Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q07644 (polypeptide)
 72,197 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A method is described whereby commercially available radioimmunoassay-grade antibodies specific for the polypeptide hormones calcitonin, gastrin, glucagon, and somotastatin are used to detect these antigens on paraffin sections of routinely fixed tissue. The hormone antibodies are applied to deparaffinized tissue sections as the primary specific immune sera using the standard peroxidase technic. The use of these hormone antibodies to detect their respective antigens has proved valuable in demonstrating polypeptide forming tumor cells in pathologic specimens.
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PMID:The utilization of radioimmunoassay antibodies for the immunohistologic staining of polypeptide hormones on paraffin-embedded tissue. 8 76

Carcinoma of the bronchus can produce several polypeptide hormones and therefore has the capacity to cause most syndromes of endocrine hyperfunction. All pituitary hormones can be synthesized ectopically; furthermore, the production of hormones from the hypothalamus (CRF), the placenta (HCG, HPL) and the C-cells of the thyroid (calcitonin), as well as parathormone and prostaglandins has been described. The paraneoplastic syndrome may often be more dangerous for the patient than the tumor growth itself, and can lead to early death. On the other hand, it may allow the early detection of an unsuspected tumor. The ectopic hormones and other nonendocrine proteins and peptides can be used as tumor markers, and can demonstrate the effect of treatment and early recurrence or metastases. An ideal tumor marker should have the following characteristics: 1. production exclusively by neoplastic tissue, 2. direct correlation with tumor size, 3. substances common to all tumor types ("large spectrum tumor marker") although specific tumor markers for special tumors should be available, 4. the assays must be easy and automation should be possible. At present no tumor marker satisfies all these conditions. The measurement of several tumor markers and the use of discriminant analysis may extend their diagnostic value and open the way for biochemical detection of cancer in the future.
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PMID:[Ectopic hormone formation and tumor markers in bronchial neoplasms]. 22 36

By means of a statistical analysis of the occurrence of amino-acid residues in the polypeptide chains of several gastro-entero-pancreatic (GEP) hormones an investigation was undertaken to determine whether any of these hormones might be related to each other--possibly from an evolutionary point of view. Particular interest was paid to the occurrence of small charged segments, i.e. those with acidic or basic amino acid residues, since such segments can be presumed to play a role in hormonal receptor binding mechanisms. By this method hormonal relationships were suggested by the observation that these small charged amino-acid sequences, contained in the hormonal structures, match as a result of non-randomness. It was found that hagfish and human insulin were related on a molecular level not only to the newly discovered (avian, bovine, human) pancreatic polypeptide (PP) but also to some other GEP hormones (VIP, GIP, glucagon) as well as to calcitonin and to the alpha-subunit of the glycoprotein hormones. Interpretation of the statistical data suggests that all these peptide hormones are related by a common hexapeptide sequence which contributed, at an evolutionary point, to their molecular architecture. A hexapeptide segment of APP is statistically related to a sequence of equal size in the carboxy terminal region of the A-chain of both hagfish and human insulin, providing the first instance of their structural similarity. Correlations between PP, insulin, glucagon, VIP, and calcitonin provide a tentative basis for predicting the production of one or more of these peptide hormones by immature or de-differentiated cells of neoplasms and non-neoplastic pathologic lesions of the GEP endocrine system.
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PMID:Structural analysis of the molecular evolution of some gastro-entero-pancreatic hormones. 27 67

We have recently described the separation of a large number of polypeptide hormones, related peptides and some protein standards by hydrophobic interaction high-performance liquid chromatography (HPLC). This paper reports the practical application of these methods to the reproducible isolation and separation of components of a mixture of immunoreactive calcitonin-like proteins (less than 25 kD) synthesised and secreted by human tumour cells in vitro. Using hydrophobic interaction HPLC on ODS-silica for both preliminary bulk fractionation and subsequent analytical separation greater than 80% recoveries of small (ng) quantities of immunoreactive proteins were obtained from samples containing less than 100 mg total protein, and characteristic profiles of synthesised and secreted materials were established. Using a partially purified hypothalamic extract, containing a number of small proteins (12--25 kD), we have also examined the effects of varying chromatographic conditions in an attempt to modify the separations obtained with ODS-silica using an acid-saline-acetonitrile gradient elution system at ambient temperature, and achieve further resolution of its components. No useful selective effects were observed when temperature, organic modifier, gradient profile or hydrophobic stationary phase were altered. These techniques may not therefore be inherently capable of completely resolving all components of natural protein mixtures. They do, however, offer an adjunct to and in certain cases a substitute for conventional methods of protein separation.
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PMID:Use of hydrophobic interaction methods in the isolation of proteins from endocrine and paraendocrine tissues and cells by high-performance liquid chromatography. 54 29

Synthetic salmon calcitonin was administered subcutaneously to 12 inpatients with several primary psychotic diagnoses. Increases in serum total calcium and inorganic phosphorus levels and decreases in CSF calcium level had earlier been observed during periodic psychotic agitation or mania. By contrast, calcitonin, which decreased serum calcium and phosphorus levels and increased CSF calcium level, appeared to produce transient (24-hour) increases in depression and decreases in arousal in this double-blind placebo-controlled trial. Quantitative activity monitoring confirmed the rater's impression that this agent had tranquilizing or depressant effects in such patients. When given in the evening, this polypeptide also appeared to delay sleep onset, as demonstrated both by nurses' 30-minute sleep checks and by the same longitudinal activity record. A decreased hypocalcemic response to calcitonin was noted in the agitated patients, which might explain the increases in serum calcium level described at the "switch".
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PMID:Use of calcitonin in psychotic agitation or mania. 76 Jun 98

The C-cell is the source of the hypocalcemic polypeptide hormone, calcitonin. Sequential increments in calcitonin response to provocative calcium and pentagastrin infusions have been used to identify family members at high risk for the development of medullary thyroid carcinoma, a neoplasm of C-cell origin. Correlative light microscopic and immunohistochemical studies have permitted the identification of a spectrum of C-cell proliferative abnormalities ranging from C-cell hyperplasia (CCH) to invasive medullary thyroid carcinoma. Ultrastructurally, both normal and hyperplastic C-cells occupied an intrafolliculat localization, being separated from the interstitium by the follicular basal lamina and from the luminal colloid by extensions of the follicular cell cytoplasm. These relationships were maintained in areas of advanced hyperplasia where C-cells often completely encircled and displaced the follicular epithelium. Nodular CCH was characterized by the complete obliteration of the follicular space by C-cells. In these areas, prominent reduplications as well as occasional defects in the basal lamina were noted. Some of the solid C-cell nodules adjacent to areas of medullary thyroid carcinoma appeared to form by gradual replacement of follicles by C-cells and did not represent sites of intrathyroidal vascular or lymphatic extension. Two major cell types were noted in cases of CCH. One cell type which was filled with secretory granules measureing 280 nm. in diameter (type I) predominated in areas of diffuse CCH and was also found in control thyroid glands. The larger number of secretory granules in this cell type together with the relative lack of development of granular endoplasmic reticulum and Golgi regions suggested that these cells were in the storage phase of their secretory cycle. The second cell type had fewer secretory granules, which measured 130 nm. in diameter (type II), and was characteristically located in areas of nodular CCH. Type II granules were found in cells with cytologic evidence of active protein synthesis and secretion. Variations in granule morphology and cell ultrastructure may be correlated with functional variations in C-cell populations.
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PMID:C-cell hyperplasia. An ultrastructural analysis. 83 36

We have developed methods for the long-term maintenance of monolayer cultures of both human and trout calcitonin-secreting (C-) cells (Roos et al., 1974a, 1975). Secreted calcitonin (CT) can be measured by specific and sensitive radioimmunoassays for human calcitonin (HCT) and trout calcitonin (TCT) (Deftos, 1971; Deftos et al., 1974; Roos et al., 1974b). The combined application of these cell culture and radioimmunoassay methods to the in vitro study of CT secretion has revealed fundamental differences in the regulation by divalent ions of CT secretion in mammalian and nonmammalian C-cells. Our results also indicate a specific role for secretin as a CT secretagogue in trout. In addition to establishing the individual secretory effects of calcium and the enteric polypeptide hormones on the C-cells of both species, we have investigated the combined effects of these agents in both human and trout C-cell cultures. The noncompetitive augmentation of the secretory effects resulting from the actions of specific combinations of these secretagogues in each of these C-cell populations suggests that CT secretion is regulated by co-ordinate interaction of specific ionic and peptide secretagogues. An elucidation of the cellular mechanisms involved in such multifactorial control of C-cell function should result from the continued investigation of CT secretion in these C-cell cultures.
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PMID:Regulation of calcitonin secretion in vitro. 105 79

Hypocalcemia following gastrin administration occurs in thyroparathyroidectomized (TPTX) as well as thyroid intact rats. Hypophosphatemia does not accompany the hypocalcemia induced by gastrin. These data suggest that a mechanism other than release of calcitonin from the thyroid gland may be involved in this response in the rat. Neither adrenalectomy, nephrectomy, nor excision of the pancreas and small and large intestine altered the hypocalcemic response to gastrin. Gastrectomy, however, eliminated all hypocalcemia following administration of this polypeptide in both thyroid intact and TPTX rats. Removal of the antrum of the stomach did not influence the hypocalcemic response to gastrin. Resection of the proximal 75% of the stomach, however, inhibited the hypocalcemic response to gastrin as did total gastrectomy. Thus, in the rat, the proximal stomach appears to play an important role in mediating this response.
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PMID:The importance of the stomach in gastrin-induced hypocalcemia in the rat. 112 84

We have studied the effects of several porcine enteric polypeptide hormones on trout calcitonin (tCT) secretion in long-lived monolayer cultures of calcitonin-secreting (C-) cells derived from trout ultimobranchial glands. Gastrin, pancreozymin (CCK-PZ), glucagon, and secretin have dose-related stimulatory effects on tCT secretion; the distinct effects of secretin on tCT secretion are in contrast to its lack of CT secretagogue activity in some mammals. Synthetic peptide hormones and/or their structural analogs have variable secretory effects which correspond in general to the potency of the analogs for the well-recognized biological actions of these various peptide hormones in mammals. Although enteric peptide hormones are present in fish, their physiological role in the regulation of CT secretion has not been studied. These in vitro studies indicate a possible role for these hormones in the control of tCT secretion and support the concept that there are differences in the regulators of C-cell function in higher and lower vertebrates. In vitro studies of fish CT secretion are needed to establish the physiological significance of these in vitro studies of fish C-cell function.
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PMID:Calcitonin secretion in vitro. II. Regulatory effects of enteric mammalian polypeptide hormones on trout C-cell cultures. 126 21

Recently, we have demonstrated that guinea-pig epicardial coronary arteries are supplied by numerous nerve fibres containing neuropeptide Y (NPY) immunoreactivity. However, examination of vasomotor responses revealed that NPY did not elicit a contractile response in these arteries. In contrast, acetylcholine (ACh), calcitonin gene-related peptide (CGRP), substance P and vasoactive intestinal polypeptide (VIP) all relaxed precontracted arteries. In the present study, we have used histochemical, immunohistochemical and in vitro pharmacological techniques, in order to further investigate the possible role of NPY in guinea-pig epicardial coronary arteries. A double-immunofluorescence staining technique revealed that CGRP and substance P were co-localized in nerve fibres distinct from those displaying NPY immunoreactivity. Furthermore, using a method combining immunofluorescence and histochemical techniques, we observed that putative cholinergic nerve fibres (identified by their acetylcholinesterase content) and NPY-immunoreactive nerve fibres are two different nerve populations. An in vitro pharmacological method demonstrated that NPY markedly inhibited the relaxant responses mediated by ACh, VIP, substance P and isoprenaline but had no effect on CGRP. These results suggest that NPY-containing nerves associated with guinea-pig epicardial coronary arteries may be predominantly involved in modulating the action of vasodilator agents.
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PMID:Neuropeptide Y modulates the action of vasodilator agents in guinea-pig epicardial coronary arteries. 127 55


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