76
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Ambler L, Bennett HP, Hudson AM, McMartin C. Fate of human corticotrophin immediately after intravenous administration to the rat. J Endocrinol 1982; 93:287-92. [PMID: 6283006 DOI: 10.1677/joe.0.0930287] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The distribution and degradation of tritium-labelled human 1-39 corticotrophin have been studied after intravenous administration to the rat. Within 5 min of injection of single major metabolite, 3-39 corticotrophin, appears in the circulation. This metabolite, however, has only 3.6% of the steroidogenic potency of 1-39 corticotrophin and the evidence suggests that it is formed in muscle and skin. By 5 min, extensive degradation had occurred in all the major tissues in the body (muscle, skin, liver, kidney, gut).
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77
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Browne CA, Bennett HP, Solomon S. Isolation and characterization of corticotropin- and melanotropin-related peptides from the neurointermediary lobe of the rat pituitary by reversed-phase liquid chromatography. Biochemistry 1981; 20:4538-46. [PMID: 6271168 DOI: 10.1021/bi00519a005] [Citation(s) in RCA: 69] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
A novel procedure utilizing reversed-phase high-performance liquid chromatography for the extraction and purification of peptides from biological tissues has been applied to the isolation of corticotropin-like intermediary lobe peptide (CLIP) and alpha-melanocyte-stimulating hormone (alpha-MSH) from the neurointermediary lobe of the rat pituitary. The isolation and characterization of two major forms of CLIP and two major forms of alpha-MSH are described. The isolated peptides have been identified by using enzymatic digestions and peptide mapping. The main form of ClIP is a peptide which has been modified by phosphorylation of the serine residue at position 31. This is the first peptide of endocrine origin reported to be modified in such a manner. A non-phosphorylated form of CLIP was also present at lower concentrations. The main form of alpha-MSH was found to be N,-O-diacetyl-alpha-MSH, with the more familiar mono-N-acetyl-alpha-MSH present to a much smaller extent. Thus, in the rat neurointermediary lobe, the two main corticotropin-related peptides present are mostly in modified forms which are the result of posttranslational modifications. It is only by the use of methodology such as that described in this paper that small alterations in peptide structure may be identified.
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78
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Bennett HP, Browne CA, Solomon S. Purification of the two major forms of rat pituitary corticotropin using only reversed-phase liquid chromatography. Biochemistry 1981; 20:4530-8. [PMID: 6271167 DOI: 10.1021/bi00519a004] [Citation(s) in RCA: 202] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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79
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Bennett HP, Solomon S, Goltzman D. Isolation and analysis of human parathyrin in parathyroid tissue and plasma. Use of reversed-phase liquid chromatography. Biochem J 1981; 197:391-400. [PMID: 7325962 PMCID: PMC1163138 DOI: 10.1042/bj1970391] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Reversed-phase liquid chromatography techniques have been used to extract and purify human parathyrin from parathyroid adenomas and to analyse the circulating forms of human parathyrin in plasma. Both the supernatant from tissue homogenates, and plasma were extracted with octadecylsilyl-silica (ODS-silica) in a batch procedure. Extracts were subjected to reversed-phase high-pressure liquid chromatography (h.p.l.c.) employing solvent systems composed of aqueous acetonitrile containing trifluoroacetic acid or heptafluorobutyric acid as hydrophobic ion-pairing reagents. The volatile solvents facilitated the radioimmunoassay, bioassay in vitro and amino acid analysis of column fractions and permitted monitoring for u.v. absorbance at 210nm. Isolated glandular parathyrin was found to be homogeneous by sodium dodecyl sulphate/urea/polyacrylamide-gel electrophoresis, to have an amino acid composition conforming to that of human parathyrin-(1--84)-tetraoctacontapeptide and to be bioactive in both renal adenylate cyclase and cytochemical bioassays. ODS-silica extraction permitted examination of large plasms samples by reversed-phase h.p.l.c., facilitating the resolution of the various circulating molecular forms of parathyrin according to their hydrophobic character. Because of its rapidity, excellent recovery and high resolving power, the methodology utilized is uniquely suited to the purification and analysis of parathyrin in tissues and body fluids.
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80
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Bennett HP, Browne CA, Solomon S. Biosynthesis of phosphorylated forms of corticotropin-related peptides. Proc Natl Acad Sci U S A 1981; 78:4713-7. [PMID: 6272271 PMCID: PMC320233 DOI: 10.1073/pnas.78.8.4713] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Phosphorylated forms of corticotropin[ACTH (1-39)], corticotropin-like intermediary lobe peptide[CLIP, ACTH (18-39)], and the common precursor for ACTH and beta-lipotropin (beta-LPH) have been identified in extracts of rat pituitaries, 32P-Labeled inorganic phosphate was successfully incorporated into ACTH (1-39), CLIP, and the ACTH/beta-LPH precursor in rat neurointermediary lobe explants and into ACTH (1-39) in isolated rat anterior pituitary cells. After peptidase digestion of the labeled CLIP and ACTH, the radioactive phosphate was recoverable as O-phosphoserine. The serine residue at position 31 was the only amino acid found to be phosphorylated in CLIP and ACTH (1-39). The unphosphorylated forms of both peptides were also synthesized. The demonstration of he incorporation of [32P]phosphate into CLIP, ACTH (1-39), and the ACTH/beta-LPH precursor is consistent with the hypothesis that, within the rat intermediary lobe, phosphorylated CLIP is derived from a phosphorylated form of the common precursor, with phosphorylated ACTH (1-39) acting as a biosynthetic intermediate.
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81
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Browne CA, Bennett HP, Solomon S. The isolation of characterization of gamma 3-melanotropin from the neurointermediary lobe of the rat pituitary. Biochem Biophys Res Commun 1981; 100:336-43. [PMID: 7259753 DOI: 10.1016/s0006-291x(81)80101-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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82
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Brubaker PL, Bennett HP, Baird AC, Solomon S. Isolation of ACTH1-39,ACTH1-38 and CLIP from the calf anterior pituitary. Biochem Biophys Res Commun 1980; 96:1441-8. [PMID: 6254534 DOI: 10.1016/0006-291x(80)90112-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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83
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van der Rest M, Bennett HP, Solomon S, Glorieux FH. Separation of collagen cyanogen bromide-derived peptides by reversed-phase high-performance liquid chromatography. Biochem J 1980; 191:253-6. [PMID: 7470094 PMCID: PMC1162205 DOI: 10.1042/bj1910253] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A new technique for separation of the CNBr cleavage products of collagen is described. It involves the use of a 30 nm pore reversed-phase high-performance liquid chromatography column eluted with a linear gradient of acetonitrile/water containing 0.01 M-heptafluorobutyric acid. The separation of type I, type II and type III CNBr peptides is described. Resolution is particularly good for the low-molecular-weight peptides. The method is fast, quantitative and sensitive, and the complete volatility of the eluent facilitates the recovery of the separated peptides.
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84
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Congote LF, Bennett HP, Solomon S. Rapid separation of the alpha, beta, G gamma and A gamma globin chains by reversed-phase high pressure liquid chromatography. Biochem Biophys Res Commun 1979; 89:851-8. [PMID: 486202 DOI: 10.1016/0006-291x(79)91856-4] [Citation(s) in RCA: 53] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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85
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Bennett HP, McMartin C. Distribution and degradation of two tritium-labelled corticotrophin analogues in the rat. J Endocrinol 1979; 82:33-42. [PMID: 225403 DOI: 10.1677/joe.0.0820033] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The distribution and degradation of corticotrophin-(1--24)-tetracosapeptide specifically labelled with tritium at Tyr2, Phe7 or Tyr23 and [D-Ser1, Lys17, Lys18]-corticotrophin-(1--18)-octadecapeptide amide labelled at Tyr2 were studied at various times after intravenous injection into rats. By characterizing the radioactivity in plasma and various tissues, an overall picture of the metabolic handling of the two peptides emerged. The peptides left the circulation rapidly, entering mainly muscle and skin where they were extensively degraded. The D-Ser1-containing analogue was less rapidly degraded and intact peptide persisted in muscle and skin for up to 1 h. This peptide probably returned to the circulation giving rise to the sustained plasma levels observed after injection of the D-Ser1-substituted octadecapeptide but not after injection of the tetracosapeptide. Although initially the kidneys did not clear such large amounts of peptide as did muscle and skin they played an important role by continuously and, on the basis of existing evidence, irreversibly clearing the peptides and peptide fragments from the circulation and degrading them.
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86
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Hudson AM, Ambler L, Bennett HP, McMartin C. Metabolism of tritiated corticotrophin in the rat [proceedings]. J Endocrinol 1979; 81:129P. [PMID: 222867] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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87
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Bennett HP, Hudson AM, Kelly L, McMartin C, Purdon GE. A rapid method, using octadecasilyl-silica, for the extraction of certain peptides from tissues. Biochem J 1978; 175:1139-41. [PMID: 233923 PMCID: PMC1186178 DOI: 10.1042/bj1751139] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Peptides can be recovered from tissues by homogenization in a carefully selected extraction medium followed by adsorption from the supernatant on a small bed of octadecasilyl-silica. Recoveries of corticotropins and somatostatin added to a variety of tissues were quantitative, and the peptides undamaged as determined by high-pressure liquid chromatography.
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88
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Bennett HP, McMartin C. Peptide hormones and their analogues: distribution, clearance from the circulation, and inactivation in vivo. Pharmacol Rev 1978; 30:247-92. [PMID: 228321] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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89
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Bennett HP, Hudson AM, McMartin C, Purdon GE. Use of octadecasilyl-silica for the extraction and purification of peptides in biological samples. Application to the identification of circulating metabolites of corticotropin-(1-24)-tetracosapeptide and somatostatin in vivo. Biochem J 1977; 168:9-13. [PMID: 202257 PMCID: PMC1184111 DOI: 10.1042/bj1680009] [Citation(s) in RCA: 160] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Peptides can be adsorbed on octadecasilyl-silica from large volumes of aqueous solution and eluted with aqueous solvent mixtures containing methanol or acetonitrile. These properties may be used for the extraction and purification of peptide fragments in plasma samples collected from rats. After intravenous injection of Synacthen [corticotropin-(1-24)-tetracosapeptide], it was shown that within 2 min the main circulating products were intact peptide and its sulphoxide. In addition, a number of fragments indicative of cleavage at the N- and C-termini were present. Most of the products formed from Synacthen have low biological activity. Somatostatin was rapidly cleaved in vivo and in vitro to a single product, which probably retains biological activity. The absence of other circulating products suggests that somatostatin is only inactivated once it leaves the circulation.
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90
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Baker JR, Bennett HP, Christian RA, McMartin C. Renal uptake and metabolism of adrenocorticotrophin analogues in the rat: an autoradiographic study. J Endocrinol 1977; 74:23-35. [PMID: 194997 DOI: 10.1677/joe.0.0740023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Renal resorption of tritiated adrenocorticotrophin analogues was studied in the rat using light microscopic and quantitative electron microscopic autoradiography. The synthetic corticotrophins used were Synacthen (corticotrophin-(1-24)-tetracosapeptide) and C41795-Ba ([D-Ser1,Lys17,Lys18]-corticotrophin-(1-18)-octadecapeptide amide), the tetracosapeptide being tritiated in either the tyrosine residue of position 2 or 23 or the phenylalanine of position 7 and the octadecapeptide in the tyrosine of position 2. Inspection of autoradiographs showed that peptides injected intravenously were resorbed into proximal tubules by endocytosis to produce vesicles whose radiolabel later appeared in lysosomes, a route previously elucidated for other peptides and proteins. The use of two techniques for analysis of electron microscopic autoradiographs, however, suggested that apical tubules also acquire label and are in some way involved in the transfer of resorbed labelled material from endocytotic vesicles to lysosomes. In addition, the autoradiographic analyses revealed that the duration of lysosomal labelling depends upon the position of tritium in the chain. Thus, when the CO2H-terminus of Synacthen was labelled, silver grains were more transiently associated with lysosomes than was the case when the NH2-terminal or core regions were tritiated, indicating a greater resistance of these portions of the peptide to attack by intracellular peptidase. The label from the chemically protected C 41795-Ba was also less readily expelled from the lysosomes of the proximal tubules.
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91
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Baker JR, Bennett HP, Hudson AM, McMartin C, Purdon GE. On the metabolism of two adrenocorticotrophin analogues. Clin Endocrinol (Oxf) 1976; 5 Suppl:61S-72S. [PMID: 212234 DOI: 10.1111/j.1365-2265.1976.tb03816.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The metabolism of Synacthen (corticotrophin-(1--24)-tetracosapeptide) and C-41795-Ba ([D-Ser1,Lys17,Lys18]-corticotrophin-(1--18)-octadecapeptide amide) have been compared in the rat following intravenous injection. Using Synacthen and C-41795-Ba labelled with tritium it was possible to follow the tissue distribution of the two peptides. The kidney was shown to concentrate intact peptide and fragments of both peptides. Autoradiography of perfused kidney sections demonstrated the uptake of radioactivity into the lysosomes of the kidney proximal tubule cells. Comparison of the distribution of radioactive products formed from the tetracosapeptide labelled in different positions indicates that, prior to renal uptake, metabolism is taking place at other sites in the body. It is suggested that rapid cleavage occurs extracellularly at or near the N- and C-termini. Then large fragments remaining in the circulation, together with any intact material, are filtered through the glomerulus and are taken up by endocytosis into the proximal tubule cells of the kidney. The synthetic N- and C-terminal protection of the octadecapeptide appears to inhibit the extracellular attack and so the concentration of intact peptide in the kidneys is initially higher than the tetracosapeptide. Although concentrations of radioactivity in other tissues are low in comparison with the kidneys, the quantities are quite high when the weight of the tissues are considered. Chromatographic analysis of this radioactivity reveals that the octadecapeptide gives rise to much higher tissue levels of intact peptide and we believe that this acts as a depot and gives rise to the sustained blood concentrations and prolonged biological effects observed with this peptide.
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92
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Lowry PJ, Bennett HP, McMartin C. The isolation and amino acid sequence of an adrenocorticotrophin from the pars distalis and a corticotrophin-like intermediate-lobe peptide from the neurointermediate lobe of the pituitary of the dogfish Squalus acanthias. Biochem J 1974; 141:427-37. [PMID: 4375977 PMCID: PMC1168096 DOI: 10.1042/bj1410427] [Citation(s) in RCA: 68] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
An adrenocorticotrophic hormone (ACTH) was isolated from extracts of the pars distalis of the pituitary of the dogfish Squalus acanthias by gel filtration and ion-exchange chromatography. It had 15% of the potency of human ACTH in promoting cortico-steroidogenesis in isolated rat adrenal cells. Sequence analysis revealed it to be a nonatria-contapeptide with the following primary structure: Ser-Tyr-Ser-Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Met-Gly-Arg-Lys-Arg-Arg-Pro-Ile-Lys-Val-Tyr-Pro-Asn-Ser-Phe-Glu-Asp-Glu-Ser-Val-Glu-Asn-Met-Gly-Pro-Glu-Leu. The N-terminal tridecapeptide sequence was identical with the proposed structure of dogfish alpha-melanocyte-stimulating hormone (alpha-MSH). On comparison with human ACTH eleven amino acid differences were seen, nine of which are in the 20-39 region of the molecule which is not essential for the steroidogenic activity of ACTH. A peptide identical with the 18-39 portion of this new ACTH was similarly isolated from the neurointermediate lobe of the pituitary where considerable amounts of dogfish alpha-MSH were found. This supported our view that ACTH as well as having a distinct biological role of its own is also the precursor of alpha-MSH.
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93
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Bennett HP, Lowry PJ, McMartin C. Structural studies of alpha-melanocyte-stimulating hormone and a novel beta-melanocyte-stimulating hormone from the neurointermediate lobe of the pituitary of the dogfish Squalus acanthias. Biochem J 1974; 141:439-44. [PMID: 4375978 PMCID: PMC1168097 DOI: 10.1042/bj1410439] [Citation(s) in RCA: 61] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
A melanocyte-stimulating hormone (MSH) has been isolated from extracts of the neurointermediate lobe of the pituitary of the dogfish Squalus acanthias by gel-filtration and ion-exchange chromatography. It had approximately 1% of the potency of mammalian alpha-MSH on bioassays in vitro on frog skin and dogfish skin. Sequence analysis revealed it to be a hexadecapeptide with the following primary structure: Asp-Gly-Asp-Asp-Tyr-Lys-Phe-Gly-His-Phe-Arg-Trp-Ser-Val-Pro-Leu. It appears to be related to the beta-MSH species of mammalian species but has only the sequence -His-Phe-Arg-Trp- in common with the heptapeptide core -Met-Glu-His-Phe-Arg-Trp-Gly- which is characteristic not only of the MSH peptides but also of the adrenocorticotrophins and lipotrophins studied so far. An alpha-MSH was also isolated, 50% of which was amidated at the C-terminus group. Sequence data from this study taken in conjunction with those from a previous study (Lowry & Chadwick, 1970b) revealed it to be a tridecapeptide which is identical with the N-terminal sequence of dogfish adrenocorticotrophin.
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94
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Scott AP, Lowry PJ, Bennett HP, McMartin C, Ratcliffe JG. Purification and characterization of porcine corticotrophin-like intermediate lobe peptide. J Endocrinol 1974; 61:369-80. [PMID: 4366117 DOI: 10.1677/joe.0.0610369] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
SUMMARY
Pig posterior pituitary lobe powder contains a peptide structurally identical to the 18–39 portion of porcine adrenocorticotrophin (ACTH). Its extraction by several different procedures is described and its susceptibility to degradation in the presence of 5% acetic acid has been noted. This degradation has been ascribed to the presence of acid proteases in the acetone-dried powder of the posterior pituitary lobe. The peptide has been isolated by chromatography on Biogel P6 and DEAE-cellulose, and characterized by enzyme fragmentation studies. It resembles the peptide isolated from rat neurointermediate lobes termed 'corticotrophin-like intermediate lobe peptide' and it is suggested that it is derived by the intracellular cleavage of ACTH in the pars intermedia cells, with subsequent formation of α-melanocyte-stimulating hormone from the other adrenocorticotrophic fragment.
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95
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Bennett HP, Bullock G, Lowry PJ, McMartin C, Peters J. Fate of corticotrophins in an isolated adrenal-cell bioassay and decrease of peptide breakdown by cell purification. Biochem J 1974; 138:185-94. [PMID: 4362738 PMCID: PMC1166194 DOI: 10.1042/bj1380185] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
1. The fate of corticotrophins in a trypsin-dispersed rat adrenal-cell assay system was investigated with a view to establishing whether differences in the rate of inactivation might contribute to potency differences observed between analogues. 2. Corticotrophin-(1-24)-tetracosapeptide and to a lesser extent synthetic 1-39 corticotrophins were found to be inactivated during incubation with cell suspension. 3. Peptide fragments were isolated by using [[(3)H(2)]Tyr(23)]corticotrophin-(1-24)- tetracosapeptide as a marker. The fragments indicate a peptidase with a predominantly tryptic specificity. 4. The peptidase is present in the extracellular fluid and is released from cells when they are damaged. 5. Cells were fractionated on an albumin gradient. Cells from the zona fasciculata and the zona intermedia or reticularis were present in fractions which produced fluorogenic steroids in response to corticotrophin. 6. Purification of the cells by centrifugation through albumin decreased degradation by peptidases, so that if the assay is carried out with a dilute suspension of purified cells peptide breakdown should not affect the observed potencies of adrenocorticotrophin analogues. 7. No binding of [[(3)H(2)]Tyr(23)]corticotrophin-(1-24)- tetracosapeptide to cells could be detected at low concentrations of the peptide. This indicated that less than 120 receptors/cell are occupied during stimulation by a dose that would elicit approx. 80% of the maximal response.
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96
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Scott AP, Ratcliffe JG, Rees LH, Landon J, Bennett HP, Lowry PJ, McMartin C. Pituitary peptide. NATURE: NEW BIOLOGY 1973; 244:65-7. [PMID: 4352887 DOI: 10.1038/newbio244065a0] [Citation(s) in RCA: 123] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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97
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Scott AP, Bennett HP, Lowry PJ, McMartin C, Ratcliffe JG. Characterization of corticotrophin-like intermediate lobe peptides from rat and pig pituitaries, and identification of alpha-melanocyte-stimulating hormone in the rat pituitary. J Endocrinol 1973; 58:xv. [PMID: 4352947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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98
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Bennett HP, Lowry PJ, McMartin C. Confirmation of the 1-20 amino acid sequence of human adrenocorticotrophin. Biochem J 1973; 133:11-3. [PMID: 4352834 PMCID: PMC1177665 DOI: 10.1042/bj1330011] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The tryptic fragments of natural human adrenocorticotrophin, were separated by countercurrent distribution and a correction in positions 25, 26, 27 and 30 was made by Riniker et al. (1972) in a study of the fragment containing residues 22-39. We have purified the remaining tryptic fragments, namely residues 1-8, 9-15, 16-21 and 17-21, by using ion-exchange chromatography on CM-cellulose and have carried out sequence determination by using the subtractive Edman degradation procedure and digestion with aminopeptidase M and carboxypeptidase B. These results have confirmed the proposed sequence for human adrenocorticotrophin in regions 6-7, 10-14 and 17-20, which had previously been arrived at only by analogy with the invariant sequence found in the three other mammalian adrenocorticotrophin species that had been investigated.
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99
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Ratcliffe JG, Scott AP, Bennett HP, Lowry PJ, McMartin C, Strong JA, Walbaum PR. Production of a corticotrophin-like intermediate lobe peptide and of corticotrophin by a bronchial carcinoid tumour. Clin Endocrinol (Oxf) 1973; 2:51-5. [PMID: 4358777 DOI: 10.1111/j.1365-2265.1973.tb03484.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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100
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Scott AP, Bennett HP, Lowry PJ, McMartin C, Ratcliffe JG. Coriticotrophin-like intermediate lobe peptide--a new pituitary and tumour peptide. J Endocrinol 1972; 55:xxxvi-xxxv. [PMID: 4344243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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