Heart and blood vessels

Cardiovascular Effects. Eesions in the heart and blood vessels have been reported in humans acutely intoxicated with methyl parathion (Wofatox) (Fazekas 1971) and are discussed in Section 3.2.2.2. However, many of these lesions may be secondary to the effects of methyl parathion on the conduction system of the heart, to other components ingested, or to therapeutic regimens that some of these patients received. 

Caffeine and other methylxanthines affect cardiovascular function by directly modifying contractility of the heart and blood vessels and, indirectly, by influencing neurotransmission in the CNS and peripheral nervous system. 

An example of this type of reflex is the baroreceptor reflex (see Figure 1.2). Baroreceptors located in some of the major systemic arteries are sensory receptors that monitor blood pressure. If blood pressure decreases, the number of sensory impulses sent from the baroreceptors to the cardiovascular control center in the brainstem also decreases. As a result of this change in baroreceptor stimulation and sensory input to the brainstem, ANS discharge to the heart and blood vessels is adjusted to increase heart rate and vascular resistance so that blood pressure increases to its normal value. 

The cardiovascular system includes the heart, which serves as a pump for the blood, and the blood vessels, which transport blood throughout the body. Under normal conditions, this system is a continuous, closed circuit, meaning that the blood is found only in the heart and blood vessels. 

Vasomotor center. Autonomic nervous activity to the cardiovascular system is regulated by the vasomotor center (see Figure 15.4). Located in the lower pons and the medulla of the brainstem, the vasomotor center is an integrating center for blood pressure regulation. It receives several sources of input, processes this information, and then adjusts sympathetic and parasympathetic discharge to the heart and blood vessels accordingly. 

Loss of plasma volume leads to a decrease in MAP. Baroreceptors located in the aortic and carotid sinuses detect this fall in MAP and elicit reflex responses that include an increase in the overall activity of the sympathetic nervous system. Sympathetic stimulation of the heart and blood vessels leads to an increase in cardiac output (CO) and increased total peripheral resistance (TPR). These adjustments, which increase MAP, are responsible for the short-term regulation of blood pressure. Although increases in CO and TPR are effective in temporary maintenance of MAP and blood flow to the vital organs, these activities cannot persist indefinitely. Ultimately, plasma volume must be returned to normal (see Table 19.1). 

Cardiovascular Having to do with the heart and blood vessels. [NIH]... 

Cardiovascular disease Any abnormal condition characterized by dysfunction of the heart and blood vessels. CVD includes atherosclerosis (especially coronary heart disease, which can lead to heart attacks), cerebrovascular disease (e.g., stroke), and hypertension (high blood pressure). [NIH]... 

Competitive blocker of a-adrenergic receptors in heart and blood vessels Inhibits the enzyme HMG-CoA reductase and reduces the biosynthesis of cholesterol Acts as an angiotensin II receptor antagonist Inhibits the synthesis of prostaglandins via the selective inhibition of the enzyme cyclooxygenase-2... 

Cardiovasciilar system - in vitro systems for potential to prolong QT interval, effects on heart and blood vessels, anaesthetised and conscious (reflexes intact) animals with effects on heart rate, blood pressure, ECG... 

Surgery of the heart and blood vessels Give an initial dose of not less than 150 units/kg to patients undergoing total body perfusion for open heart surgery. Often, 300 units/kg is used for procedures less than 60 minutes and 400 units/kg is used for procedures more than 60 minutes. 

Metivier E, Marchais SJ, Guerin AP, et al. Pathophysiology of anaemia focus on the heart and blood vessels. Nephrol Dial Transplant. 2000 15 Suppl 3 14—18. 

Prompt intensive treatment with corticosteroids may be lifesaving when an excessive inflammatory reaction has resulted in septic shock. A massive infusion of corticosteroids can restore cardiac output and reverse hypotension by sensitizing the response of adrenoceptors in the heart and blood vessels to the stimulating action of catecholamines. This protective role of steroids may be due to a direct effect on vascular smooth muscle. The combination of glucocorticoids and dopamine therapy preserves renal blood flow during shock. 

A. Smoking is probably the most common method for Western users. Dried Salvia leaf is readily available from commercial sources and can be smoked without further preparation in tobacco pipes, joints, or water-pipes or bongs. Salvia must be smoked hot (hotter than tobacco is) in order for salvinorin to be vaporized. The smoke is inhaled fast and hot, deeply into the lungs. Several hits in quick succession are usually required. The smoke is irritating and probably has the same sort of health risks as tobacco smoke - cancer, bronchitis, emphysema, and heart and blood vessel disease. When smoking it is a good idea to have a sitter present although many smokers do not take this advice. 

Like zinc, copper and its compounds have been used since ancient times, with copper dust, acetate, sulfate and carbonate reported in Egyptian and Hindu prescriptions, and also used by Hippocrates and Galen. Copper arsenite was used in 1892 for anemia and debility. Copper sulfate was recommended to strengthen man, to stimulate the heart and blood vessels, to increase deposition of fat and to treat anemia. The adult requirement is 1.25 mg Cud-1, about one third of which is absorbed. TPN should be supplemented with 0.5—1.5 mg d-1 (adults) and 20 gg (kg weight)-1 d-1 (children). 

Neurogenic (sympathetic) vasoconstriction occurs, with its well-known effects upon heart and blood vessels. 

Criteria Committee, New York Heart Association, Inc. 1973. Diseases of the Heart and Blood Vessels Nomenclature and Criteria for Diagnosis, 7th ed. Boston Little, Brown. 

Pryor, W.A. (1985) Free Radical Reactions in Autoxidation, Cancer, Heart and Blood Vessel Diseases and Aging. This Volume. 

Q2 The heart and blood vessels are innervated by sympathetic nerves. The fight or flight response of the sympathetic system is activated in stress, and epinephrine (adrenaline) is released into the blood. These responses increase the rate and force of the heart and constrict many blood vessels, both of which raise BP. In addition, continued sympathetic stimulation eventually causes structural changes in blood vessels, activation ofthe renin-angiotensin system and procoagulant effects. If stress is prolonged, these responses contribute to a sustained increase in BP. 

CVD is attributed to disorders of the heart and blood vessels, and it includes coronary heart disease (heart attacks), stroke, hypertension, peripheral artery disease, rheumatic heart disease, congenital heart disease, and heart failure. On a global perspective, 30% of all deaths are from CVD, which ranks it the number... 

Beta adrenergic receptor antagonists reduce cardiac output (caused by negative chronotropic and inotropic effects), decrease renin release from the kidneys, and cause smooth muscle relaxation. However, blockage may also decrease secretion of insulin from pancreatic P-cells, which limits its use in T2D. Calcium channel antagonists act on L-type voltage gated channels in the heart and blood vessels to reduce vascular resistance and arterial pressure. Diuretics are also widely used to decrease blood pressure, particularly in the elderly and hypertensive black populations. 

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