Central nervous system drug actions

This review will focus on the potential biological impact of two classes of pharmaceuticals prevalent in the environment because of their wide therapeutic use lipid regulators and central nervous system drugs. This should serve as a foundation for future studies on the mechanism of action of these pharmaceuticals in non-target species and as a warning of the next wave of endocrine disrupting substances that we are adding to our environment continuously. 

Although it has been clinically available for a number of years, the United States Food and Drug Administration in early 1968 allowed labeling changes for diazepam (XXIV) to allow for new indications of use for the relief of muscle spasm and adjunctive use in convulsive disorders . It was reported that in cats the brain stem reticular system is the major locus of central nervous system depressant action of this centrally acting skeletal muscle relaxant. 

Omission of the side chain hydroxyl group from molecules based on epinephrine or ephedrine does not abolish the sympathomimetic activity of the resulting compounds. Many of these agents exert a considerable stimulant action on the central nervous system. As such, drugs in this class have been widely used—and... 

All barbiturates have essentially die same mode of action. Depending on the dose given, tiiese drags are capable of producing central nervous system (CNS) depression and mood alteration ranging from mild excitation to mild sedation, hypnosis (sleep), and deep coma These drugs also are respiratory depressants the degree of depression... 

Discuss the uses, general drug actions, general adverse reactions, contraindications, precautions, and interactions of the central nervous system stimulants. 

These drug have a rapid onset and a short duration of action. They depress the central nervous system (CNS) to produce hypnosis and anesthesia but do not produce analgesia. Recovery after a small dose is rapid. 

The various stimulants have no obvious chemical relationships and do not share primary neurochemical effects, despite their similar behavioral effects. Cocaines chemical strucmre does not resemble that of caffeine, nicotine, or amphetamine. Cocaine binds to the dopamine reuptake transporter in the central nervous system, effectively inhibiting dopamine reuptake. It has similar effects on the transporters that mediate norepinephrine and serotonin reuptake. As discussed later in this chapter in the section on neurochemical actions mediating stimulant reward, dopamine is very important in the reward system of the brain the increase of dopamine associated with use of cocaine probably accounts for the high dependence potential of the drug. 

Neurotransmitter receptors have evolved as one of the key components in the ability of the central nervous system to coordinate the behaviour of the whole animal, to process and respond to sensory input, and to adapt to change in the environment. These same receptors are therefore ideal targets for drug action because of their central role in the activity of the nervous system. A rational approach to the development of new therapeutic strategies involving the action of drugs at receptors in the nervous system is based on knowledge of receptor structure, distribution and function. 

Carvey PM (1998). Drug Action in the Central Nervous System (pp. 279-309). Oxford University Press, New York. 

Pirsidomine 135 has antiischaemic and antianginal properties, and is similar in action to molsidomine, undergoing bioactivation in vivo to compound 136 <1996MI4937>. Sydnocarb (mesocarb) 59 acts on the central nervous system (CNS) and has been used as a psychotropic drug and antidepressant <2004CHE507>. 

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