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

The identity of the neuronal nicotinic alpha-bungarotoxin (alpha-BGT) site, which appears to be distinct from the functional nicotinic receptor, is unclear. Recent work in our laboratory has shown that the thymus-derived polypeptide thymopoietin potently and specifically interacts at the nicotinic alpha-BGT site in brain. The present results show that thymopoietin also interferes with the binding of 125I-alpha-BGT to chromaffin cells in culture; a dose-dependent inhibition in binding was observed, with an IC50 of 10(-8) M. To assess the long term effect(s) of thymopoietin in nervous tissue, chromaffin cells were exposed to the polypeptide for varying periods of time. Incubation of the cells in culture with thymopoietin (10(-9) to 3 x 10(-7) M) for 2 to 7 days resulted in an approximate 3-fold increase in alpha-BGT binding. Saturation analysis indicated this was due to an increase in the Bmax. The thymopoietin-induced increase in binding could be reversed with nicotine: thus, the sites can be regulated by a nicotinic receptor ligand. Although thymopoietin potently interacted at the nicotinic alpha-BGT receptor, nicotinic receptor responsiveness was not affected after short or long term exposure to the peptide. Neither basal nor nicotinic receptor-stimulated tyrosine hydroxylase activity was altered by thymopoietin. As well, resting and acetylcholine-evoked noradrenaline release remained similar to control after exposure of the cells to the polypeptide. These results indicate that the thymic polypeptide thymopoietin specifically interacts with the nicotinic alpha-BGT receptor population and, furthermore, can regulate the toxin binding sites in chromaffin cells in culture.
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PMID:Thymopoietin, a thymic polypeptide, regulates nicotinic alpha-bungarotoxin sites in chromaffin cells in culture. 837 21

Bovine adrenal tyrosine hydroxylase (TH) is isolated in a partially inhibited state with the feed-back inhibitors adrenaline and noradrenaline tightly coordinated to high-spin (S = 5/2) Fe(III) at the active site. In addition to the charge-transfer interaction with iron, an additional charged group in the polypeptide chain, with an apparent pKa of about 5.3 at 4 degrees C, is involved in the binding of catecholamines. Protonation of this group increases the pseudo-first order rate constant for the dissociation of the TH-[3H]noradrenaline complex more than 100-fold at 4 degrees C. At pH 7.0 and 30 degrees C, phosphorylation of Ser-40 causes a 6-fold increase in the rate constant for this dissociation.
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PMID:pH-dependent release of catecholamines from tyrosine hydroxylase and the effect of phosphorylation of Ser-40. 197 Jul 88

The distribution and morphology of neurons containing the dopamine- and cyclic AMP-regulated phosphoprotein, DARPP-32, were investigated in the bed nucleus of the stria terminalis (BST) and the central nucleus of the amygdala (CeA). DARPP-32 immunoreactive neurons are numerous in both regions, but are restricted to the lateral dorsal and the lateral juxtacapsular subdivisions of the BST, and the central lateral and lateral capsular subdivisions of the CeA. Immunoreactive neurons in the lateral dorsal BST, and the central lateral and lateral capsular CeA are similar morphologically, while those in the juxtacapsular BST appear to be a subpopulation of striatal medium-sized spiny neurons. The distribution of DARPP-32 immunoreactive neurons in the BST and CeA overlaps considerably with axonal plexuses containing tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP), and calcitonin gene-related peptide (CGRP). These studies provide further evidence of the close relationship between the CeA and BST, and also provide anatomical evidence for possible interactions between neurotransmitters, neuropeptides, and phosphoproteins.
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PMID:Localization of DARPP-32 immunoreactive neurons in the bed nucleus of the stria terminalis and central nucleus of the amygdala: co-distribution with axons containing tyrosine hydroxylase, vasoactive intestinal polypeptide, and calcitonin gene-related peptide. 197 Dec 24

Respiratory tract nerves have cell bodies outside (sensory, sympathetic) and inside (parasympathetic) the organ and contain bioactive peptides. These include calcitonin gene-related peptide and tachykinins (sensory nerves), vasoactive intestinal polypeptide (parasympathetic nerves), and neuropeptide with tyrosine (sympathetic nerves). Because transplantation interrupts the extrinsic nerve supply to the tissues, we have examined transplanted human respiratory tracts (n = 11) removed at retransplantation 2 to 42 months after the primary transplant in order to determine whether any nerves and peptide synthesis persist. As controls to establish nerve distribution in human respiratory tract, tissues were obtained from 10 lung resections and five autopsies. Cryostat sections were immunostained to demonstrate the general neural marker PGP 9.5, neuropeptides, and the catecholamine-synthesizing enzyme tyrosine hydroxylase. Nerves immunoreactive for PGP 9.5 were detected in all transplanted tissues. They were fewer in number overall than in control tissue, significantly so in epithelium of trachea and bronchus where they were present sparsely in only three cases. Nerves immunoreactive for tyrosine hydroxylase were significantly fewer in the transplants. Peptide-immunoreactive nerves were also reduced in number in the transplants, except for vasoactive intestinal polypeptide, which was only significantly changed in blood vessels in the lung. Ganglion cells immunoreactive for tyrosine hydroxylase and neuropeptide with tyrosine were seen in the transplanted tissues in five cases, but never in the control tissues. We conclude that whereas some nerves and neuropeptide synthesis persist after extrinsic pulmonary denervation, potentially significant changes also occur, including the appearance in intrinsic parasympathetic neurones of immunoreactivity for a catecholamine-synthesizing enzyme and a peptide normally found in sympathetic nerves.
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PMID:Persistence of intrinsic neurones and possible phenotypic changes after extrinsic denervation of human respiratory tract by heart-lung transplantation. 197 6

We performed immunohistochemical analysis of specimens from three autopsied patients with Parkinson's disease, using antibodies to tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP), somatostatin, met-enkephalin, leu-enkephalin and substance P in an attempt to reveal the types of neurons that contain Lewy bodies (LBs) in the paravertebral and celiac sympathetic ganglia and in the enteric nervous system of the alimentary tract. In the sympathetic ganglia, almost all LB-containing neuronal cell bodies and processes were immunoreactive for TH. In the alimentary tract, however, most LBs were found in the VIP-immunoreactive (VIP-IR) neuronal cell bodies and processes. In spite of the significant presence of TH-IR neuronal cell bodies and processes in the alimentary tract, LB-containing TH-IR neuronal elements were rarely encountered. These findings indicate that in the alimentary tract, the VIP neuron system is mainly involved in the disease process of Parkinson's disease.
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PMID:Parkinson's disease: an immunohistochemical study of Lewy body-containing neurons in the enteric nervous system. 197 53

This immunohistochemical study of nerves in the synovial tissue of Sprague-Dawley rats demonstrated the occurrence of 4 neuropeptides and 2 enzymes that are involved in the synthesis of catecholamines. Substance P and calcitonin gene-related peptide were colocalized in fibers that terminated as varicosal endings in the synoviocyte layer. Similarly, tyrosine hydroxylase and dopamine beta-hydroxylase, which reflect the presence of noradrenaline, were colocalized with neuropeptide Y. These fibers were predominantly found adjacent to and within blood vessel walls. Immunoreactivity to vasoactive intestinal polypeptide was seen in varicose nerve terminals in the synoviocyte layer. Many were localized in vessel walls. There is accumulating evidence of an involvement of substance P and noradrenaline in the pathogenesis of inflammatory joint disease and nociception. The role of these colocalized neuropeptides, namely, calcitonin gene-related peptide and neuropeptide Y, in the pathophysiology of such conditions warrants further analysis.
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PMID:Noradrenergic and peptidergic nerves in the synovial membrane of the Sprague-Dawley rat. 197 38

Bronchial reactivity changes during childhood, indicating possible changes in neural control. Nerves supplying the intrapulmonary airways were therefore studied in autopsy tissue from 14 normal infants (0 to 3.5 yr), 3 children (8.3 to 10.75 yr), and 4 adults (17 to 24 yr). An indirect immunofluorescence technique was used to study the distribution and relative number of nerve fibers containing the general neuronal markers protein gene product 9.5 and synaptophysin. Nerve subpopulations were identified using antisera to neuropeptide tyrosine, vasoactive intestine polypeptide, somatostatin, substance P, calcitonin gene-related peptide, and the enzyme tyrosine hydroxylase. Between birth and 3 yr, the distribution and relative number of immunoreactive nerves shown by both the general neuronal markers and specific antisera did not change. Neuropeptide tyrosine-immunoreactive nerves were the most common peptide-containing nerve subpopulation identified in the human lung, supplying bronchial smooth muscle, submucosal glands, cartilage, and submucosa. Other peptide-containing nerves exhibited distinct distribution patterns. Two differences in the airway innervation were identified between cases aged 0 to 3.5 yr and the older age groups. Relatively fewer peptide-containing nerves occurred in the adult bronchioli and respiratory unit, but the relative number of vasoactive intestinal polypeptide-containing nerves supplying the bronchial and bronchiolar smooth muscle was greater in the two older age groups. Given these apparent age-related differences in the number of peptide-containing nerves supplying the human airway, studies on the development of peptide receptors are indicated.
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PMID:Immunohistochemical localization of peptide-containing nerves in human airways: age-related changes. 197 91

Previous work has demonstrated that a reconstituted basement membrane (RBM)-like matrix stimulates the development of catecholamine (CA)-containing cells in neural crest cultures. In the present work, we found that the proportion of tyrosine hydroxylase and somatostatin immunoreactive cells was increased substantially by an overlay of the RBM matrix. In contrast, there was little or no stimulation of the development of cells possessing several other phenotypic markers including A2B5, E/C8, vasoactive intestinal polypeptide, and the low and middle molecular weight avian neurofilament proteins. These results demonstrate that the response of neural crest cells to the RBM matrix is specific to a small set of phenotypes. In addition, we demonstrate that the phenotype of the adrenergic cells which develop in the presence of the RBM gel overlay is very similar, if not identical, to that of the adrenergic cells which differentiate in the absence of the RBM gel.
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PMID:The phenotypic response of cultured quail trunk neural crest cells to a reconstituted basement membrane-like matrix is specific. 197 42

The presence of tyrosine hydroxylase (TH) and vasoactive intestinal polypeptide (VIP) in the nerve fibers of the human palatine tonsil and paratonsillar secretory glands is reported. By immunohistochemistry TH-immunoreactive nerves and those immunoreactive to VIP were localized to the tonsil, in particular, the tonsillar vessel wall, extranodular lymphoid tissue and lymph nodule, and to the acinar basal surface of the paratonsillar glands. In the lymph nodule, immunoreactive varicose nerve profiles were observed inside the marginal zone. The germinal center was devoid of immunoreactive fibers.
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PMID:Immunolocalization of tyrosine hydroxylase and vasoactive intestinal polypeptide in nerve fibers innervating human palatine tonsil and paratonsillar glands. 197 67

The avian wulst, a laminated "bulge" in the dorsal telencephalon, contains several distinct regions. The posterolateral portion (visual wulst) has been proposed to be an avian equivalent of the mammalian striate cortex. The present study examines specific neurotransmitters and neuropeptides within the visual wulst by immunohistochemical techniques. Antisera and monoclonal antibodies against choline acetyltransferase (ChAT), nicotinic acetylcholine receptor (nAChR), tyrosine hydroxylase (TH), serotonin (5-HT), glutamic acid decarboxylase (GAD), gamma-aminobutyric acid A receptor (GABAAR), cholecystokinin (CCK), substance P (SP), leucine-enkephalin (L-ENK), neurotensin (NT), neuropeptide Y (NPY), somatostatin (SRIF), corticotropin-releasing factor (CRF), and vasoactive intestinal polypeptide (VIP) were used. Somata and neuropil displaying specific immunoreactivity were generally distributed in accordance with the laminar cytoarchitectonic organization of the wulst. The superficial layer of the wulst, the hyperstriatum accessorium, contained the highest densities of TH-, 5-HT-, SP-, NPY-, SRIF-, CRF-, and VIP-positive neuropil in the wulst, whereas the highest density of CCK- and NT-staining was found in the deepest layer of the wulst, the hyperstriatum dorsale. In addition to the traditionally defined four laminae of the wulst, the immunoreactive staining revealed several subregions within each lamina. The most dorsolateral portion of the wulst contained the highest densities of ChAT- and L-ENK-stained fibers in the wulst, as well as moderately dense staining of neuropil for 5-HT-, TH-, SP-, and CCK-like immunoreactivity. The nAChR-immunoreactivity was faint and distributed rather uniformly throughout the wulst. The results suggest that the wulst consists of multiple regional variations within layers comparable to laminar variations found within different cytoarchitectonic areas of the mammalian neocortex.
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PMID:Immunohistochemical analysis of the visual wulst of the pigeon (Columba livia). 197 83


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