Lithium biochemical action

In this age of sophisticated drug design and biotechnolcgy, the simple lithium ion is still the most effective treatment of this destructive psy-cholcgical disorder. Remarkably, in spite of intensive research, scientists still do not fully understand the biochemical action of lithium that leads to its therapeutic effects. Because of its similarity to Na, Li" is incorporated into blood plasma, where it can affect the behavior of nerve and muscle cells. Because Li has a smaller radius than Na (Figure 7.7), the way Li interacts with molecules in human cells is different from the way Na interacts with the molecules. Other studies indicate that Li alters the function of certain neurotransmitters, which might lead to its effectiveness as an antipsychotic drug. 

In this age of sophisticated drug design and biotechnology, the simple lithium ion is stiU the most effective treatment of a destructive psychological disorder. Remarkably, in spite of intensive research, scientists stiU don t fully understand the biochemical action of lithium that leads to its therapeutic effects. 

The first psychotropics of the modern era (e.g., lithium, neuroleptic antipsychotics, tricyclic and monoamine oxidase inhibitor antidepressants) were discovered serendipitously. These agents were not engineered to have selective actions, but instead produce a wide range of central biochemical effects and generally affect more than one neurotransmitter system simultaneously, resulting in multiple repercussions ... 

Schou M. Possible mechanisms of action of lithium salts approaches and perspectives. Biochem Soc Trans 1973 1 81. 

Lithium Compounds Lithium carbonate, which is obtained iiom lithium ore, is the primary source of other lithium compounds. Significant quantities of lithium carbonate are also used in the preparation of porcelain enamels, glazes, and special glass. When purified, the carbonate is used as a source of lithium ion for the treatment of manic-depressive disorders. The physiological action of lithium ion in this treatment is not completely understood, although lithium ion is known to inhibit certain biochemical reactions involved in hormone action. 

Thyroid dysfunction continues to be an infrequent and unpredictable complication found in only 3% of patients according to one review (47 ) and occurring more often in women. A study of the mechanism of action (50 ) in 17 patients on lithium maintenance therapy involved exploration of the hypothalamic-pituitary-thyroid axis. Fourteen subjects showed an exaggerated thyrotropin response to intravenous thyrotropinreleasing hormone that persisted during lithium therapy. However, only 2 of these patients showed any clinical or biochemical evidence of hypothyroidism both showed a delayed recovery of normal TRH response after discontinuing lithium. 

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