Dopamine neurochemistry

The sites of action of drugs affecting the dopamine synapse are indicated in Fig. 7.3. Those modifying the synthesis, storage, release, uptake and metabolism of DA have been covered above in the appropriate sections on neurochemistry. The actions and uses of agonists and antagonists are outlined in Table 7.4 and covered in detail in appropriate chapters. Their structures are given in Fig. 7.6. 

Another way of viewing it would be as levers going off Serotonin is inhibitory, dopamine is excitatory. That is naive, but there is evidence to suggest that in the neurochemistry of those compounds there has been a kind of yin and yang. 

There are several ways in which possible neurotoxic effects might be studied. First, measurement of cerebrospinal fluid concentrations of dopamine or serotonin metabolites would be a straightforward way of assessing neurotoxicity. There are pitfalls in this approach (as outlined by Dr. Ricaurte (this volume), such as the facts that lumbar cerebrospinal fluid might reflect spinal cord neurochemistry more than it reflected brain neurochemistry, and drugs like /r-chloroamphetamine affect serotonin neurons in spinal cord less than they do those in brain (Sanders-Bush... 

Sixteen years later, when the first edition of Basic Neurochemistry appeared, Sol Snyder s chapter could classify norepinephrine, dopamine and serotonin as... 

Pehek EA, Schechter MD, Yamamoto BK. (1990). Effects of cathinone and amphetamine on the neurochemistry of dopamine in vivo. Neuropharmacology. 29(12) 1171-76. 

Dopamine plays a key role in the regulation of cognition (Chapters 10 and 17) and control of movement. Given the abnormalities in these domains in mental retardation, any association between dopamine and mental retardation may be relevant to the neurochemistry of consciousness, especially relating to cognition. 

Salamone, J.D. (1996) The behavioral neurochemistry of motivation methodological and conceptual issues in studies of the dynamic activity of nucleus accumbens dopamine. / Neurosci Methods 64 137-149. 

Grace, T. (2000) Cellular and molecular neurochemistry of psychostimulant effects on dopamine. In Solanto, M. and Castellanos, X., eds. The Neuropharmacology of Psychostimulant Drugs Implications for ADHD, 1st ed. New York Oxford University... 

J. Zigmond. 1989. "Differential Effect of Stress on In-Vivo Dopamine Release in Striatum, Nucleus Accumbcns, and Medial Frontal Cortex." journal of Neurochemistry 52 1655-58. 

Acquas, Elio, and Gaetano Di Chiara. 1992. "Depression of Mesolimbic Dopamine Transmission and Sensitization to Morphine During Opiate Abstinence." Journal of Neurochemistry 58 1620-25. 

Parsons, Loren H., and Joseph B. Justice Jr. 1993. "Serotonin and Dopamine Sensitization in the Nucleus Accumbens, Ventral Tegmental Area, and Dorsal Raphe Nucleus Following Repeated Cocaine Administration." Journal of Neurochemistry 61 1611-19. 

Pettit, Hugh O., Hwai T. Pan, Loren H. Parsons, and Joseph B. Justice Jr. 1990. "Extracellular Concentrations of Cocaine and Dopamine Are Enhanced During Chronic Cocaine Administration." fournal of Neurochemistry 55 798-804. 

However, the exact problem in CNS amine neurotransmission remains a subject of much debate. One leading theory is that depression may be caused by an increased sensitivity of the presynaptic or postsynaptic receptors for these transmitters. That is, the neurochemistry of the brain has been changed in some way to make the amine receptors more sensitive to their respective amine neurotransmitters (norepinephrine, serotonin, and to a lesser extent, dopamine).21 This theory is based primarily on the finding that antidepressant drugs prolong the activity of amine neurotransmission in the brain, thereby causing a compensatory decrease in the sensitivity of the amine receptors.21,47... 

Gottesmann C. The neurochemistry of waking and sleeping mental activity the dis-inhibition-dopamine hypothesis. Psychiatr Clin Neurosci 2002 56 345-354. 

Bungay PM, Newton-Vinson P, Isele W, Garris PA JusticeJrJB. Microdialysis of dopamine interpreted with quantitative model incorporating probe implantation trauma, journal of Neurochemistry 2003, 86, 932-946. 

Dopamine is a neurotransmitter that has long been of interest to both chemists and neuroscientists. For instance, a loss of dopamine-containing neurons or its transmission is related to a number of illnesses and conditions including Parkinson s disease and schizophrenia. It is therefore of interest to perform quantitative and qualitative determination of dopamine in the extracellular fluid in animals in order to gain an understanding of the neurotransmission processes. Such a study will also aid in correlating neurochemistry with behaviour. 

Among the catecholamines, dopamine has long been of interest to both chemists and neuroscientists. It is one of the most important neurotransmitters and is ubiquitous in the mammalian central nervous system[5]. It modulates many aspects of brain circuitry in a major system of the brain including the extra pyramidal and mesolimbic system, as well as the hypothalamic pituitary axis[6]. It also plays a crucial role in the functioning of the central nervous, cardiovascular, renal and hormonal systems[4], A loss of dopamine containing neurons or its transmission is also related to a number of illnesses and conditions including Parkinson s disease, schizophrenia, motivational habit, reward mechanisms and the regulation of motor functions and in the function of the central nervous, hormonal and cardiovascular system[5,18,19]. It is therefore of interest to measure dopamine in the extracellular fluid in animals to order to monitor neurotransmission processes and correlate neurochemistry with behavior[19]. 

Sacchetti, P., Mitchell, T.R., Granneman, J.G. and Bannon, M.J. (2001) Nurrl enhances transcription of the human dopamine transporter gene through a novel mechanism. Journal of Neurochemistry, 76, 1565—1572. 

J.L. Cadet and C. Brannock, Free radicals and the pathobiology of brain dopamine systems. Neurochemistry International, 32(2), 117-131 (1998). 

Opiates snch as morphine and codeine are thonght to enhance the release by nenrons of the nenrotransmitter dopamine the release of dopamine leads to a sense of enphoria. These drugs are addictive and are often abused. In general, all antipsychotic medications work by blocking dopamine receptors in the forebrain. Nicotine mimics the action of the nenrotransmitter acetylcholine at receptors having to do with the transmission of signals between antonomic nerve cells and skeletal muscle, see also Caffeine Epinephrine Methylphenidate Neurochemistry Neurotransmitters Norepinephrine. 

In particular, neurochemistry has found CE especially useful for quantifying neurotransmitter concentrations in single cells. Since important cellular processes such as neurotransmitter synthesis, storage and release are affected by the cytoplasmic concentrations of neurotransmitters, methods to sample and quantify cytoplasmic concentrations of neurotransmitters from single invertebrate cells have been developed. Invertebrate neurons are particularly amenable for sampling because they can be quite large, for example, the giant dopamine neuron of pond snails is 200 p,m... 

---