator (for cardiac fibers, area fraction fractionator probe). Sympathetic cardiac nerve bundle analysis and fiber area density showed a significant reduction in global cardiac tyrosine hydroxylase-ir (TH; catecholaminergic marker) in 6-OHDA animals compared to controls. Quantification of protein gene protein 9.5 (pan-neuronal marker) positive cardiac fibers showed a significant deficit in 6-OHDA monkeys compared to controls and correlated with TH-ir fiber area. Semi-quantitative evaluation of human leukocyte antigen-ir (inflammatory marker) and nitrotyrosine-ir (oxidative stress marker) did not show significant changes 3 months post-neurotoxin. Cardiac nerve bundle α-synuclein-ir (presynaptic protein) was reduced (trend) in 6-OHDA treated monkeys; insoluble proteinase-K resistant α-synuclein (typical of PD pathology) was not observed. In the adrenal medulla, 6-OHDA monkeys had significantly reduced TH-ir and aminoacid decarboxylase-ir. Our results confirm that systemic 6-OHDA dosing to nonhuman primates induces cardiac sympathetic neurodegeneration and loss of catecholaminergic enzymes in the adrenal medulla, and suggests that this model can be used as a platform to evaluate disease-modifying strategies aiming to induce peripheral neuroprotection.
Topics: Adrenal Medulla; Animals; Aromatic-L-Amino-Acid Decarboxylases; Autonomic Fibers, Postganglionic; Chromaffin Cells; Disease Models, Animal; Female; Heart; Macaca mulatta; Male; Myocardium; Nerve Degeneration; Oxidopamine; Parkinson Disease, Secondary; Sympathectomy; Tyrosine 3-Monooxygenase; alpha-Synuclein
PubMed: 25133405
DOI: 10.1371/journal.pone.0104850 -
Autonomic Neuroscience : Basic &... Jul 2011The use of microneurography to measure muscle sympathetic nerve activity has provided important insights in human physiology. However, placing microelectrodes into... (Review)
Review
The use of microneurography to measure muscle sympathetic nerve activity has provided important insights in human physiology. However, placing microelectrodes into nerves can be challenging, particularly in certain patient populations. In this paper, we describe the use of real-time ultrasound guidance to assist with microneurography, including advantages, disadvantages, and proper training.
Topics: Autonomic Fibers, Postganglionic; Computer Systems; Humans; Microelectrodes; Peroneal Nerve; Radial Nerve; Sympathetic Nervous System; Ultrasonography
PubMed: 21514900
DOI: 10.1016/j.autneu.2011.03.007 -
Journal of Anatomy Jan 2021Cardiac reflexes originating from sensory receptors in the heart ensure blood supply to vital tissues and organs in the face of constantly changing demands. Atrial...
Cardiac reflexes originating from sensory receptors in the heart ensure blood supply to vital tissues and organs in the face of constantly changing demands. Atrial volume receptors are mechanically sensitive vagal afferents which relay to the medulla and hypothalamus, affecting vasopressin release and renal sympathetic activity. To date, two anatomically distinct sensory endings have been identified which may subserve cardiac mechanosensation: end-nets and flower-spray endings. To map the distribution of atrial receptors in the subendocardial space, we have double-labelled rat right atrial whole mounts for neurofilament heavy chain (NFH) and synaptic vesicle protein 2 (SV2) and generated high-resolution maps of the rat subendocardial neural plexus at the cavo-atrial region. In order to elucidate the nature of these fibres, double labelling with synaptophysin (SYN) and either NFH, calcitonin gene-related peptide (CGRP), choline acetyltransferase (ChAT) or tyrosine hydroxylase (TH) was performed. The findings show that subendocardial nerve nets are denser at the superior cavo-atrial junction than the mid-atrial region. Adluminal plexuses had the finest diameters and stained positively for synaptic vesicles (SV2 and SYN), CGRP and TH. These plexuses may represent sympathetic post-ganglionic fibres and/or sensory afferents. The latter are candidate substrates for type B volume receptors which are excited by stretch during atrial filling. Deeper nerve fibres appeared coarser and may be cholinergic (positive staining for ChAT). Flower-spray endings were never observed using immunohistochemistry but were delineated clearly with the intravital stain methylene blue. We suggest that differing nerve fibre structures form the basis by which atrial deformation and hence atrial filling is reflected to the brain.
Topics: Animals; Autonomic Nervous System; Calcitonin Gene-Related Peptide; Choline O-Acetyltransferase; Heart; Immunohistochemistry; Nerve Fibers; Rats; Sensory Receptor Cells; Synaptophysin; Tyrosine 3-Monooxygenase
PubMed: 32783212
DOI: 10.1111/joa.13284 -
Journal of Neurological Surgery. Part... Jun 2022The vidian nerve provides parasympathetic innervation to the nasal cavity and the lacrimal gland. Previous anatomic studies have primarily focused on preservation or...
The vidian nerve provides parasympathetic innervation to the nasal cavity and the lacrimal gland. Previous anatomic studies have primarily focused on preservation or severance of the vidian nerve proximal to the pterygopalatine ganglion (PPG). This study aimed to assess its neural fibers within the pterygopalatine fossa after synapsing at the PPG, and to explore potential clinical implications for endoscopic endonasal skull base surgery. An endonasal transpterygoid approach was performed on eight cadaveric specimens (16 sides). The PPG and maxillary nerve within the pterygopalatine fossa were divided. The vidian nerve was traced retrograde into the foramen lacerum, and postganglionic fibers distal to the PPG were dissected following the zygomatic nerve into the orbit. Potential communicating branches between the ophthalmic nerve (V1) and the PPG were also explored. All sides showed a plexus of neural communications between the PPG and the maxillary nerve. The zygomatic nerve exits the maxillary nerve close to the foramen rotundum, piercing the orbitalis muscle to enter the orbit in all sides. The zygomatic nerve was identified running beneath the inferior rectus muscle toward a lateral direction. In 7/16 sides (43.75%), a connecting branch between V and the pterygopalatine ganglion was observed. Neural communications between the PPG and the maxillary nerve were present in all specimens. A neural branch from V to the PPG potentially contributes additional postganglionic parasympathetic function to the lacrimal gland.
PubMed: 35832986
DOI: 10.1055/s-0040-1722714