The Role of Sympathetic Nervous System in Temperature Regulation
Hooshang Hooshmand in Chronic Pain, 2018
The anatomy of the sympathetic system is quite primitive. The system is intermingled with almost amoebic–shaped paraspinal ganglia and plexi. When an extremity becomes inactive, the sympathetic nervous system reflexly reduces blood circulation to the skin of the extremity. The central temperature regulation is achieved by the hypothalamus through the sympathetic nervous system both centrally and peripherally. The sympathetic nervous system functions symmetrically, and the increase and decrease of temperature in normal conditions is influenced by the sympathetic nervous system bilaterally. The sympathetic nervous system works quite symmetrically on the two sides of the body, and any significant thermal asymmetry on the surface of the skin points to dysfunction of this system. Normally the sympathetic nervous system quite consistently preserves this symmetry of temperature. The sympathetic nervous system stimulation enhances skin vasoconstriction on the one hand and bone and muscle vasodilation on the other. Inhibition of this system has the opposite effect.
Sympathetic Nervous System and Motor Function
Hooshang Hooshmand in Chronic Pain, 2018
Recognition of the influence of the sympathetic nervous system on muscle function is quite essential in successful management of reflex sympathetic dystrophy (RSD). Sympathetic block relieves muscle contraction and improves motor function of the extremity involved in RSD. The unpleasant nociceptive impulse results in hypertonicity, flexor muscles stimulation, spasticity, withdrawal, tremor, dystonia, and cold skin. The proprioceptive system exerts an inhibitory effect on the anterior horn cells and anterolateral horn cells. Surgery in the case of temporomandibular joint disease or thoracic outlet syndrome results in vicious circle and aggravation of RSD. The use of sympathetic block, heat, biofeedback, and transcutaneous nerve stimulator on trigger points relieves the pain and movement disorder. The selective therapeutic efficacy of sympathetic proximal nerve block in relief of hyperpathic pain as opposed to nonhyperpathic pain reflects the importance of efferent pathways in the development of RSD and hyperpathia.
Miscellaneous
Bobby Krishnachetty, Abdul Syed, Harriet Scott in Applied Anatomy for the FRCA, 2020
This chapter is intended to cover the anatomical knowledge of nerves that helps trainee anesthetists who are revising for the Primary and Final FRCA exams. The topics of importance to anesthetists are presented under 'structures', 'circulation' and 'nervous system'. The chapter includes a wide range of questions of clinical relevance that are asked in the exam. Peripheral nerves are formed of axons of neurons with cell bodies that reside in the central nervous system. The autonomic nervous system is the unconscious nervous system that deals with a series of involuntary functions controlling a number of actions within organs in the body. The sympathetic nervous system consists of a chain of fused ganglia that lie adjacent to the spinal cord bilaterally. The parasympathetic nervous system consists of preganglionic fibers originating from the brain stem of the motor nuclei of cranial nerves III, VII, IX and X and from the ventral rami of sacral nerves two, three and four (cranio-sacral outflow).
Origin of neuroblastic tumors: clues for future therapeutics
Published in Expert Review of Molecular Diagnostics, 2004
Neuroblastic tumors are the most common extracranial tumors of childhood. They arise from embryonal cells committed to the development of the sympathetic nervous system. In vivo and in vitro observations have shown that neuroblastic tumors appear to recapitulate the development of differentiating sympathetic neurons and chromaffin (neuroendocrine) cells of the sympathetic nervous system. This suggests that the origin of neuroblastic tumors resides as a block in the process of differentiation. This article summarizes the experimental data accumulated over the last three decades, which has provided some clues to the cellular origin of such tumors. In order to identify the cellular origin of these tumors, the embryology of the sympathetic nervous system is first reviewed and any archeological rests of normal development in the tumors are then discussed.
Stress, the Sympathetic Nervous System and Hypertension
Published in Journal of Human Stress, 1978
Stress may be an important contributor to the pathogenesis of idiopathic (essential) hypertension. The probable pathway involves activation of the sympathetic nervous system and thereby an increase in peripheral resistance. This paper reviews the hemodynamics of early hypertension and attempts to relate them to stress-mediated overactivity of the sympathetic nervous system. Attention is also given the relations between obesity, race, sex and geography to hypertension.
Clinical utility of sympathetic blockade in cardiovascular disease management
Published in Expert Review of Cardiovascular Therapy, 2017
ABSTRACT Introduction: A dysregulated sympathetic nervous system is a major factor in the development and progression of cardiovascular disease; thus, understanding the mechanism and function of the sympathetic nervous system and appropriately regulating sympathetic activity to treat various cardiovascular diseases are crucial. Areas covered: This review focused on previous studies in managing hypertension, atrial fibrillation, coronary artery disease, heart failure, and perioperative management with sympathetic blockade. We reviewed both pharmacological and non-pharmacological management. Expert commentary: Chronic sympathetic nervous system activation is related to several cardiovascular diseases mediated by various pathways. Advancement in measuring sympathetic activity makes visualizing noninvasively and evaluating the activation level even in single fibers possible. Evidence suggests that sympathetic blockade still has a role in managing hypertension and controlling the heart rate in atrial fibrillation. For ischemic heart disease, beta-adrenergic receptor antagonists have been considered a milestone drug to control symptoms and prevent long-term adverse effects, although its clinical implication has become less potent in the era of successful revascularization. Owing to pathologic involvement of sympathetic nervous system activation in heart failure progression, sympathetic blockade has proved its value in improving the clinical course of patients with heart failure.