Physiological and anatomical features of the autonomic nervous system. The autonomic nervous system (autonomous) – part of the nervous system, which innervates vessels and internal organs, wasps have schestvlyaya coordinate their work and the regulating metabolic and trophic processes (thereby maintaining homeostasis). She undermining of dividing by the central and peripheric includes two divisions: Symposium and matic and parasympathetic. On the central autonomic nervous B with relating include clusters of nerve cells forming the core (tse n try), which are located in the brain and spinal cord. To perefirich e skom department include autonomic fibers vegetative nodes (ganglion) in e getativnye nerve endings.
The physiological peculiarity of the autonomic nervous system is the following: 1) it is part of the whole body response; 2) has a low speed of the nerve signal; 3) is not subject to arbitrary control by the brain; 4) has three kinds of influences on the operation of the p ganas: 5) trigger (triggers bodies work, which work as failed); 6) correcting (amplifies or attenuates the operation org and new); 7) adaptively-trophic (including metabolic system, n and Board to restore homeostasis).
Anatomical feature of the autonomic nervous system is that the neurons that control muscles of internal organs and des e Zami, lie outside the central part of the autonomic nervous si with the theme and form clusters – ganglia. Thus, there is a complementary and Tel’nykh link between the central structures of the autonomic nervous system and effector. Fiber portion extending from the central neuro of newly to ganglion called preganglionic fibers and the portion volo to on going from the ganglia to effector – postganglionic fiber. The e getativnaya reflex arc consists of three units: a receptor (chus t pheno- neurons are located in the organs, and their axons in the rear part of e th root enters the spinal cord); Associative (not intercalated minutes ron located in the lateral horn of the spinal cord, through pregangliona p Noe fiber transmits the signal to the autonomic ganglia); efferent (mot and Tel’nykh neuron disposes in autonomic ganglia, and through postgan g lionarnoe fiber transmits the excitation of the working body).
The sympathetic and parasympathetic divisions of the nervous system have a number of differences. The preganglionic fibers of the sympathetic region come out of the thoracic and lumbar spinal cord, the ganglia are located near the central division, and from them are long postganglionic fibers. In the transfer of information from preganglionic fibers ganglion acetylcholine involved, but the major neurotransmitter that vozdeys t exists on effectors is norepinephrine. Activation of the sympathetic division causes ergotoropnye effects: increased excitability and conductivity of organ systems are enhanced metabolic processes proish about dit shortness of breath and palpitation, t. e. the body adapts to intense activity, the body’s defenses are activated. Long preganglionic parasympathetic fibers otdelanachin and are in the trunk and sacral regions of the spinal cord and ganglia positioning and are near effectors. The neurotransmitter acetylcholine takes part in the transfer of information from the preganglionic neuron to the ganglion and from the postganglionic neuron to the working organ. Activation parasimpat and Cesky department creates conditions for rest and recuperation. Gain and vayutsya mp about fotropnye processes: increased synthesis of digestive enzymes and increases the secretion of digestive glands. There is a decrease in heart rate and constriction of the pupils.
Normally between the sympathetic and parasympathetic divisions with y exists a delicate balance shifts which are caused by dis t viem external stimuli and internal environment. The action of both departments on the same organs most often leads to the opposite effect to them , t. e. they work as antagonists. In some cases, there is a synergy in the work of both departments: during digestion occurs Zoom e of the protein composition of saliva (the action of the sympathetic division) and led and chenie amount thereof (the action of the parasympathetic division). Almost l Noah off the sympathetic division is not dangerous to zhiznede I telnosti body, but irregularities in the parasympathetic Dep e la can lead to serious consequences: impaired regulation of blood on the supply, regulation of body temperature, fatigue comes quickly, that is. e. People in this state badly adapts to changing ambient in kg Ambient.