Npc209773

DescriptionAtropine is a naturally occurring tropane alkaloid extracted from plants of the family Solanaceae including deadly nightshade (A. belladonna). It is a non-selective, competitive antagonist of the muscarinic acetylcholine receptor types M1, M2, M3, M4, and M5 (pKBs range from 8.9-9.8). Atropine increases firing of the sinoatrial node and conduction through the atrioventricular node of the heart, opposes the actions of the vagus nerve, blocks acetylcholine receptor sites, and decreases bronchial secretions. It is classified as an anticholinergic (parasympatholytic) drug and commonly used to dilate the pupils, increase heart rate, reduce salivation and other secretions, and as an antidote against organophosphate poisoning.

DescriptionAtropine is considered to be the most effective antidote for both OP and CB intoxication. By effectively competing with acetylcholine for the same cellular receptors, it prevents overstimulation of the autonomous parasympathetic system. Most importantly, it helps prevent asphixia, the main cause of death. In human subjects, it is customary to constantly infuse atropine in order to maintain optimal concentration throughout recovery from the “cholinergic crisis.” In wildlife rehabilitation, this is impractical and subjects need to be repeatedly injected with atropine.

HistoryMandragora (mandrake) was described for treatment of wounds, gout and sleeplessness and as a love potion in the fourth century BC by Theophrastus. Atropine extracted from the Egyptian henbane was used by Cleopatra in the last century BC to dilate her pupils in the hope that she would appear more alluring. In the Renaissance, women used the juice of the berries of Atropa belladonna to enlarge the pupils of their eyes for cosmetic reasons. It isn’t until the first century AD that Dioscorides found that wine containing mandrake can be used as an anaesthetic treatment for pain or sleeplessness in surgery or cautery. The combination of extracts containing tropane alkaloids and opium was used to treat diseases, which was popular in the Roman and Islamic Empires and Europe. The combination was replaced by the use of ether, chloroform and other modern anaesthetics about 100years ago. The mydriatic effects of atropine were studied by the German chemist Friedlieb Ferdinand Runge (1795–1867). In 1831, the German pharmacist Heinrich F. G. Mein (1799–1864) succeeded in separating pure atropine from plants. The substance was first synthesized by German chemist Richard Willsttter in 1901. In 1889, Richard Willsttter first confirmed the chemical structure of atropine. Atropine was first synthesized by A.Ladenburg. Homatropine, a kind of tropic alkaline ester, is used in the diagnosis and treatment in ophthalmology, and it has a shorter acting time than atropine. Quaternary ammonium compounds of atropine obtained by alkylation of nitrogen atoms have anticonvulsant function, which does not affect the central nervous system, due to their polarity. In 1970, atropine sulphate was synthesized in Hangzhou, the location of the first pharmaceutical factory in China, which increased the yield, reduced the cost and met the requirements of clinics.

Usesanticholinergic, mydriatic

UsesAtropine is used in medicine and is an antidote for cholinesteraseinhibiting compounds, such as organophosphorus insecticides and certain nerve gases. Atropine is commonly offered as the sulfate. Atropine is used in connection with the treatment of disturbances of cardiac rhythm and conductance, notably in the therapy of sinus bradycardia and sick sinus syndrome. Atropine is also used in some cases of heart block. In particularly high doses, atropine may induce ventricular tachycardia in an ischemic myocardium. Atropine is frequently one of several components in brand name prescription drugs.

UsesScopolamine is found in the leaves of Daturametel L., D. meteloides L., and D. fastuosavar. alba (Cordell 1978). It is used as asedative, a preanesthetic agent, and in thetreatment of motion sickness (Merck 1989).

General DescriptionAtropine is the tropine ester of racemictropic acid and is optically inactive. It possibly occurs naturallyin various Solanaceae, although some claim, with justification,that whatever atropine is isolated from naturalsources results from racemization of (-)-hyoscyamine duringthe isolation process. Conventional methods of alkaloidisolation are used to obtain a crude mixture of atropine andhyoscyamine from the plant material. This crude mixture isracemized to atropine by refluxing in chloroform or by treatmentwith cold dilute alkali. Because the racemizationprocess makes atropine, an official limit is set on thehyoscyamine content by restricting atropine to a maximumlevorotation under specified conditions.Atropine occurs in the form of optically inactive, white,odorless crystals possessing a bitter taste. It is not very solublein water (1:460, 1:90 at 80°C) but is more soluble inalcohol (1:2, 1:1.2 at 60°C). It is soluble in glycerin (1:27),in chloroform (1:1), and in ether (1:25). Saturated aqueoussolutions are alkaline in reaction (pH 9.5). The free baseis useful when nonaqueous solutions are to be made, such asin oily vehicles and ointment bases. Atropine has a plasmahalf-life of about 2 to 3 hours. It is metabolized in the liverto several products, including tropic acid and tropine.