Physiological actions

There is a suspected correlation between the ingestion of sangiunarine and/or chelerj thrine and endemic glaucoma. This subject is extensively 

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CgHijClNjOj. Colourless, hygroscopic, m.p. 2I0-212 C (decomp.). Prepared from fi-chloroethyl carbamate and trimethylamine. It has a physiological action similar to that of acetylcholine, but more prolonged, as it is less readily hydrolysed. It is used for intestinal atony following operations, and can be given orally. 

In addition to chloroform, many other compounds containing the trichloro-methyl group, CI3C-, show marked physiological action. Thus trichloro-acetaldehyde or chloral hydrate, Cl3C CH(OH) (p. 342), and trichloro-tertiary-butanol or chloretone, CUC CfCHaliOH, are both hypnotics. Similarly, tribromo-ethanol or avertin, BraC-CHjOH, has strong anaesthetic properties. 

CCK is found in the digestive tract and the central and peripheral nervous systems. In the brain, CCK coexists with DA. In the peripheral nervous system, the two principal physiological actions of CCK are stimulation of gaU. bladder contraction and pancreatic enzyme secretion. CCK also stimulates glucose and amino acid transport, protein and DNA synthesis, and pancreatic hormone secretion. In the CNS, CCK induces hypothermia, analgesia, hyperglycemia, stimulation of pituitary hormone release, and a decrease in exploratory behavior. The CCK family of neuropeptides has been impHcated in anxiety and panic disorders, psychoses, satiety, and gastric acid and pancreatic enzyme secretions. 

Trigonelline appears to exert no marked physiological action. Ackermann first observed that nicotinic acid administered to dogs appears in the urine as trigonelline. 

Studies on Drug Addiction, with special reference to Chemical Structure of Opium Derivatives and Allied Synthetic Substances and their Physiological Action, by Small, Eddy, Mosettig and Himmelsbach. ... 

Ormosia dasycarpa Jacks. Ormosine, CjoHaaNg, m.p. 85-7°, long needles methiodide (abnormal) picrate, m.p. 178° (dec.). Ormosinine, CjaHaaNj, m.p. 208-5° methiodide, needles, m.p. 245°. Morphine-like in physiological action (Hess and Merck, Ber., 1919, 52,1976). 

The connections between chemical constitution, on the one hand, and colour or physiological action on the other have been continually studied for many years, but the allied property of odour has only engaged occasional attention within quite recent times. 

Very many other examples might be quoted, but these suffice to show that each of the classes of substances quoted has some common inherent characteristic quite apart from questions of volatility, solubility, or physiological action. 

Peroxisome Proliferator-Activated Receptors. Table 4 Summary of the physiological actions of PPAR isotypes and their synthetic ligands... 

Crum Brown A, Frazer TR. On the connection between chemical constitution and physiological action. Part I. On the physiological action of the salts of the ammonium bases, derived from strychnia, brucia, thebaia, codeia, morphia, and nicoti. Trans R Soc Edinburgh 1869 25 151-203. 

In 1868 two Scottish scientists, Crum Brown and Fraser [4] recognized that a relation exists between the physiological action of a substance and its chemical composition and constitution. That recognition was in effect the birth of the science that has come to be known as quantitative structure-activity relationship (QSAR) studies a QSAR is a mathematical equation that relates a biological or other property to structural and/or physicochemical properties of a series of (usually) related compounds. Shortly afterwards, Richardson [5] showed that the narcotic effect of primary aliphatic alcohols varied with their molecular weight, and in 1893 Richet [6] observed that the toxicities of a variety of simple polar chemicals such as alcohols, ethers, and ketones were inversely correlated with their aqueous solubilities. Probably the best known of the very early work in the field was that of Overton [7] and Meyer [8], who found that the narcotic effect of simple chemicals increased with their oil-water partition coefficient and postulated that this reflected the partitioning of a chemical between the aqueous exobiophase and a lipophilic receptor. This, as it turned out, was most prescient, for about 70% of published QSARs contain a term relating to partition coefficient [9]. 

The results from such occluders show that Na channels differ in structure between their internal and external surfaces, have binding sites for a variety of monovalent and divalent cations, and are pharmacologically different despite very similar physiological actions in nerve, muscle, and mammalian cardiac cells. 

An emerging area of interest for the physiological action of the brain of chanokine is the intercellular communication system between neuronal and ghal cells. Indeed, recent in vitro and in situ studies indicated that the chemokines together with then-receptors are constitutively expressed by glial cells and neurons in mature brain (Asensio and Campbell 1999 Cho and Miller 2002 Tran and Miller 2003 Rostene... 

The possibility that drugs developed to protect against other mechanisms of tissue injury might have an additional physiological action because they have antioxidant properties. 

Both the G- and V-agents have the same physiological action on humans. They are potent inhibitors of the enzyme acetylcholinesterase (AChE), which is required for the function of many nerves and muscles in nearly every multicellular animal. Normally, AChE prevents the accumulation of acetylcholine after its release in the nervous system. Acetylcholine plays a vital role in stimulating voluntary muscles and nerve endings of the autonomic nervous system and many structures within the CNS. Thus, nerve agents that are cholinesterase inhibitors permit acetylcholine to accumulate at those sites, mimicking the effects of a massive release of acetylcholine. The major effects will be on skeletal muscles, parasympathetic end organs, and the CNS. 

Another V-agent of interest is Vx, called "V sub x." Another designation for Vx is "V-gas." The properties of Vx are similar to those of VX. It is nearly lOx more volatile than VX, but is very persistent in comparison to the G-agents. The molecular weight of Vx is 211.2. Listed values are calculated, information on this agent is limited. The physiological action, protection, and decontaminants for Vx are the same as for VX. 

The toxicity and the physiological action of insecticides, fungicides, rodenticides, and herbicides on plants are of basic importance. The toxicity of treated plants to animals, and the toxicity of treated plants and animals to humans and to wildlife are of practical concern. A long-range consideration of the effect of sprays on both plant and human nutrition and its relation to public health is of direct concern. The hazards in field application and methods of protecting operators should be reported in detail and further research should be emphasized. 

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