The role of nervous system Input Integration Output REGULATION Potential input Potential output ANTICIPATION Sensor Effector Cortex Cortex • •2 basic types: üNervous regulation üHumoral regulation üFeedback control - negative ü - positive ü • autoregulation – local regulation – system regulation Feedback regulation bal_simple_loop http://www.slideshare.net/drpsdeb/presentations •Main function: • • keep relatively constantaneous arterial blood pressure •Keep perfusion of tissues • •Tone of the vessels = basic tension of the smooth muscle inside of the wall • (vasoconstriction x vasodilatation) • •Regulation - local autoregulation • - system regulation •Autoregulation – the capacity of tissues to regulate their own blood flow •Myogenic theory – Bayliss phenomenon (as the pressure rises, the blood vessels are distended and the vascular smooth muscle fibres that surround the vessels contract; the wall tension is proportional to the distending pressure times the radius of the vessels – law of Laplace: • T=P x r) • •Metabolic theory – vasodilator substances tend to accumulate in active tissue, and these metabolites also contribute to autoregulation –ending products of energetic metabolism – CO2, lactate acid, K+ –effect of hypoxia (circulation: vasodilatation x pulmonary circulation: vasoconstriction) –Adenosin – coronary circulation: vasodilatation • •by substances which releasing from: – endothelium – tissues • •Substances secreted by the ENDOTHELIUM •Vasodilatation: •Nitric oxide (NO) from endothelial cells •(originally called: EDRF) • •Prostacyclin is produced by endothelial cells • •Vazoconstriction: • Endothelins (polypeptids – 21peptides) • three isopeptides: ET 1, ET 2 , ET 3 •Substances secreted by the tissues: •Histamine – primarily tissue hormones. •General affect: vasodilatation - decrease periphery resistence, blood pressure • •KININS: 2 related vasodilated peptides •Bradykinin + lysylbradykinin (kallidin). •Sweat glands, salivary glands •10x strongers than histamine •Relaxation of smooth muscle, decrease blood pressure • • •By hormones •Catecholamines – epinephrine, norepinephrine - effect as activation of sympathetic system •RAAS - stress situation •ADH - general vasoconstriction •Natriuretic hormones - vasodilatation •Autonomic nervous system •Sympathetic: vasoconstriction •All blood vessels except capillaries and venules contain smooth muscle and receive motor nerve fibers from sympathetic division of ANS (noradrenergic fibers) -Regulation of tissue blood flow -Regulation of blood pressure •Parasympathetic part: vasodilatation •Only sacral parasympathetic cholinergic fibres (Ach) inervated arteriols from external sex organs • http://www.studentconsult.com/common/showimage.cfm?mediaISBN=0721632564&FigFile=S23283-015-f004.jpg &size=fullsize Sympathetic nervous system Fight or flight response Energy/store consumption Preganglionic neuron – Spinal cord -Thoraco - lumbar system Ganglia Paravertebral -Truncus sympathicus - Majority Prevertebral -Plexus aorticus Mostly diffuse effect Parasympathetic nervous system Rest and digest response Energy conservation/en. store production Preganglionic neuron – Brain stem and spinal cord – cranio-sacral system Ganglia Close to target organs or intramurally Mostly local effect http://www.studentconsult.com/common/showimage.cfm?mediaISBN=0721632564&FigFile=S23283-015-f004.jpg &size=fullsize Sympatthetic nervous system Fight or flight response Energy/store consumption Preganglionic neuron – Spinal cord -Thoraco - lumbar system Ganglia Paravertebral -Truncus sympathicus - Majority Prevertebral -Plexus aorticus Mostly diffuse effect Parasympathetic nervous system Rest and digest response Energy conservation/energy store production Preganglionic neuron – Brain stem and spinal cord – cranio-sacral system Ganglia Close to target organs or intramurally Mostly local effect http://ccn.aacnjournals.org/content/27/1/30/T1.large.jpg Mediators of somatic and autonomic nervous system • C:\Users\w\Downloads\105365259.png https://www.google.cz/url?sa=i&rct=j&q=&esrc=s&source=imgres&cd=&ved=0ahUKEwjujdLGieLPAhVJOhQKHay0B nUQjBwIBA&url=http%3A%2F%2Fimg.docstoccdn.com%2Fthumb%2Forig%2F105365259.png&psig=AFQjCNFxrUy63llCA lny-Vhlyse4FHDMaw&ust=1476801796194278 Acetylcholine •Preganglionic fibers •Sympathetic •Parasympathetic üNicotinic receptor –Ligand-gated ion channels –Na+, K+, Ca2+ –Neuronal (NN) and muscle (NM) type –Excitatory •Postganglionic fibers •Parasympathetic üMuscarinic receptor –G-coupled –Excitatory •M1, M3, M5 –Inhibitory •M2, M4 Acetylcholine.svg http://www.mdpi.com/marinedrugs/marinedrugs-12-02970/article_deploy/html/images/marinedrugs-12-0297 0-g013-1024.png http://www.mdpi.com/marinedrugs/marinedrugs-12-02970/article_deploy/html/images/marinedrugs-12-0297 0-g013-1024.png https://s-media-cache-ak0.pinimg.com/originals/ea/6c/3e/ea6c3e44afe638dca65fb4a3014bc095.jpg https://s-media-cache-ak0.pinimg.com/originals/ea/6c/3e/ea6c3e44afe638dca65fb4a3014bc095.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Adrenoceptor-Signal_transduktion.PNG/400p x-Adrenoceptor-Signal_transduktion.PNG Norepinephrine •Dřeň nadledvin –Modifikované sympatické ganglion –„Transmitery“ (stresové hormony) vylučuje do krve •Noradrenalin •Adrenalin Norepinephrine.svg http://antranik.org/wp-content/uploads/2011/11/the-adrenal-medulla-of-the-adrenal-gland-epinephrine -norepinephrine-splanchic-nerves.jpg •Adrenal medulla –Modified sympathetic ganglion –„Transmitters“ (stress hormones) secreted into the blood stream •Norepinephrine •Epinephrine http://antranik.org/wp-content/uploads/2011/11/the-adrenal-medulla-of-the-adrenal-gland-epinephrine -norepinephrine-splanchic-nerves.jpg •Postganglionic sympathetic fibers •Adrenergic receptor –G-coupled –α type– generally excitatory (contraction) –b type – generally inhibitory (relaxation) with an exception of !!! heart !!! • https://upload.wikimedia.org/wikipedia/commons/thumb/f/f7/Adrenoceptor-Signal_transduktion.PNG/400p x-Adrenoceptor-Signal_transduktion.PNG Norepinephrine •Dřeň nadledvin –Modifikované sympatické ganglion –„Transmitery“ (stresové hormony) vylučuje do krve •Noradrenalin •Adrenalin Norepinephrine.svg http://antranik.org/wp-content/uploads/2011/11/the-adrenal-medulla-of-the-adrenal-gland-epinephrine -norepinephrine-splanchic-nerves.jpg •Adrenal medulla –Modified sympathetic ganglion –„Transmitters“ (stress hormones) secreted into the blood stream •Norepinephrine •Epinephrine http://antranik.org/wp-content/uploads/2011/11/the-adrenal-medulla-of-the-adrenal-gland-epinephrine -norepinephrine-splanchic-nerves.jpg •Postganglionic sympathetic fibers •Adrenergic receptor –G-coupled –α type– generally excitatory (contraction) –b type – generally inhibitory (relaxation) with an exception of !!! heart !!! • https://s3.amazonaws.com/classconnection/769/flashcards/5928769/png/screen_shot_2014-11-04_at_92935 _am-1497B7358A4552ACB39.png •http://2.bp.blogspot.com/_MJ0CEYnSB4U/S99IJTUruOI/AAAAAAAAACs/NPzsh8ydzjQ/s1600/redistributionofbl oodflow.jpg redistributionofbloodflow.jpg •http://2.bp.blogspot.com/_MJ0CEYnSB4U/S99IJTUruOI/AAAAAAAAACs/NPzsh8ydzjQ/s1600/redistributionofbl oodflow.jpg redistributionofbloodflow.jpg •The regulation of the heart: –Rami cardiaci n. vagi •Cardiac decelerator center - medula oblongata (ncl.dorsalis, ncl. ambiguus) – parasympathetic fibres of nervus vagus • : vagal tone (tonic vagal discharge) • •Negative chronotropic effect (on heart rate) •Negative inotropic effect (on contractility) •Negative dromotropic effect (on conductive tissue) • •The regulation of the heart: – nn. cardiaci •Cardiac accelerator center – spinal cord, sympathetic ganglia – sympathetic NS • •Positive chronotropic effect (on heart rate) •Positive inotropic effect (on contractility) •Positive dromotropic effect (on conductive tissue) • • •Vasomotor centre (regulation for function of vessels) •Medula oblongata ü presoric area (rostral and lateral part –vasoconstriction – increase blood pressure ü üdepresoric area (medio-caudalis part – vasodilatation, decrease of blood pressure) • • • •Influence by central nervous system – cerebral cortex – limbic cortex – hypothalamus Regulation of blood pressure Short - term regulation - baroreflex Middle - term regulation - humorals regulation • sympathetic - catecholamines • RAAS (decrease perfusion pressure in kidney – secretion of renin) • ADH Long – term regulation - kidney regulation Short term regulation BAROREFLEX Records of circulatory parameters obr11 Variability of circulatory parameters •Heart rate •Blood pressures – systolic and diastolic • • •variability expresses its fluctuation around the average value at certain time intervals (or in various conditions) Heart Rate Variability (HRV) •Informs us about the activity of the vagus nerve (tonic activity of n.vagus = vagal tone) •Time analysis: •from Holter monitoring ECG or 5 - 30min records ECG •It is basically a statistical evaluation +/-standard deviation •Disables intervals differing by more than 20% from the average, thus further processed only normal (NN) intervals and evaluated by the standard deviation of all NN sequence for 24h •Spectral analysis: •Carried out under standard conditions at various maneuvers (supine, standing); evaluated with 300 representative intervals RR / NN / •Another mathematical processing (Fourier transform) -length RR intervals are converted to cycles in Hz •The spectrum is divided into several components - low (LF: the sympathetic modulation) and high frequency (HF: vagal modulation) • People with reduced heart rate variability have a 5 times higher risk of death > > parasympathicus • CIRCULATORY FAILURE •The main function of circulation is keep a good organ and tissue perfusion • • BP = CO x TPR •Circulatory failure is a generalized inadequate blood flow in the body that causes tissue damage due to reduced blood flow - reduced transport of oxygen (and other nutritional factors). The cardiovascular system itself (cardiac muscle, vascular walls, vasomotor system, and other parts of circulation) worsens when coming „circulatory shock“ CIRCULATORY FAILURE • BP = CO x TPR •CO decrease: ülower volume in circulation – lower venous return •decrease of filling pressure and by Frank- Starling principle decrease of CO •Clinical: e.g. hemorrhagic shock, hypovolemic shock •Therapy: infusion (e.g. of physiological solution) CIRCULATORY FAILURE • BP = CO x TPR •CO decrease: üvasodilatation of venous system - sudden periphery vasodilatation – e.g. sudden loss of vasomotor tone : vasomotor syncope (neurogenic shock-brain damage, deep anesthesia) üemotional activation of parasympathetic signals to slow the heart and also activation of inverse sympathetic signals to dilate the peripheral vasculature : vasovagal syncope (emotional disturbance-fainting in young people) CIRCULATORY FAILURE • BP = CO x TPR •CO decrease: ülower pumping function of the heart •e.g. myocardial infarction, severe dysfunction of the heart valves, cardiac arrhythmias •Resultes: cardiogenic shock •= circulatory shock, which results from the weakened ability of the heart as a pump; (85% of people who develop a cardiogenic shock will not survive) CIRCULATORY FAILURE • BP = CO x TPR •TPR decrease: ütoxic vasodilatation (by histamin-allergy) – anaphylactic shock üDysbalance of autonomy nervous system – sympathetic part – decrease of sympathetic tone of vessels NYHA classification Clipboard07.bmp •SYNCOPA - a manifestation of brain ischemia that arises with a sudden drop in blood pressure due to failure in circulation - if the lying - consciousness returns quickly - within one minute •If the pressure drops for several hours, they are metabolic changes in the ischemic organs and developing „a shock“ •SHOCK = is acute circulatory insufficiency syndrome with manifestations of tissue ischemia in a different areas of the body