Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.14.16.2 (tyrosine hydroxylase)
 14,760 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A study was made of the distribution of sympathetic preganglionic neurons identified by retrograde labeling with horseradish peroxidase from various peripheral nerve trunks and of the distributions of monoaminergic terminals in the spinal cord of the rat. Nerve terminals were stained immunohistochemically by using antisera raised against tyrosine hydroxylase, phenylethanolamine-N-methyl-transferase, neuropeptide Y, and 5-hydroxytryptamine and by using formaldehyde-induced fluorescence. The three-dimensional distribution of sympathetic preganglionic neurons was described by using computer reconstruction and compared with the arrangement of each population of immunohistochemically stained terminals in the intermediate zone. Although monoaminergic terminals are associated with most sympathetic neurons, particularly in the intermediolateral column, the relationship of many terminals to sympathetic neuron somata in other parts of the intermediate zone is tenuous. Some of the descending innervation may terminate on interneurons. The data are consistent with the coexistence of phenylethanolamine-N-methyl-transferase and neuropeptide Y in terminals arising from cell bodies in the C1 region in the ventrolateral medulla and with the presence of at least two populations of catecholaminergic terminals as well as the adrenergic one. Serotoninergic terminals are denser and have a different arrangement from those of catecholaminergic terminals in the intermediate zone.
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PMID:Distribution of sympathetic preganglionic neurons and monoaminergic nerve terminals in the spinal cord of the rat. 256 44

The distribution of dopamine-containing cell bodies and fibers was studied with aid of specific antibodies against dopamine in the highly developed brain of the weakly electric fish Gnathonemus petersii. In the telencephalon, dopamine-containing cell bodies were observed in a small area, i.e., area ventralis pars dorsalis and supracommissuralis. In the diencephalon, moderate numbers of dispersed dopamine-immunoreactive cells were present in the preoptic region, while large numbers of dopamine-containing neurons occurred in the hypothalamic paraventricular organ and neighbouring regions. The paraventricular organ, located around small (anterior, intermediate, and posterior) recesses contained many dopamine-immunoreactive cerebrospinal fluid-(CSF)-contacting neurons. Dopamine-containing cells were also observed in a magnocellular hypothalamic cell group, in the nucleus of the lateral recess, and in the nucleus posterior tuberis. In the mesencephalon only a few dopamine-containing cells were observed in a dorsal tegmental (possibly pretectal) area, whereas in ventral mesencephalic regions dopamine-containing cells were lacking. More caudally, dopamine-containing cells were observed in the presumed locus coeruleus, in the caudal region of the reticular formation, and in the presumed area postrema. Dopamine-immunoreactive fiber density was very high in the medioventral hypothalamus and in the preoptic region, where a dense subependymal plexus was observed along the preoptic recess. Such a plexus was also present in the caudal rhombencephalon, where it probably arises from the area postrema. Moderate numbers of dopamine-immunoreactive fibers were present in medioventral parts of the brain along its total rostrocaudal extent as well as in several subnuclei of the torus semicircularis, in the tectum mesencephali, and in the medial part of the dorsal telencephalic area. Other parts of the dorsal telencephalic area, as well as the large cerebellum and the electrosensory lateral line lobe of Gnathonemus, did not contain detectable amounts of dopamine. In spite of the high differentiation of the brain of Gnathonemus, the distribution of catecholamines as visualized with dopamine immunohistochemistry appears to be basically similar to that described in other teleostean and actinopterygian fishes on the basis of formaldehyde-induced fluorescence or tyrosine hydroxylase immunohistochemistry.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Distribution of dopamine immunoreactivity in the brain of the mormyrid teleost Gnathonemus petersii. 270 53

Assay of catecholamines in guinea-pig lung showed that the amount of dopamine in this tissue is 3-4 times greater than that predicted to be associated only with noradrenergic nerves, and is depleted by animal treatment with 6-hydroxydopamine. Fluorescence microscopy after formaldehyde condensation did not reveal any non-neuronal stores of catecholamines within the lung. The pulmonary and bronchial arterial vessels are accompanied by numerous fine nerve fibres that exhibit immunoreactivity for tyrosine hydroxylase, and are therefore presumed to be catecholaminergic. A small proportion of these fibres are also immunoreactive for DOPA decarboxylase. The results are consistent with innervation of pulmonary and bronchial resistance vessels by dopaminergic as well as noradrenergic sympathetic axons.
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PMID:Evidence that blood vessels in guinea-pig lung are supplied by both noradrenergic and dopaminergic axons. 272 36

Although the anatomical localization and distribution of the neurotransmitter, dopamine, has been extensively studied in the vertebrate central nervous system, the cell bodies of neurons which synthesize and store this transmitter were not thought to be present in the spinal cord. Using the formaldehyde-glutaraldehyde (Faglu) method for the fluorescent visualization of catecholamines, and immunohistochemistry with antisera to the catecholamine synthetic enzymes, we have found in primary cultures of mouse and rat spinal cord three morphologically distinct types of intrinsic spinal cord neurons that contain a catecholamine and the rate-limiting enzyme for catecholamine synthesis, tyrosine hydroxylase (TH).
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PMID:Morphological and histochemical characterization of three types of dopamine-containing neurons in primary cultures of mouse and rat spinal cord. 287 67

The axonal transport of adrenergic and cholinergic axonal organelles in rat sciatic nerve has been studied using a cytofluorimetric scanning (CFS) technique. This technique gives quantitative data on material which accumulates in a nerve relative to a crush, as well as morphological and morphometrical information about the accumulated axons in the nerve. One important advantage is that several substances can be measured in the same nerve segment, thus reducing the number of animals needed. The substances must be made fluorescent, and in this study we have investigated noradrenaline (NA), using formaldehyde induced fluorescence, and dopamine beta-hydroxylase (DBH), tyrosine hydroxylase (TH), neuropeptide Y (NPY) and two cholinergic vesicle components (a transmembrane glycoprotein and synapsin I) using indirect immunofluorescence. The antisera used for labelling immunoreactive material (IR) were produced in rabbit or goat (DBH). In adrenergic axons NA, DBH-IR and TH-IR accumulated with time after crushing the nerve as described earlier with biochemical techniques. After reserpine, the amounts of amine granules transported distally in the sciatic nerve initially fell, but recovered during day 2 after reserpine. At day 4 the amount of NA and DBH-IR which was transported distally in the axons was supranormal, 160% and 140% of control, respectively, but the level of NPY-IR was not increased, even falling to subnormal at day 4, indicating different mechanisms for regulating the synthesis of DBH and NPY which are suggested to co-exist in axonal adrenergic large dense core vesicles. In cholinergic motor axons organelles, recognized by rabbit-anti-cholinergic synaptic vesicles-antiserum (RASVA) and by anti-synapsin I-antiserum, are transported distally at a rapid rate.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Immunocytochemical studies on axonal transport in adrenergic and cholinergic nerves using cytofluorimetric scanning. 287 31

Contrary to traditional teaching, mammalian primary sensory neurons may express catecholaminergic (CA) neurotransmitter characteristics in vivo. Sensory neurons in the nodose, petrosal, and dorsal root ganglia of rats express tyrosine hydroxylase, the rate-limiting enzyme in CA biosynthesis, and formaldehyde-induced CA fluorescence, in addition to other CA traits. These findings suggest that catecholamines may function as sensory as well as autonomic motor (e.g., sympathetic) neurotransmitters. Most CA cells in the petrosal ganglion project peripherally to the carotid body, which indicates a striking correlation between CA expression in sensory neurons and the pattern of sensory innervation. Inasmuch as petrosal ganglion afferents make synaptic contact with chemoreceptive glomus cells in the carotid body, it is likely that CA sensory neurons in the ganglion transmit chemoreceptor information to the brain stem. Comparison with sympathetic neurons indicates that some mechanisms of CA regulation, such as altered activity of tyrosine hydroxylase in response to depolarizing stimuli, are shared among sensory and traditional CA populations. Other mechanisms, including trophic regulation, appear to be distinct. Therefore, despite expression of common phenotypic traits, CA expression in diverse populations of peripheral neurons is not necessarily associated with a common repertoire of regulatory mechanisms.
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PMID:Catecholaminergic primary sensory neurons: autonomic targets and mechanisms of transmitter regulation. 287 46

The prenatal and postnatal development of the rat retroperitoneal paraganglia were studied using the formaldehyde-induced catecholamine fluorescence (FIF) method. In addition, the transmitter composition of the paraganglionic cells of the newborn rat was analyzed by immunohistochemical demonstration of the catecholamine-synthesizing enzymes. The first fluorescent preaortic cells were detected in the 13.5-day-old embryos. One day later these cells constituted a distinct organ with moderately fluorescent cells, and in 15.5-day-old embryos this organ consisted cranially of moderately fluorescent and caudally of brightly fluorescent cells. The organ reached its largest size at birth and afterwards fibrous material increased between the fluorescent cells. In 4-week-old animals, only small clusters of fluorescent cells were observed in the preaortic area although many small paraganglia were situated cranially near the coeliac ganglion. In the organ of the newborn rat, many cells showed bright FIF. In addition, some cells with only slight or moderate fluorescence as well as non-fluorescent cells were detected. The analysis of immunoreactivity to the catecholamine-synthesizing enzymes showed that there was a cell population with intense reactivity to both tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH). These cells were considered as paraganglion-type cells. Some of them were also immunoreactive to phenylethanolamine N-methyltransferase (PNMT). In addition, there were cells with weak to moderate reactivity to TH and DBH but not to PNMT. Also totally negative cells were constantly seen. These findings were confirmed by using consecutive sections for the localization of different enzymes and by using the Tramu method to elute previous staining and by restaining the same sections with the other antibodies. It is concluded that the retroperitoneal paraganglia of newborn rat consist of many paraganglion-type cells containing noradrenaline, some of them containing also adrenaline, a few neuron-like cells with TH and DBH immunoreactivity, and cells containing no catecholamines.
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PMID:Pre- and postnatal development of rat retroperitoneal paraganglia. 288 7

The morphology, number and distribution of catecholaminergic neurons, as visualized either with the aluminum-catalysed formaldehyde method for catecholamines or with the immunohistochemical method for the catecholamine-synthesizing enzymes tyrosine hydroxylase and aromatic L-amino acid decarboxylase, respectively, were analysed within the rat dorsal hypothalamus, ventral thalamus and adjoining regions (A11 and A13 cell groups). Both polyclonal rabbit and monoclonal mouse tyrosine hydroxylase antibodies were used in elution-restaining and double-staining experiments, respectively. Some of the animals also received spinal injections of the fluorescent tracer True Blue in order to retrogradely label cells projecting to the spinal cord. With respect to the number and distribution of catecholaminergic neurons in the A11 and medial A13 cell groups, including the spinal-projecting subpopulation, the results obtained with the two methods were very similar, indicating that within these regions of the CNS the two methods in principle visualize identical cell populations. However, the catecholaminergic cells were distinctly larger and their processes appeared more extensive with the immunohistochemical method. Animals processed for immunohistochemistry exhibited a lower total number of retrogradely labelled cells in the A11 area than those analysed with aldehyde-induced fluorescence despite the fact that both methods revealed similar numbers of retrogradely labelled tyrosine hydroxylase-positive and catecholamine-containing cells, respectively. The reason for these discrepancies, which are probably of methodological nature, are discussed. While this study shows that the results obtained with the two methods within the A11 and medial A13 cell group are very similar and thus strengthens the earlier proposed concept of the organization of the diencephalospinal dopaminergic system, it also documents that in intermingling and nearby CNS regions there are cell bodies which cannot be demonstrated with the aldehyde fluorescence method, but which still contain tyrosine hydroxylase and/or aromatic L-amino acid decarboxylase-like immunoreactivity. One explanation is low levels of enzyme and/or dopamine combined with a comparatively low sensitivity of the histochemical method. Thus, neurons containing both enzymes are probably dopaminergic, even if catecholamine fluorescence cannot be demonstrated. Neurons containing tyrosine hydroxylase, but lacking both aldehyde induced fluorescence and aromatic L-amino acid decarboxylase, may also still be dopaminergic.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Studies on dopamine-, tyrosine hydroxylase- and aromatic L-amino acid decarboxylase-containing cells in the rat diencephalon: comparison between formaldehyde-induced histofluorescence and immunofluorescence. 289 14

Dopamine (DA) was early demonstrated in the arcuate nucleus by means of the formaldehyde-induced histofluorescence method. In the present study we have investigated the distribution of cell bodies in the arcuate nucleus with antisera against tyrosine hydroxylase (TH), aromatic L-amino acid decarboxylase (AADC) and DA. The results indicate that TH-immunoreactive cells in the dorsomedial part of the arcuate nucleus also contain immunoreactivity for both AADC and DA. However, TH-positive cells in the ventrolateral arcuate nucleus lacked AADC- and DA-immunoreactivity with the sensitivity of the present methods. The findings raise the question whether the ventrolateral cells synthesize L-DOPA or DA as endproducts.
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PMID:Do tyrosine hydroxylase-immunoreactive neurons in the ventrolateral arcuate nucleus produce dopamine or only L-dopa? 290 21

Expression of catecholaminergic characteristics by primary sensory neurons was examined in the vagal nodose and glossopharyngeal petrosal ganglia of the normal adult rat in vivo. Catecholaminergic phenotypic expression was documented by immunocytochemical localization of tyrosine hydroxylase (TyrOHase; EC 1.14.16.2), radiochemical assay of specific TyrOHase catalytic activity, and cytochemical localization of formaldehyde-induced catecholamine fluorescence (FIF) within principal ganglion cells. The TyrOHase-containing cells exhibited morphologic features typical of primary sensory neurons, such as an initial axon glomerulus and a single, bifurcating neurite process. These cells were distinguished from TyrOHase- and FIF-positive small intensely fluorescent cells by size, morphology, and staining intensity. TyrOHase-containing neurons appeared to be insensitive to neonatal treatment with 6-hydroxydopamine, thereby distinguishing them from sympathetic neurons. Nodose and petrosal ganglia of adult rats exhibited TyrOHase catalytic activity, linear with respect to tissue concentration over a 10-fold range, indicating that the immunoreactive enzyme was functional. Transection of specific ganglionic nerve roots depleted TyrOHase catalytic activity and neuronal immunoreactivity within the petrosal ganglion, suggesting that target organ innervation regulates enzyme levels within ganglion perikarya. Our study indicates that primary sensory neurons express catecholaminergic transmitter traits in the normal adult rat. Consequently, in the periphery, catecholaminergic characters are not restricted to the sympathoadrenal axis but are expressed by functionally and embryologically diverse populations of autonomic neurons.
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PMID:Expression of catecholaminergic characteristics by primary sensory neurons in the normal adult rat in vivo. 613 85


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