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 method of perfusion-fixation of the human brain is described and compared with immersion-fixation by immunoperoxidase staining for several substances (tyrosine hydroxylase, substance P, choline acetyltransferase, glutamate decarboxylase, Met-enkephalin, and neuron-specific enolase) in human striatum. Results from 1-cm slices fixed by immersion for 1, 2, 4 and 8 days were compared with results from slices of perfused brain postfixed for the same time periods. The fixative used in all steps was 4% paraformaldehyde at 4 degrees C. In the immersion-fixed brains, optimal immunoreaction for tyrosine hydroxylase and glutamate decarboxylase was limited to a depth of 1-2 mm from the surface of the brain slice. In contrast, staining density in perfusion-fixed brains was relatively homogeneous and of high quality. The other antigens studied displayed more uniform staining throughout the section with both perfused and immersed brains. Investigators intending to study human brain immunohistochemistry using immersion-fixation should be aware of the possibility of depth-related variations in staining intensity and would be wise to determine whether this effect is significant for the antigens they choose to study.
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PMID:Perfusion-fixation of the human brain for immunohistochemistry: comparison with immersion-fixation. 243 8

Dopamine (DA)-containing cells of the medial basal hypothalamus (MBH) were dissociated and maintained in culture for up to 9 days. Cultures were evaluated both biochemically and immunochemically for DA activity. DA biosynthesis was determined using incorporation of [3H]tyrosine and was analyzed by HPLC with electrochemical detection. Immunochemical studies were performed to identify tyrosine hydroxylase (TH)-positive and neuron-specific enolase (NSE)-positive cells. Morphometric analyses determined the cell size, density, process length and the percent of neurons which were catecholaminergic. TH-positive neurons ranged from 6 to 8% of the total neuronal population when examined over days 3-9 of culture and the length of TH-positive neurites was significantly greater than that of NSE-positive cells. There was incorporation of [3H]tyrosine into DA as evidenced by the presence of [3H]DA in both the media and tissue and the inhibition of synthesis with alpha-methyl-p-tyrosine. There was a greater amount of labeled DA in the media than in the tissue at every time point examined. On the other hand, biosynthesis of DA in fresh brain tissue revealed approximately equal levels of DA in the media and tissue. These studies indicate that DA continues to be synthesized in dissociated cultures of MBH as evidenced by both the biochemical and immunochemical analyses and that there appears to be some alteration in the ability of these neurons to store the newly synthesized amine.
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PMID:An immunochemical and biochemical study of catecholaminergic activity in dissociated hypothalamic cultures. 256 5

Flow cytometry has been revealed as a powerful technique for studying cell populations. The availability of the method to identify, analyze and isolate specific populations of central nervous system cells will be of great aid for studying the in vivo (i.e. neural transplants) and in vitro (i.e. cell cultures) behavior of these cells. The present report describes the analysis and cell sorting of a population of retrogradely fluorescence-labeled dopamine-containing neurons from ventral mesencephalon. Dopamine neurons were identified by immunohistochemical localization of neuron-specific enolase and tyrosine hydroxylase. After being maintained in culture, this relatively pure population differentiates toward a mature phenotype bearing a prominent neuropil.
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PMID:Selective flow cytometric sorting of viable dopamine neurons. 273 Oct 38

Embryonal carcinoma cells are useful in the study of embryogenesis and development, and their differentiation into neurons serves as a model of neuronal development. Retinoic acid was used to differentiate P19S18O1A1 embryonal carcinoma cells into neuronal, glial, and fibroblast-like cells and the phenotype of the neuronal population was examined. Neuron-specific enolase was present in the neuronal cells, suggesting that these neurons had reached some degree of maturity. A population (approximately 70%) of the neurons showed positive immunocytochemistry for tyrosine hydroxylase, dopamine beta-hydroxylase and phenylethanolamine N-methyltransferase, three enzymes in the pathway of catecholamine synthesis. Therefore a population of the neurons appeared to be adrenergic. These neurons also showed a low level of histofluorescence for endogenous catecholamines and exhibited an exogenous catecholamine reuptake system. In order to determine the phenotype of other neuron-like cells found to be negative for the adrenergic properties examined, immunocytochemistry for neuropeptides and neurotransmitters known to coexist within central neurons was performed. Serotonin, vasoactive intestinal peptide, glutamic acid decarboxylase, and choline acetyltransferase were all absent from retinoic acid-treated P19S18O1A1 neuronal cultures. These studies, along with those that compare the effects of retinoic acid and other growth modulators on neuronal differentiation of embryonal carcinoma cells, should aid in the understanding of neuronal induction and development in vivo.
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PMID:Characterization of neurotransmitter phenotype during neuronal differentiation of embryonal carcinoma cells. 289 47

The structural organization of the guinea-pig uterine innervation was investigated by an immunofluorescence method using neurofibrillary protein (NF) and neuron-specific enolase (NSE) as general neuronal markers. NF- and NSE-immunoreactive nerve trunks and non-varicose nerves formed continuous networks similar to nerves with analogue morphology and with immunoreactivities for tyrosine hydroxylase (TH; adrenergic nerves) and neuropeptide Y (NPY). NF- and NSE-immunoreactive non-varicose nerves occurred in the myometrium and along vessels, where TH- and NPY-immunoreactive varicose nerves were also comparatively frequent. After chemical sympathectomy all TH- and NPY-immunoreactive varicose nerves and most NF- and NSE-immunoreactive non-varicose nerves disappeared, suggesting colocalization of TH, NPY, NF and NSE immunoreactivities. During pregnancy all NF-, NSE-, TH- and NPY-immunoreactive nerve structures disappeared in the foetus-bearing uterine horns whereas in the cervix and non-foetus-bearing uterine horns only the myometrial TH- and NPY-immunoreactive varicose nerves disappeared. After parturition there was a complete structural restoration of all types of immunoreactive nerves in previously non-foetus-related tissue. The reinnervation of this tissue followed a similar time-course to that after chemical sympathectomy. In contrast, the reinnervation of previously foetus-related tissue was much slower and incomplete. In conclusion, the whole autonomic uterine innervation undergoes overt structural changes during pregnancy and these changes are related to the foetus-bearing regions.
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PMID:Organization of the guinea-pig uterine innervation. Distribution of immunoreactivities for different neuronal markers. Effects of chemical- and pregnancy-induced sympathectomy. 290 52

We have identified a new subline of PC12 pheochromocytoma cells (PC12D cells) in which neurites are extended within 24 hr in response to cAMP-enhancing reagents as well as in response to nerve growth factor (NGF), but not in response to epidermal growth factor or phorbol diester. Anti-NGF antiserum did not affect forskolin (FRK)-induced neuritic recruitment. FRK-induced neurites exhibited growth cones and contained secretion granules and many parallel arrays of microtubules as was the case with NGF-induced neurites. FRK, but not NGF, increased the levels of intracellular cAMP and activated adenylate cyclase in the membrane fraction. Both NGF and FRK enhanced the activities of tyrosine hydroxylase (TH), acetylcholinesterase (AchE), and ornithine decarboxylase (ODC), but not the levels of neuron-specific enolase. Enhanced levels of intracellular cAMP mimicked the effects of NGF on neuritic growth, TH, AchE, and ODC activities in PC12D cells, even though NGF does not act through elevation of levels of cAMP.
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PMID:Neuritic growth from a new subline of PC12 pheochromocytoma cells: cyclic AMP mimics the action of nerve growth factor. 303 56

The various subpopulations of autonomic and sensory nerves supplying the mammalian cardiovascular system may be demonstrated using specific immunocytochemical and histochemical techniques, but no single marker has previously been available for the visualisation of the entire innervation. Protein gene product (PGP) 9.5 was first identified in extracts of human brain and found to represent a major protein component of the neuronal cytoplasm. We have demonstrated that PGP 9.5 immunoreactivity occurs in the guinea pig cardiovascular innervation and is present in more individual nerve fibres than other general neuronal markers (neuron-specific enolase and neurofilaments). PGP 9.5 immunoreactivity was localized to both intrinsic neurones and nerve fibres in the guinea pig heart. In the vascular system PGP 9.5-immunoreactivity occurred in an extensive plexus of fine perivascular nerve fibres and fascicles running around and along both arteries and veins, mainly at the adventitial-medial border. At the ultrastructural level, this immunoreactive material was localized to the axonal cytoplasm and did not appear to be associated with cytoskeletal elements or secretory vesicles. 6-Hydroxydopamine (6-OHDA) pretreatment resulted in the degeneration of noradrenergic axon terminals containing PGP 9.5, tyrosine hydroxylase (TH) and neuropeptide tyrosine (NPY) immunoreactivities. Most of the perivascular nerve fibres which remained displayed substance P- and calcitonin gene-related peptide (CGRP) immunoreactivity, as well as PGP 9.5 immunoreactivity. Capsaicin pretreatment resulted in a depletion of both substance P and CGRP immunoreactivity, but had no apparent effect on PGP 9.5 immunostaining. In the heart PGP 9.5 immunoreactivity also appeared to be present in presumed postganglionic cholinergic nerves. PGP 9.5 may be a useful marker when examining regional variations in cardiovascular innervation and for determining the relative proportions of nerve subpopulations.
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PMID:The visualisation of cardiovascular innervation in the guinea pig using an antiserum to protein gene product 9.5 (PGP 9.5). 310 56

A case of esthesioneuroepithelioma was investigated ultrastructurally and immunohistochemically, using antibodies against neurofilament protein (NFP), glial fibrillary acidic protein (GFAP), keratin, neuron-specific enolase (NSE), S-100 protein (S-100), and tyrosine hydroxylase (TH). The tumor initially manifested as an epidural mass in the anterior cranial fossa in a 64-year-old man, and about 3 1/2 years later, autopsy further revealed extensive metastases to the lymph nodes of the neck and thoracic cavity. In the cranial and nasal cavities, the tumor was composed of fairly uniform, ill-defined cells arranged in nests which were surrounded by a fibrovascular stroma. These histological features were reproduced in the metastatic tumor nodules with frequent occurrence of tubular arrangements of the tumor cells. Ultrastructurally, two different cell types were well recognized by their characteristic morphological features, which were reminiscent of sensory neurons and sustentacular cells of the olfactory epithelium. No dense-cored secretory granules were observed in the tumor cells. Immunohistochemically, the tumor showed a variable number of cells positive for NFP, keratin, NSE and S-100. NFP was present in a relatively small number of cells, which were found diffusely in the nests. Keratin was observed in the cells mainly located at the periphery. NSE-positive cells tended to form irregular clusters in the center. A few S-100-positive cells were found, without any particular arrangement.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Esthesioneuroepithelioma: a tumor of true olfactory epithelium origin. An ultrastructural and immunohistochemical study. 343 22

The presence and distribution of different neural markers in 30 neuroblastic tumours (neuroblastomas, ganglioneuroblastomas) and 6 non-neuroblastic tumours were investigated by immunocytochemistry. Neuron-specific enolase (NSE), S-100 protein, tyrosine hydroxylase, neurofilaments and glial fibrillary acidic protein (GFAP) were localised in 3 undifferentiated neuroblastic tumours (group A), 12 poorly differentiated tumours (group B) and 15 well differentiated neuroblastic tumours (group C). Non-neuroblastic tumours (3 lymphomas and 3 Ewing sarcomas) showed no immunoreactivity. Tyrosine hydroxylase and, in particular, NSE were found in mature ganglion cells and developing neuroblasts of poorly and well differentiated tumours (groups B and C). S-100 was localised in neuroblasts with slender cytoplasmic processes in the same groups. Neurofilaments were detected in ganglion cells and differentiated neuroblasts (groups B and C) while GFAP was localised in immature neuroblasts of undifferentiated and poorly differentiated tumours (groups A and B). Thus, there are differences in the neural proteins found in neuroblastic tumours and a wide panel of antibodies against neural markers may be a useful tool in the histological assessment of nervous system neoplasms.
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PMID:Neuronal and glial markers in tumours of neuroblastic origin. 614 50

The aim of this study was to investigate the neurochemical coding of myenteric neurons in the guinea pig gastric corpus by using immunohistochemical methods. Antibodies and antisera against calbindin (CALB), calretinin (CALRET), choline acetyltransferase (ChAT), calcitonin gene-related peptide (CGRP), dopamine beta-hydroxylase (DBH), beta-endorphin (ENK), neuropeptide Y (NPY), neuron-specific enolase (NSE), nitric oxide synthase (NOS), protein gene product 9.5 (PGP), parvalbumin (PARV), serotonin (5-HT), somatostatin (SOM), substance P (SP), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP) were used. Double- and triple-labeling studies revealed colocalization of certain transmitters and enabled the identification of distinct subpopulations of gastric enteric neurons. NPY/VIP/NOS/ENK were present in 28% of all neurons, whereas 11% had NPY/VIP/DBH/ChAT; NOS-only neurons made up 2% of the population. The combination SP/ChAT/ENK occurred in 21% of the population, whereas SP/ChAT/ENK/CALRET and SP/CHAT/SOM/ +/- CALRET was identified in 5% and 6% of all cells, respectively. 5-HT-containing neurons comprised 2% of all cells and could be further classified by the presence of additional antigens as 5-HT/SP/(ChAT) or 5-HT/VIP/(ChAT). Approximately 21% of all neurons contained only ChAT with no additional antigen present and are referred to as ChAT/-. Gastric myenteric ganglion cells were not immunoreactive for CALB, PARV, CGRP, or TH. The results of this study indicate that gastric myenteric neurons can be characterized on the basis of different chemical coding. Neurochemical coding of corpus myenteric neurons revealed some similarities and significant differences in comparison with other regions of the gut. These differences might reflect adaptation of enteric nerves according to regional specialization and the distinct functions of the proximal stomach as a gastric reservoir.
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PMID:Neurochemical coding of enteric neurons in the guinea pig stomach. 753 52


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