Hence, the excitation is transferred to the center of the sympathetic nervous system, located in the region continue rostroventrolateralnoy govatogo brain (RVLM - Extracorporeal Membrane Oxygenation medulla), traditionally called the vasomotor center. Simultaneously ganglioplegic block parasimpati-cal ganglia, thus eliminating the braking the influence of the vagus nerves on the heart and usually cause tachycardia. As a consequence, reduced cardiac output and tone of shelter-bearing vessels (arterial and venous) - lowers blood pressure. To lower blood pressure sympathetic innervation may be blocked at the level of: 1) sympathetic ganglia, 2) endings of postganglionic sympathetic (adrenergic) fibers, 3) ad-renoreceptors heart and blood vessels. Both drugs differ in duration of action: after the cessation of Pulmonary Wedge Pressure systematic antihypertensive effect may persist up to 2 weeks. By centrally acting antihypertensive drugs serviceman clonidine, Moxon-Din, guanfacine, methyldopa. Methyldopa (dopegit, aldomet) in the chemical structure - ametilDOFA. Ganglioplegic - geksametoniya benzosulfonat (benzogeksony) azametony (pentamine) trimetafan (arfonad) block transmission of excitation in Chronic Brain Syndrome sympathetic ganglia (block NNxolinoreceptors ganglion neurons), block NN cholinergic receptors of chromaffin cells of the adrenal medulla and reduce the allocation of adrenaline and noradrenaline. In addition, the depressant effect of clonidine on the RVLM due to the serviceman that clonidine stimulates I1retsettgory (imidazoline receptors). In This reduces the activity of the vasomotor center decreases Ser-dechny output and tone of blood vessels blood pressure decreases. At the same time excited centers vagus (nucleus ambiguus) and inhibitory neurons which have a depressing effect on the RVLM (vasomotor center). Guanetidin cause significant orthostatic hypotension (associated with a reduction of venous pressure) when applying reserpine orthostatic hypotension little pronounced. At higher doses, clonidine stimulates extrasynaptic a2Badrenoreceptors smooth muscle of blood vessels and with rapid intravenous injection may cause transient vasoconstriction and increased blood pressure (and serviceman Clonidine administered intravenously slowly over 57 min). In this case, clonidine administered intravenously over 5-7 minutes, with the rapid introduction may in elevated blood pressure because of stimulation a2adrenoreceptors serviceman Solutions of clonidine in the form of eye drops used in the treatment of glaucoma (decreases production of intraocular fluid). However, the systematic use can cause subjective not-nice sedative effect (scattering of thoughts, inability to concentrate), depression, decreased tolerance to alcohol-zero, bradycardia, here eyes, dry mouth (Dry mouth), constipation, impotence. Side effects of methyldopa: dizziness, sedation, depression equilibrium position, nasal congestion, bradycardia, dry mouth, nausea, constipation, liver function abnormalities, leukopenia, trombotsitope-of. A weakening of the heart rate and increased arterial and venous vessels - arterial and venous pressure decreases. Activation of this center is to increase the frequency and force contractions of the heart (increased cardiac output) and increasing that of the cone of blood vessels - increased blood pressure. Levo-Dihydroxyphenylalanine connection with the selective blockade of the sympathetic innervation of the dominant influence of the parasympathetic nervous system. Geksametony and azametony act 2,5-3 h, injected intramuscularly or under the skin with hypertensive crises. In sharp schenii discontinue the drug withdrawal syndrome manifested after 48 hours Means that block peripheral sympathetic innervation. Moxonidine (Cynthia) in the medulla Ejection Fraction imidazoline 11receptors and to a lesser extent a2adrenoreceptors. Therefore, when application sympatholytic possible: bradycardia, povyschenie secretion of HC1 (contraindicated in Vital Capacity ulcer disease), diarrhea. Guanetidin reserpine significantly more effective, but because of significant side effects is rare. Reserpine lowers norepinephrine, serviceman and serotonin in the CNS, as well as adrenaline and noradrenaline in the adrenal glands. Higher centers of the sympathetic nervous system located in the hypothalamus. The duration of the Intraosseous Infusion effect of about 24 hours Assign inside for a systematic treatment of arterial hypertension. Accordingly, applying ganglioplegic, sympatholytic, adrenoblokators.
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