Acetylcholine (ACh) is an organic compound 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.
Hyoscyamine is a naturally occurring tropane alkaloid and plant toxin. It is a secondary metabolite found in certain plants of the family Solanaceae, including henbane, mandrake, angel's trumpets, jimsonweed, the sorcerers' tree, and Atropa belladonna. It is the levorotary isomer of atropine and thus sometimes known as levo-atropine.
Muscarine, L-(+)-muscarine, or muscarin is a natural product found in certain mushrooms, particularly in Inocybe and Clitocybe species, such as the deadly C. dealbata. Mushrooms in the genera Entoloma and Mycena have also been found to contain levels of muscarine which can be dangerous if ingested. Muscarine has been found in harmless trace amounts in Boletus, Hygrocybe, Lactarius and Russula. Trace concentrations of muscarine are also found in Amanita muscaria, though the pharmacologically more relevant compound from this mushroom is the Z-drug-like alkaloid muscimol. A. muscaria fruitbodies contain a variable dose of muscarine, usually around 0.0003% fresh weight. This is very low and toxicity symptoms occur very rarely. Inocybe and Clitocybe contain muscarine concentrations up to 1.6%.
A parasympathomimetic drug, sometimes called a cholinomimetic drug or cholinergic receptor stimulating agent, is a substance that stimulates the parasympathetic nervous system (PSNS). These chemicals are also called cholinergic drugs because acetylcholine (ACh) is the neurotransmitter used by the PSNS. Chemicals in this family can act either directly by stimulating the nicotinic or muscarinic receptors, or indirectly by inhibiting cholinesterase, promoting acetylcholine release, or other mechanisms. Common uses of parasympathomimetics include glaucoma, Sjögren syndrome and underactive bladder.
Chlorfenvinphos is an organophosphorus compound that was widely used as an insecticide and an acaricide. The molecule itself can be described as an enol ester derived from dichloroacetophenone and diethylphosphonic acid. Chlorfenvinphos has been included in many products since its first use in 1963. However, because of its toxic effect as a cholinesterase inhibitor it has been banned in several countries, including the United States and the European Union. Its use in the United States was discontinued in 1991.
Phytochemistry is the study of phytochemicals, which are chemicals derived from plants. Phytochemists strive to describe the structures of the large number of secondary metabolites found in plants, the functions of these compounds in human and plant biology, and the biosynthesis of these compounds. Plants synthesize phytochemicals for many reasons, including to protect themselves against insect attacks and plant diseases. The compounds found in plants are of many kinds, but most can be grouped into four major biosynthetic classes: alkaloids, phenylpropanoids, polyketides, and terpenoids.
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 occurs naturally 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.
A cholinergic crisis is an over-stimulation at a neuromuscular junction due to an excess of acetylcholine (ACh), as a result of the inactivity of the AChE enzyme, which normally breaks down acetylcholine.
Arecoline is a nicotinic acid-based mild parasympathomimetic stimulant alkaloid found in the areca nut, the fruit of the areca palm. It is an odourless oily liquid. It can bring a sense of enhanced alertness and energy along with mild feelings of euphoria and relaxation.
Lupinine is a quinolizidine alkaloid present in the genus Lupinus of the flowering plant family Fabaceae. The scientific literature contains many reports on the isolation and synthesis of this compound as well as a vast number of studies on its biosynthesis from its natural precursor, lysine. Studies have shown that lupinine hydrochloride is a mildly toxic acetylcholinesterase inhibitor and that lupinine has an inhibitory effect on acetylcholine receptors. The characteristically bitter taste of lupin beans, which come from the seeds of Lupinus plants, is attributable to the quinolizidine alkaloids which they contain, rendering them unsuitable for human and animal consumption unless handled properly. However, because lupin beans have potential nutritional value due to their high protein content, efforts have been made to reduce their alkaloid content through the development of "sweet" varieties of Lupinus.
Anabasine is a pyridine and piperidine alkaloid found in the tree tobacco plant, as well as in tree tobacco's close relative the common tobacco plant. It is a structural isomer of, and chemically similar to, nicotine. Its principal (historical) industrial use is as an insecticide.
Methyllycaconitine (MLA) is a diterpenoid alkaloid found in many species of Delphinium (larkspurs). In common with many other diterpenoid alkaloids, it is toxic to animals, although the acute toxicity varies with species. Methyllycaconitine was identified one of the principal toxins in larkspurs responsible for livestock poisoning in the mountain rangelands of North America. Methyllycaconitine has been explored as a possible therapeutic agent for the treatment of spastic paralysis, and it has been shown to have insecticidal properties. It has become an important molecular probe for studying the pharmacology of the nicotinic acetylcholine receptor.
A muscarinic acetylcholine receptor antagonist, also simply known as a muscarinic antagonist or as an antimuscarinic agent, is a type of anticholinergic drug that blocks the activity of the muscarinic acetylcholine receptors (mAChRs). The muscarinic receptors are proteins involved in the transmission of signals through certain parts of the nervous system, and muscarinic receptor antagonists work to prevent this transmission from occurring. Notably, muscarinic antagonists reduce the activation of the parasympathetic nervous system. The normal function of the parasympathetic system is often summarised as "rest-and-digest", and includes slowing of the heart, an increased rate of digestion, narrowing of the airways, promotion of urination, and sexual arousal. Muscarinic antagonists counter this parasympathetic "rest-and-digest" response, and also work elsewhere in both the central and peripheral nervous systems.
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.
Toxiferine, also known as c-toxiferine I, is one of the most toxic plant alkaloids known. It is derived from several plant species, including Strychnos toxifera and Chondrodendron tomentosum. Historically, it has been used as an arrow poison by indigenous peoples in South America for its neuromuscular blocking properties, allowing them to paralyze animals during hunting, but also possibly kill due to paralysis of the respiratory muscles. Toxiferine functions as an acetylcholine receptor (AChR) antagonist. The paralysis caused by toxiferine can in turn be antagonized by neostigmine.
Lupinus albifrons, silver lupine, white-leaf bush lupine, or evergreen lupine, is a species of lupine (lupin). It is native to California and Oregon, where it grows along the coast and in dry and open meadows, prairies and forest clearings. It is a member of several plant communities, including coastal sage scrub, chaparral, northern coastal scrub, foothill woodland, and yellow pine forest.
Lupinus sericeus is a species of flowering plant in the legume family known by the common name silky lupine or Pursh's silky lupine. It is native to western North America from British Columbia to Arizona and east to Alberta and Colorado.
Quinolizidine alkaloids are natural products that have a quinolizidine structure; this includes the lupine alkaloids.
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.
Anagyris foetida, is a species of flowering plant in the family Fabaceae, forming a malodorous, Summer-deciduous shrub or small tree 2-4m in height with green twigs bearing grey-green trifoliate leaves clad beneath in silvery hairs. The red-tinged, yellow, Laburnum-like flowers are borne on the previous season's growth and are pollinated mainly by birds and bees - notably the buff-tailed bumblebee.The large spot of red pigmentation on the flowers is located on the exterior of the standard, the interior of which bears, in turn, many small, deep red spots.
