Central nervous system, drugs acting antidepressants

Katzung PHARMACOLOGY, 9e > Section V. Drugs That Act in the Central Nervous System > Chapter 30, Antidepressant Agents > ... 

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>. 

Serotonin mediates many central and peripheral physiological functions, including contraction of smooth muscle, vasoconstriction, food intake, sleep, pain perception, and memory, a consequence of it acting on several distinct receptor types. Although 5-HT may be metabolized by monoamine oxidase, platelets and neurons possess a high-affinity mechanism for reuptake of 5-HT. This mechanism may be inhibited by the widely prescribed antidepressant drugs termed selective serotonin re-uptake inhibitors (SSRl), e.g. fluoxetine (Prozac ), thereby increasing levels of 5-HT in the central nervous system. 

Drugs and chemicals are known to cause activated interaction. The depressant action of opioid drugs is enhanced by drugs acting on the central nervous system (CNS) such as alcohol, anesthetics, anxiolytics, hypnotics, tricyclic antidepressants, and antipsychotics. Concomitant administration of opioid analgesics and monoamine oxidase inhibitors (MAOIs) should be avoided, or extra care should be taken if such a therapy is inevitable. Fatal reactions are reported when treated along with selegiline. Interactions also are reported with cyclizine, cimetidine, mexiletine, cisapride, metoclopramide, or domperidone. 

Drugs that act on the central nervous system include, amongst others, antidepressant, anti-seizure and sedative drugs. Pharmaceuticals from these classes have been found in aquatic environments13,33 and are of interest because they have the potential to be endocrine disruptors although for the most part this hypothesis has yet to be tested in any aquatic species. To illustrate the possible endocrine disrupting effects, first it will be necessary to briefly describe several aspects of the fish neuroendocrine system. 

Antidepressant drugs elevate levels of key neurotransmitters in the central nervous system (CNS), such as norepinephrine and serotonin, which have been shown to have effects in mood elevation. Alternatively, these drugs may also act as agonists at the receptor level. 

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