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Discovery And Development Of Beta-blockers
Beta-blocker, β adrenergic receptor antagonists (also called beta-blockers or β-blockers) were initially developed in the 1960s, for the treatment of angina pectoris but are now also used for hypertension, congestive heart failure and certain arrhythmias. In the 1950s, Dichloroisoprenaline, dichloroisoproterenol (DCI) was discovered to be a β-antagonist that blocked the effects of sympathomimetic amines on bronchodilation, uterine relaxation and heart stimulation. Although DCI had no clinical utility, a change in the compound did provide a clinical candidate, pronethalol, which was introduced in 1962. Development History The β-blockers are an immensely important class of drugs due to their high prevalence of use. The discovery of β-blockers reaches back to more than 100 years ago, when early investigators came up with the idea that catecholamines were binding selectively to receptor-like structures and that this was the cause of their pharmacological actions. In 194 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dichloroisoprenaline
Dichloroisoprenaline (DCI), also known as dichloroisoproterenol, was the first beta blocker ever to be developed. It is non-selective for the β1-adrenergic and β2-adrenergic receptors. DCI has low potency and acts as a partial agonist/antagonist at these receptors. Although DCI was of no clinical value itself, further developments from DCI eventually led to the development of the clinical candidate pronethalol (withdrawn due to carcinogenicity) and subsequently propranolol (the first clinically successful beta blocker). Dichloroisoprenaline is a racemic mixture of enantiomer In chemistry, an enantiomer (Help:IPA/English, /ɪˈnænti.əmər, ɛ-, -oʊ-/ Help:Pronunciation respelling key, ''ih-NAN-tee-ə-mər''), also known as an optical isomer, antipode, or optical antipode, is one of a pair of molecular entities whi ...s. References Beta blockers Chloroarenes Phenylethanolamines {{alkanederivative-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
β-adrenergic
The adrenergic receptors or adrenoceptors are a class of G protein-coupled receptors that are targets of many catecholamines like norepinephrine (noradrenaline) and epinephrine (adrenaline) produced by the body, but also many medications like beta blockers, beta-2 (β2) agonists and alpha-2 (α2) agonists, which are used to treat high blood pressure and asthma, for example. Many cells have these receptors, and the binding of a catecholamine to the receptor will generally stimulate the sympathetic nervous system (SNS). The SNS is responsible for the fight-or-flight response, which is triggered by experiences such as exercise or fear-causing situations. This response dilates pupils, increases heart rate, mobilizes energy, and diverts blood flow from non-essential organs to skeletal muscle. These effects together tend to increase physical performance momentarily. History By the turn of the 19th century, it was agreed that the stimulation of sympathetic nerves could cause dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Coronary Circulation
Coronary circulation is the Circulatory system#Coronary vessels, circulation of blood in the arteries and veins that supply the cardiac muscle, heart muscle (myocardium). Coronary arteries supply oxygen saturation (medicine), oxygenated blood to the heart muscle. #Cardiac veins, Cardiac veins then drain away the blood after it has been deoxygenated. Because the rest of the body, and most especially the brain, needs a steady supply of oxygenated blood that is free of all but the slightest interruptions, the heart is required to function continuously. Therefore its circulation is of major importance not only to its own tissues but to the entire body and even the level of consciousness of the brain from moment to moment. Interruptions of coronary circulation quickly cause heart attacks (myocardial infarctions), in which the heart muscle is damaged by hypoxia (medical), oxygen starvation. Such interruptions are usually caused by coronary ischemia linked to coronary artery disease, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Side Effects
In medicine, a side effect is an effect of the use of a medicinal drug or other treatment, usually adverse but sometimes beneficial, that is unintended. Herbal and traditional medicines also have side effects. A drug or procedure usually used for a specific effect may be used specifically because of a beneficial side-effect; this is termed " off-label use" until such use is approved. For instance, X-rays have long been used as an imaging technique; the discovery of their oncolytic capability led to their use in radiotherapy for ablation of malignant tumours. Frequency of side effects The World Health Organization and other health organisations characterise the probability of experiencing side effects as: * Very common, ≥ 1⁄10 * Common (frequent), 1⁄10 to 1⁄100 * Uncommon (infrequent), 1⁄100 to 1⁄1000 * Rare, 1⁄1000 to 1⁄10000 * Very rare, < 1⁄10000 The |
Potency (pharmacology)
In pharmacology, potency or biological potency is a measure of a drug's biological activity expressed in terms of the dose required to produce a pharmacological effect of given intensity. A highly potent drug (e.g., fentanyl, clonazepam, risperidone, benperidol, bumetanide) evokes a given response at low concentrations, while a drug of lower potency (e.g. morphine, alprazolam, ziprasidone, haloperidol, furosemide) evokes the same response only at higher concentrations. Higher potency does not necessarily mean greater effectiveness nor more side effects nor less side effects. Types of potency The International Union of Basic and Clinical Pharmacology (IUPHAR) has stated that "potency is an imprecise term that should always be further defined", and lists of types of potency as follows: Miscellaneous Lysergic acid diethylamide (LSD) is one of the most potent psychoactive drug A psychoactive drug, psychopharmaceutical, mind-altering drug, consciousness-altering drug, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
