Carbamate anticholinesterase

Sherby SM, Eldefrawi AT, Albuquerque EX, Eldefrawi ME. Comparison of the actions of carbamate anticholinesterases on the nicotinic acetylcholine receptor. Molec. Pharmacol. 27 343-348, 1984. 

Carbamate anticholinesterase agents are carbamic acid esters that are hydrolyzed by AChE in a manner similar to that of ACh. Carbamates have this general structure ... 

Recalling that parathion was developed as an insecticide by aayer in 1944 and that the Geigy Company were developing the carbamate anticholinesterases for this purpose in the late 1940s, we see that the 1950s were entered with (including toxaphene) no less than four new classes of chlorinated insecticides and two new classes of anticholinesterase insecticides - a truly unique situation ... 

Green, A.L. (1983). A theoretical kinetic analysis of the protective action exerted by eserine and other carbamate anticholinesterase against poisoning by organophosphorus compounds. Biochem. Pharmacol. 32 1717-22. 

Carbamate anticholinesterases these are reversible in as much as their duration of action is short as compared to organophosphorus anticholinesterases, and are used extensively. An example is carbaryl (carbaril) and several analogues of carbaryl are used as insecticides. However, not all carbamates found in garden formulations are cholinesterase inhibitors the dithiocarbamates are fungicidal. 

Ballantyne, B., Local and systemic pharmacology and toxicology of organophosphate and carbamate anticholinesterases, in Toxicology of Organophosphate and Carbamate Compounds, Gupta, R.C., Ed., Elsevier, Amsterdam, 2006c, pp. 423 445. 

Reversible carbamate anticholinesterase and allosteric modulator at nicotinic cholinergic receptor sites potentiating nicotinic neurotransmission. Originally derived from the bulbs of the Caucasian snowdrop (Galanthus woronowii), now prepared synthetically for clinical use in the treatment of Alzheimer s disease. 

Pretreatment. Carbamate anticholinesterases, e.g., pyridostigmine, may be used as pretreatments against nerve agent poisoning. For further information see Chapter 2 of FM 8-9 (Part III). 

The carbamate anticholinesterases such as PB bind reversibly with ChE enzyme, yet spontaneously reactivate relatively rapidly. However, nerve agents (organophosphate compounds) bind with the ChE irreversibly and form a much more stable phosphory-lated enzyme (ChE-OP) complex. PB binds to peripheral ChE at anionic and esteratic sites and thus carbamylates the enzyme. The carbamylated enzyme sites cannot bind with nerve agents. In the meantime, some of the nerve agents are hydrolyzed to inactive metabolites by nonspecific hydrolases. The decarbamylation of the ChE takes place at the alcohol moiety on the esteratic site, regenerating the ChE enzyme to sustain life. 

Occupational Toxicology and Occupational Hygiene Aspects of Organophosphate and Carbamate Anticholinesterases with Particular Reference to Pesticides ... 

Propoxur(o-lsopropoxyphenyl AFmethylcatbamale, DDVP, Baygon [CAS 114-26-1]) A carbamate anticholinesterase insecticide (see p 291), Limited evidence foradverse effects on fetal development in test animals, 0.5 mg/m A3 White crystalline solid with a faint characteristic odor. Vapor pressure is 0.01 mm Hgat120°C (248°F). Common insecticide found in many OTC formulations. 

Conventionally, NA poisoning is treated by a combi-nahon of prophylactic and post-exposure therapy, which target the three post-exposure phases of neurotransmitter systems described. Prophylactic treatments are designed to circumvent aging of e NA-AChE complex and consist of carbamate anticholinesterases (e.g., pyridostigmine)... 

Physostigmine (a naturally occurring carbamate anticholinesterase compound extracted from the Calabar bean) may be used as an antidote to the effects of BZ. It should be administered intravenously with care in severely affected patients in doses of 2-4 mg given at hourly intervals. 

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