Acetylcholine (ACh) is an organic chemical that functions in the brain and body of many types of animals as a neurotransmitter. Its name is derived from its chemical structure: it is an ester of acetic acid and choline. Parts in the body that use or are affected by acetylcholine are referred to as cholinergic. Substances that increase or decrease the overall activity of the cholinergic system are called cholinergics and anticholinergics, respectively.
An acetylcholine receptor is an integral membrane protein that responds to the binding of acetylcholine, a neurotransmitter.
A muscle relaxant is a drug that affects skeletal muscle function and decreases the muscle tone. It may be used to alleviate symptoms such as muscle spasms, pain, and hyperreflexia. The term "muscle relaxant" is used to refer to two major therapeutic groups: neuromuscular blockers and spasmolytics. Neuromuscular blockers act by interfering with transmission at the neuromuscular end plate and have no central nervous system (CNS) activity. They are often used during surgical procedures and in intensive care and emergency medicine to cause temporary paralysis. Spasmolytics, also known as "centrally acting" muscle relaxant, are used to alleviate musculoskeletal pain and spasms and to reduce spasticity in a variety of neurological conditions. While both neuromuscular blockers and spasmolytics are often grouped together as muscle relaxant, the term is commonly used to refer to spasmolytics only.
Anticholinergics are substances that block the action of the neurotransmitter called acetylcholine (ACh) at synapses in the central and peripheral nervous system.
Antihypertensives are a class of drugs that are used to treat hypertension. Antihypertensive therapy seeks to prevent the complications of high blood pressure, such as stroke and myocardial infarction. Evidence suggests that reduction of the blood pressure by 5 mmHg can decrease the risk of stroke by 34% and of ischaemic heart disease by 21%, and can reduce the likelihood of dementia, heart failure, and mortality from cardiovascular disease. There are many classes of antihypertensives, which lower blood pressure by different means. Among the most important and most widely used medications are thiazide diuretics, calcium channel blockers, ACE inhibitors, angiotensin II receptor antagonists (ARBs), and beta blockers.
Metoprolol, sold under the brand name Lopressor, among others, is a selective β1 receptor blocker medication. It is used to treat high blood pressure, chest pain due to poor blood flow to the heart, and a number of conditions involving an abnormally fast heart rate. By working on the beta-1 receptor of the cardiac muscle cells, it yields both a chronotropic and inotropic effect. It is also used to prevent further heart problems after myocardial infarction and to prevent headaches in those with migraines.
Epibatidine is a chlorinated alkaloid that is secreted by the Ecuadoran frog Epipedobates anthonyi and poison dart frogs from the Ameerega genus. It was discovered by John W. Daly in 1974, but its structure was not fully elucidated until 1992. Whether epibatidine is the first observed example of a chlorinated alkaloid remains controversial, due to challenges in conclusively identifying the compound from the limited samples collected by Daly. By the time that high-resolution spectrometry was used in 1991, there remained less than one milligram of extract from Daly's samples, raising concerns about possible contamination. Samples from other batches of the same species of frog failed to yield epibatidine.
Alpha-1 blockers constitute a variety of drugs that block the effect of catecholamines on alpha-1-adrenergic receptors. They are mainly used to treat benign prostatic hyperplasia (BPH), hypertension and post-traumatic stress disorder. Alpha-1 adrenergic receptors are present in vascular smooth muscle, the central nervous system, and other tissues. When alpha blockers bind to these receptors in vascular smooth muscle, they cause vasodilation.
Trimetaphan camsilate (INN) or trimethaphan camsylate (USAN), trade name Arfonad, is a drug that counteracts cholinergic transmission at the ganglion type of nicotinic receptors of the autonomic ganglia and therefore blocks both the sympathetic nervous system and the parasympathetic nervous system. It acts as a non-depolarizing competitive antagonist at the nicotinic acetylcholine receptor, is short-acting, and is given intravenously.
Hexamethonium is a non-depolarising ganglionic blocker, a nicotinic (nAChR) receptor antagonist that acts in autonomic ganglia by binding mostly in or on the nAChR receptor, and not the acetylcholine binding site itself. It does not have any effect on the muscarinic acetylcholine receptors (mAChR) located on target organs of the parasympathetic nervous system but acts as antagonist at the nicotinic acetylcholine receptors located in sympathetic and parasympathetic ganglia (nAChR).
Labetalol is a medication used to treat high blood pressure and in long term management of angina. This includes essential hypertension, hypertensive emergencies, and hypertension of pregnancy. In essential hypertension it is generally less preferred than a number of other blood pressure medications. It can be given by mouth or by injection into a vein.
Mecamylamine is a non-selective, non-competitive antagonist of the nicotinic acetylcholine receptors (nAChRs) that was introduced in the 1950s as an antihypertensive drug. In the United States, it was voluntarily withdrawn from the market in 2009 but was brought to market in 2013 as Vecamyl and eventually was marketed by Turing Pharmaceuticals.
Decamethonium (Syncurine) is a depolarizing muscle relaxant or neuromuscular blocking agent, and is used in anesthesia to induce paralysis.
Nebivolol is a beta blocker used to treat high blood pressure and heart failure. As with other β-blockers, it is generally a less preferred treatment for high blood pressure. It may be used by itself or with other blood pressure medication. It is taken by mouth.
A ganglionic blocker is a type of medication that inhibits transmission between preganglionic and postganglionic neurons in the autonomic nervous system, often by acting as a nicotinic receptor antagonist. Nicotinic acetylcholine receptors are found on skeletal muscle, but also within the route of transmission for the parasympathetic and sympathetic nervous system. More specifically, nicotinic receptors are found within the ganglia of the autonomic nervous system, allowing outgoing signals to be transmitted from the presynaptic to the postsynaptic cells. Thus, for example, blocking nicotinic acetylcholine receptors blocks both sympathetic (excitatory) and parasympathetic (calming) stimulation of the heart. The nicotinic antagonist hexamethonium, for example, does this by blocking the transmission of outgoing signals across the autonomic ganglia at the postsynaptic nicotinic acetylcholine receptor.
Surugatoxin (SGTX) is a type of venom found in the mid-gut digestive gland of the Japanese ivory mollusk Babyloniajaponica, a carnivorous gastropod. It functions as a ganglionic blocker of nicotinic acetylcholine receptors (nAChRs). The structurally and functionally related neosurugatoxin, also derived from Babylonia japonica, is an even more potent nAChR antagonist than SGTX.
Alpha-blockers, also known as α-blockers or α-adrenoreceptor antagonists, are a class of pharmacological agents that act as antagonists on α-adrenergic receptors (α-adrenoceptors).
Cocaine intoxication refers to the subjective, desired and adverse effects of cocaine on the mind and behavior of users. Both self-induced and involuntary cocaine intoxication have medical and legal implications.
Autonomic drugs can either inhibit or enhance the functions of the parasympathetic and sympathetic nervous systems. This type of drug can be used to treat a wide range of diseases, such as glaucoma, asthma, urinary, gastrointestinal and cardiopulmonary disorders.
Cholinergic blocking drugs are a group of drugs that block the action of acetylcholine (ACh), a neurotransmitter, in synapses of the cholinergic nervous system. They block acetylcholine from binding to cholinergic receptors, namely the nicotinic and muscarinic receptors.
