Altered neurochemistry

There have been some studies attempting to link normal or drug-induced behaviour with brain neurochemistry. As yet these studies (Memo et al., 1980a Rafales et al., 1981) have largely failed to relate behavioural changes to altered neurochemistry, although one report (Lucchi etal., 1981) has made limited correlation. 

Roth SH, Skrajny B, Reiffenstein RJ. 1995. Alteration of the morphology and neurochemistry of the developing mammalian nervous system by hydrogen sulphide. Clin Exp Pharmacol Physiol 22 379-380. 

Initiation and Adaptation. The answer to this question is surprisingly simple. Many psychiatric medicines do not work immediately because they work indirectly. By changing neurotransmission, these medicines set in motion a sequence of events in the brain. As brain neurochemistry gradually changes in response to the sustained alterations in neurotransmission produced by the psychiatric medicine, the therapeutic effects of the medication become evident. Taking the medication initiates the process, but the adaptation made by the brain to the continued presence of the medication is what ultimately determines whether or not there is a response. 

The alterations in neurotransmitter activity which trigger or accompany the onset of natural sleep and distinguish slow wave or non-REM from REM sleep, provide one of the most compelling arguments in favour of chemical neurotransmission being specifically involved in mechanisms of conscious awareness. For an extensive review on neurochemistry and sleep, see Gottes-man (1999). 

Farooqui A. A. and Horrocks L. A. (2007a). Glutamate and cytokine-mediated alterations of phospholipids in head injury and spinal cord trauma. In Banik N. (ed.), Brain and Spinal Cord Trauma. Handbook of Neurochemistry. Lajtha, A. (ed.). Springer, New York, in press. 

Thomas AJ, Erokwu BO, Yamamoto BK, Emsberger P, Bishara O, Strohl KP. Alterations in respiratory behavior, brain neurochemistry and receptor density induced by pharmacologic suppression of sleep in the neonatal period. Brain Res Dev Brain Res 2000 120 181-189. 

Other factors can lead to alcoholism, too. Family, school, workplace, and community conditions may play a part. The drug itself may be a major factor, since it can alter the body s neurochemistry and instill craving. Some people progress very quickly from social drinking to alcoholism, while others develop the disease over a period of decades. —... 

Evaluation of neurotoxicity of a chemical substance is dependent on several parameters—for instance, changes in neurochemistry, anatomy, physiology, and or the behavior of the poisoned animal or human. Also, alterations in sensory processes such as paresthesia and visual, olfactory, and or auditory impairments have been often indicated as symptoms of neurotoxicity observed among workers exposed to different toxic substances in workplaces. ... 

HerouxM and Butterworth RF (1995) Regional alterations of thiamine phosphate esters and of thiamine diphosphate-dependent enzymes in relation to function in experimental Wernicke s encephalopathy. Neurochemistry Research 20,87-93. 

Perinatal exposure of mice to dieldrin alters the dopaminergic neurochemistry in their offspring. Exposure to a mixture of dieldrin and MPTP during development exacerbates the neurotoxicity of MPTP, a known chemical cause of Parkinson s disease. This study serves as a model for the induction of Parkinson s disease by chemical mixtures. I26l... 

Begley, J.G. et al., 1999. Altered calcium homeostasis and mitochondrial dysfunction in cortical synaptic compartments of presenilin-1 mutant mice. Journal of Neurochemistry, 72(3), pp. 1030-1039. 

Potential modes of action for lead neurotoxicity include oxidative stress, inhibition of enzymes needed for energy production, decreased levels of neurotransmitters and altered neurotransmitter release, and increased permeability of the blood-brain barrier (EPA 2012). Ultimately, lead-induced neurotoxicity in adults consists of changes in brain stracture and neurochemistry, including white-matter changes, reduction in gray matter, and alterations in brain metabolites. 

Although it is possible to measure certain neurochemical parameters in humans, the understanding of molecular mechanisms of lead toxicity must depend on animal experimentation. Alterations in neurochemistry may precede other neurotoxic effects and be the basis for the expressions of altered behaviour, pharmacological response or cell pathology. 

Beauchesne, E., Desjardins, P., Flazell, A.S., and Butterworth, R.F., 2009. Endothelial NOS mediates blood-brain barrier alterations in the thiamine-deficient mouse brain. Journal of Neurochemistry. Ill 452—459. 

Normal structure and function of the brain are altered by severe and/or long-term stress [reviewed in 236]. The hippocampus is among the brain s regions most vulnerable to stress-related adverse changes [reviewed in 237]. Stress negatively impacts hippocampal neuronal excitability, neurochemistry, and structural and functional plasticity [236, 238]. This has been demonstrated in both animal... 

Silbergeld, E.K., Lamon, J.M., 1982. Effects of altered porphyrin synthesis on brain neurochemistry. Neurobehav. Toxicol. Teratol. 4, 635—642. 

Brown, M. L., Marshall, L. A., Johnston, P. V., 1984 Alterations in cerebral and microvascular prostaglandin synthesis by manipulation of dietary essential fatty acids. J. Neurochemistry 43, 1392-1400. 

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