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Hypothalamus nerve cells

Hydroxy tryptamine, or serotonin, is a neurotransmitter in the central nervous system (CNS). The nerve-cell bodies of the major serotoninergic neurones are in the midline raphe nuclei of the rostral pons, and ascending fibers innervate the basal ganglia, hypothalamus, thalamus, hippocampus, limbic forebrain, and areas of the cerebral cortex. The serotoninergic system plays an important role in the control of mood and behavior, motor activity, hunger, thermoregulation, sleep, certain hallucinatory states, and some neuro-endocrine mechanisms. [Pg.73]

The endocrine system is controlled by the brain. Nerve cells of the hypothalamus synthesize and release messenger substances that regulate adenohy-pophyseal (AH) hormone release or are themselves secreted into the body as hormones. The latter comprise the so-called neurohypophyseal (NH) hormones. [Pg.242]

The posterior pituitary gland is the source of circulating oxytocin and vasopressin (iantidiuretic hormone, ADH). These hormones are actually produced in specific nerve cells in the hypothalamus and travel down the axons into the neuro-hypophysis. The structures of oxytocin and vasopressin are shown in Chapter 4. It may be seen that both are nanopeptides with disulfide bonds and that they differ by two amino acids only. Both hormones originate from larger proteins vasopressin from prepressophysin and oxytocin from pro-oxyphysin. These are converted to pressophysin and oxyphysin, respectively (collectively,... [Pg.397]

Grossman SP, Dacey D, Halaris AE, Collier T, Routtenberg A (1978) Aphagia and adipsia after preferential destruction of nerve cell bodies in hypothalamus. Science 202 537-539. [Pg.287]

Sakanaka M, Magari S, Inoue N, Lederis K (1990b) Co-localization of arginine vasopressin- and enkephalin-like immunoreactivities in nerve cells of the rat hypothalamus. Cell Tissue Res 260 549-554. [Pg.517]

The endocrine system is controlled by the brain. Nerve cells of the hypothalamus... [Pg.238]

The primary stimulus for oxytocin release is suclding. Stimulation of tactile receptors located around the nipples of the breasts initiates an action potential that propagates along afferent nerve fibers through the spinal cord and mid-bram to the hypothalamus. The cell bodies in the paraventricular nucleus are then stimulated, resulting in the episodic release of oxytocin. Stretch receptors in the uterus and possibly in the vaginal mucosa may also initiate action potentials in afferent nerve fibers that ultimately stimulate the release of oxytocin from the neurohypophysis. Estrogens enhance the response of oxytocin to these stimuli. The influence of other parts of the brain on the release of oxytocin has been reported emotional stress, for instance, inhibits lactation. [Pg.1996]

In contrast to some hormones that have to travel considerable distances in order to stimulate their target cells, neurotransmitters have only to cross the gap or synaptic cleft, a distance of a few nanometres, from the nerve cell to the target cell. The release of TRH from the hypothalamus is triggered by the arrival of a neurotransmitter from an adjacent neurone. There are various types of neurone, sensory ones, intemeurones and motor neurones that collect and transmit information about the ambient temperature, light input to the eye, pain etc. to the brain, which may then transmit a message to motor neurones, for example, in order to effect removal of one s finger from a hot object. [Pg.202]

The organization of the endocrine system can best be described in relation to the central nervous system. Three levels of endocrine tissues can be distinguished on the basis of their association with the central nervous system (Figure 30-12). The first level consists of those that are (or were) derived from nerve cells these include the hypothalamus, adrenal medulla, thyroid C-cell, and gastrointestinal enterochromaffin cells. The hypothalamus and adrenal medulla still retain their neural connections and can therefore be regarded as endocrine extensions of the nervous system. The C-cell and the gut cells, however, are APUD cells and lack neural connections. These four tissues produce hormonal peptides or amines having, like neurotransmitters, rapid-onset, short-term effects. [Pg.723]

The hypothalamus contains a high density of nerve cell bodies clustered into nuclei or areas. Neurons in each of these nuclei tend to send their axons to the same regions in the form of traets. These nuclei innervate the median eminence, other hypothalamic nuclei, the posterior pituitary, and various structures in the extrahy-pothalamic central nervous system. All of the hypothalamic neurons are presumably monoaminergic (i.e., they... [Pg.729]

The hormonal system is closely related to the nervous system. Adrenaline, for example, is not only a hormone but also a neurotransmitter in the synaptic cleft of nerve cells. Both systems serve the coordination of bodily functions and are centrally connected via the hypothalamus (Fig. 6.2). [Pg.520]

Although mast cells and basophils probably account for >90% of stored histamine in the body, histamine is also present in platelets, enterochromaffin-like cells, endothelial cells, and neurons. Histamine can act as a neurotransmitter in the brain. Histaminergic nerves have their cell bodies within a very small area of the brain (the magnocellular nuclei of the posterior hypothalamus) but have axons in most areas of the forebrain. There is also evidence for axons projecting into the spinal (Fig. 1) cord. Finally, there is evidence that histamine synthesis can be induced in tissues undergoing rapid tissue growth and repair. In certain neonatal tissues (e.g. liver), the rate of synthesis of this unstored diffusable histamine (termed nascent histamine) is profound and may point to a role for histamine is cell proliferation. [Pg.588]

As discussed previously, the neurohypophysis has a direct anatomical connection to the hypothalamus. Therefore, the hypothalamus regulates the release of hormones from the neurohypophysis by way of neuronal signals. Action potentials generated by the neurosecretory cells originating in the hypothalamus are transmitted down the neuronal axons to the nerve terminals in the neurohypophysis and stimulate the release of the hormones into the blood. The tracts formed by these axons are referred to as hypothalamic-hypophyseal tracts (see Figure 10.2). The action potentials are initiated by various forms of sensory input to the hypothalamus. Specific forms of sensory input that regulate the release of ADH and oxytocin are described in subsequent sections in this chapter. [Pg.121]


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See also in sourсe #XX -- [ Pg.238 ]




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