Autonomic nervous system, toxicants affecting

Lithium Mechanism of action uncertain suppresses inositol signaling and inhibits glycogen synthase kinase-3 (GSK-3), a multifunctional protein kinase No significant antagonistic actions on autonomic nervous system receptors or specific CNS receptors no sedative effects Bipolar affective disorder-prophylactic use can prevent mood swings between mania and depression Oral absorption, renal elimination half-life 20 h. narrow therapeutic window (monitor blood levels) Toxicity Tremor, edema, hypothyroidism, renal dysfunction, dysrhythmias pregnancy category D Interactions Clearance decreased by thiazides and some NSAIDs... 

Due to its effect on microtubule assembly, this drug has the ability to arrest mitotic cells in metaphase. Particularly affected are rapidly dividing cells, such as those in skin, hair and bone marrow. In addition, the activity of secretory cells is diminished, as movement of secretory substances out of a secretory cell is inhibited. This could potentially affect all systems in the body (e.g., endocrine systems and systems heavily regulated by the autonomic nervous system). In short, this drug is extremely toxic if administered improperly, and could result in fatality. 

TABLE 7 5. Toxicants Affecting the Autonomic Nervous System... 

The immune system is subject to modulation by a number of environmental cues including, but not limited to, microbial infections, toxic agents, stress, drugs and trauma. Endogenous immunoregulatory factors include those produced by the nervous and endocrine systems. This chapter discusses how these factors, as well as drugs targeting the immune, autonomic and central nervous systems, affect the immune system. 

I. Mechanism of toxicity. PNU is believed to antagonize the actions of nicotinamide and, in a manner similar to that of alloxan and streptozocin, injure pancreatic beta cells. The mechanisms of autonomic neuropathy and central nervous system effects are unknown. Adrenergic neurons acting on blood vessels but not the heart are affected. As a result, orthostatic hypotension associated with an intact reflex tachycardia is the usual picture. 

Toxic agents which affect the peripheral nervous system do so through effects on the synapses of both the autonomic and voluntary systems and by direct actions on peripheral nerves. Military examples include nerve agents and toxins. Civil examples include pesticides and many marine and animal toxins. 

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