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Autism is a neurodevelopmental disorder characterized by presence of social deficits, language abnormalities, stereotypies, and repetitive behavior. Brain pathology is extensive, suggesting widespread dysfunction of neurotransmitter systems. Genetic, biochemical, and gene association studies have shown that a number of neurotransmitters including serotonin, dopamine, oxytocin, GABA and glutamate, and acetylcholine contribute to the pathology of autism. Pharmacological treatment of autism has focused on reduction of symptoms and atypical antipsychotics, antidepressants, mood stabilizers, and anticonvulsants have been shown to successfully reduce many symptoms of autism. In this review we discuss the contributions of neurotransmitter systems to the pathology of autism and pharmacological treatment of autistic symptoms associated with neurochemical dysfunction. [ABSTRACT FROM AUTHOR]

Bipolar disorder (BPD) is a major medical and social burden, but little is known about the specific pathophysiology of BPD. The key biogenic amines in the aminergic system include serotonin (5-HT), norepinephrine (NE), dopamine (DA), and acetylcholine (ACh). By analyzing these neurotransmitters, this chapter highlights three hypotheses in the pathophysiology of BPD: the biogenic amine hypothesis, the cholinergic–aminergic balance hypothesis, and the permissive hypothesis. Evidence from select studies of cerebrospinal fluid, postmortem subjects, neuroimaging, genetic factors, and pharmacological agents will be used to reconcile these hypotheses. Possible explanations for discrepancies in these hypotheses are given, and directions for future studies are suggested. [ABSTRACT FROM AUTHOR]

The neurobiology of eating disorders (EDs) is largely unknown. However, brain imaging studies over the past decade have identified neurotransmitter alterations that could be part of dysfunctional behavior characteristics of EDs. In this chapter we focus on a specific behavioral construct, the brain reward system, and demonstrate a functional brain imaging approach toward identifying dopamine function in anorexia nervosa (AN). We demonstrate how human brain reward activation can be used in a translational approach to test whether computer models, based on basic science research, can predict expected in vivo reward system activation, and how such an approach can identify specific biologic alterations in a psychiatric population. [ABSTRACT FROM AUTHOR]

In this chapter, the basic tools and methods to isolate neurons from the embryonic rat cortex are provided. We outline the isolation of fresh neuronal cells and their storage, post-thaw maintenance, and the application of techniques to measure intracellular calcium changes in response to the addition of neurotransmitters. Many of these techniques come in kit formats supplied by companies like Invitrogen and thus enhance the ease of use, time required, and reproducibility. [ABSTRACT FROM AUTHOR]

Intercellular information transfer in the nervous system is mediated by chemical neurotransmitters. The fidelity of this process requires the rapid release and clearance of the neurotransmitter from the synaptic cleft. In addition to metabolic pathways for synthesis of neurotransmitters, two specific mechanisms, vesicular storage and local reuptake, have evolved to facilitate neurotransmission. These processes are mediated by transporter proteins: vesicular neurotransmitter transporters to fill the vesicles and plasma membrane neurotransmitter transporters to clear the synaptic cleft. This chapter discusses the synthesis, packaging, and recycling of the classic neurotransmitters with an emphasis on the transporter proteins that are integral to these pathways. [ABSTRACT FROM AUTHOR]

Neurobiology is the study and functional organization of the cells that make up the nervous system. The central nervous system (CNS) begins as a simple neural plate that folds to form a groove and then a tube. Then stem cells within the neural tube are directed toward glia and neurons under the influence of various neural developing signaling processes. It is these cells including, but not limited to, neurons, microglia, astrocytes, endothelial cells, their communication and circuitry, one with the other, that lead to our abilities to sense and respond to the environment, think, ambulate, and behave. Neurobiology is at the very interface of biology and neuroscience but is significantly different from each of the fields. Biology is that of all building blocks of cell organization and function regardless of tissue origin. It is broad and without limits. Neuroscience is by its very integration includes works in computation and cognition that are linked to the clinical disciplines of psychiatry and neurology. Each alone or together relate to cell and system analyses and disease. Nonetheless, the disciplines of neuroscience and biology overlap to generate the field of neurobiology. Here there is a central focus on the cell and its functional outcomes. This chapter seeks to describe the discipline of neurobiology starting from the cell and its function to system organization to function. Such processes underlie both nerve cell communication and function as well as the role glial cells can affect the process overall. [ABSTRACT FROM AUTHOR]

The major function of the nervous system is to rapidly transfer and integrate information with a view to organizing the diverse functions of multicellular organisms. Our present understanding as to how nerve cells communicate originates with studies in the nineteenth century on the anatomy of the nervous system. Work conducted by Camillo Golgi and Santiago Ramon y Cajal defined the fine structure of neurons for the first time. Golgi favored the idea that all the nerves in the nervous system existed as a sort of reticular net, rather than as separate entities. Cajal, in contrast, concluded that neurons were independent entities and that a minute gap existed between the ends of nerve fibers and other nerve cells or the muscles that they innervate. This gap was ultimately named a ˵synapse″ by the great neurologist Sir Charles Sherrington in 1897, from the Greek meaning ˵to clasp″. Cajal also argued that neurotransmission was basically a unidirectional process, information being received by dendrites and being transmitted unidirectionally along axons. The actual existence of the synapse as a structure was not confirmed until the development of the electron microscope in the 1950s. Around this time a fierce debate took place between two opposing sets of scientists (Valenstein, 2005). One set, primarily electrophysiologists, held the view that information was transmitted between nerves and between nerves and muscles by purely electrical processes. The other group, primarily pharmacologists, suggested that chemical messenger molecules were released by the presynaptic nerve and carried the information across the synapse. The nature of the chemicals that constitute neurotransmitters was gradually revealed by the work of several important investigators who characterized the effects of different substances that mimicked or blocked the actions of neurotransmitters on fast skeletal muscles and in the autonomic nervous system. This finally culminated in the demonstration by Otto Loewi in 1921 that the vagus nerve secreted a chemical (˵Vagusstoff″) that mediated the slowing effect of vagal stimulation on the heart. This substance turned out to be acetylcholine. [ABSTRACT FROM AUTHOR]

The hippocampus is a brain structure located inside the temporal lobe. It forms a part of the limbic system and plays an important role in the formation, consolidation and retrieval of episodic memories. It has been shown that repetitive activation of excitatory synapses in the hippocampus causes an increase in synaptic strength that last for hours or days designated as long-term potentiation (LTP). It is widely believed that LTP provides an important key to understand the cellular and molecular mechanisms by which memories and formed and stored. Sensory information enters the hippocampus mainly through the perforant pathway consisting of the axons of neurons in layer II and III of the entorhinal cortex. The perforant path axons terminate on the dendrites of the dentate gryus granular cells. Then information flow through the hippocampus from the dentate gyrus to the CA3, the CA1 and the subiculum, forming hippocampal intrinsic trisynaptic circuit. In addition to its ˵traditional″ role in learning and memory, the hippocampus is also involved in neuroimmunity. Lesion of hippocampus alters immunity and neuronal functions in the hippocampus are modulated by a variety of immune active molecules. [ABSTRACT FROM AUTHOR]

Chapter 4 of the book "Psychiatric Mental Health Nursing: Concepts of Care in Evidence-Based Practice" is presented. It explains the functions of cerebrum which comprises the largest part of the human brain. Neurotransmitters are chemicals which are responsible for sending information across synaptic clefts to adjacent target cells. It emphasizes the need for psychiatric nurses to incorporate knowledge of biological sciences to their practices to ensure quality care to mentally ill patients.

A scientist who seeks to explain the actual universe, or any (nonhuman) part of it, in detail as it is, in terms of its concrete history, can properly be called a natural historian - he is literally concerned with the history of nature. The natural philosopher on the other hand is devoted to the search for fundamental laws of the highest possible generality – laws which he hopes will apply throughout space and time. For the natural historian, the laws of natural philosophy are not ends in themselves, but tools for the understanding of the actual universe … The mode of thought typical of the natural historian … is much more akin to that of Sherlock Holmes than to those of Newton, Einstein, Bohr or Rutherford. I began Chapter 1 of this book with an epigraph from Crowson 's book on taxonomy, and I again quote from him in the final chapter. The distinction between Natural History and Natural Philosophy is not a new one. It is (or was) embodied in the titles of professorial chairs in the ancient Scottish universities, meaning Zoology (or Biology) and Physics, respectively, and can be regarded as explicit at the beginning of the systematic study of the Philosophy of Science. Bacon, as Crowson points out, coined the terms in his De Dignitate et Augmentis Scientiarum (1623). [ABSTRACT FROM AUTHOR]