Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P02794 (ferritin)
 17,525 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Neuronal antigens can be demonstrated histologically by numerous direct and indirect immunocytochemical techniques in which a specific antibody is identified by a marker compound such as fluorescein isothiocyanate, ferritin, or horseradish peroxidase. One of the more sensitive methods for the light and electron microscopic localizations of antigens in sections of tissue is the peroxidase-antiperoxidase (PAP) technique. The experimental procedures and the results obtained using this technique for the localization of the catecholamine synthesizing enzyme, tyrosine hydroxylase, are described. The cellular and ultrastructural localization of the enzyme is demonstrated in perikarya, processes, and terminals of catecholaminergic neurons in rat brain. The immunocytochemical localization of tyrosine hydroxylase is compared to the localization of two peptides, substance P and [Met5]-enkephalin, in the A2 region of the medulla. These studies suggest that a synaptic interaction exists between the catecholaminergic neurons and neurons showing positive immunoreactivity for the peptides. The limitations of the PAP immunocytochemical technique are also discussed in relation to the immunocytochemical localization of tyrosine hydroxylase and other antigens.
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PMID:Immunocytochemical localization of neuronal antigens: tyrosine hydroxylase, substance P, [Met5]-enkephalin. 3 6

The inflammatory neuropeptide substance P acted as a costimulant for macrophage CSF-1-induced clonal proliferation of murine marrow-derived two signal-dependent mononuclear phagocyte progenitors. Substance P had no effect on clonal proliferation by progenitors responding solely to CSF-1. Substance P fragment 2-11 had no costimulatory activity; however, SP fragment 1-4 retained the full activity of the parent undecapeptide. Fragment 1-4 (ARG-PRO-LYS-PRO), a peptide containing a PRO residue between two positive charges, is a tuftsin-like (THR-LYS-PRO-ARG) tetrapeptide, and tuftsin exerted an identical costimulatory effect. Substance P, SP:1-4, and tuftsin were optimally effective as costimulants at 10(-7) to 10(-6) M. (ALA1)-tuftsin, an inhibitory analog of tuftsin, was a potent negative regulator of two signal-dependent colony formation. (ALA1)-tuftsin at concentrations less than or equal to 10(-9) M exerted dose-dependent inhibition of the positive effects of optimal concentrations of all of the co-stimulants tested, including bacterial LPS. The inhibitory tetrapeptide was equivalent in activity to ferritin, an established inhibitor of two signal-dependent colony formation. The results indicated that SP may influence myelopoiesis in addition to its other inflammatory and immunopotentiating properties. In addition, a potentially valuable modulator of SP and LPS responses in this system, (ALA1)-tuftsin, was identified.
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PMID:Substance P augmentation of CSF-1-stimulated in vitro myelopoiesis. A two-signal progenitor restricted, tuftsin-like effect. 245 23

We have examined the effect of the trophic protein, nerve growth factor (NGF), on organotypic cultures of fetal rat striatum. Treatment of cultures with NGF for 10-11 days resulted in a 5- to 12-fold increase in the specific activity of the cholinergic enzyme choline acetyltransferase (CAT; EC 2.3.1.6). in a dose-dependent fashion. This effect was not elicited by insulin, ferritin, or cytochrome c, proteins similar in structure or physicochemical properties to NGF. The effect of NGF on CAT activity was specifically blocked by anti-NGF antiserum, whereas treatment with the antiserum alone did not have a significant effect on the enzyme. Immunocytochemical studies of the treated cultures, using a monoclonal antibody directed against CAT, revealed positively stained neurons exhibiting dendritic and axonal processes. NGF did not have an effect on total protein content of the striatal cultures, suggesting a highly specific effect. Moreover, levels of substance P, a peptide localized to other, noncholinergic neurons, were not altered by NGF. Substance P remained unchanged after treatment with NGF for 12 days, whereas CAT activity increased 12-fold in sister cultures. Although the mechanisms of action of NGF on striatal cholinergic interneurons remain to be determined, the marked, specific response of CAT suggests that this well-defined trophic protein may play a critical role in normal brain development.
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PMID:Nerve growth factor promotes cholinergic development in brain striatal cultures. 386 96

We sought to determine the effect of substance P salivary stimulation on both electrical charges and cellular permeability in the tight junctions of rat submandibular gland cells. Microperoxidase (1,900 daltons) was used as a tracer. It was administered by close-arterial infusion via the glandular arteries, and secretory routes of acinar cells in the gland were determined cytochemically. In the resting gland, microperoxidase reaction product filled the lateral intercellular spaces up to the tight junctions, but did not penetrate them. In the substance P-stimulated gland, microperoxidase reaction product was present within tight junctions and the lumen. Both distribution and mobility of anionic sites on the surface of the submandibular gland cells were studied utilizing multivalent ligand, ruthenium red and cationized ferritin as probes. In the resting gland, ruthenium red deposits were located uniformly in all areas of the basal membrane and intercellular spaces except for the tight junctional region of acinar and ductal cells. In substance P-stimulated gland, ruthenium red deposits were present in the tight junctional region and, to a lesser extent, in the intercellular spaces. Electrical charges of the tight junctions area of the lateral plasma membrane were studied using intraductal injection of cationized ferritin. In the resting gland, cationized ferritin probe was present in the intercellular spaces and was bound weakly in the tight junctional region. In the substance P-stimulated gland, cationized ferritin was firmly adherent to the tight junctional region.
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PMID:Distribution of anionic sites during increasing tight junctional permeability in the rat submandibular gland. 750 20