Thyrotrophin releasing hormone and related peptides in canine tissues

1983 ◽  
Vol 98 (3) ◽  
pp. 299-306 ◽  
Author(s):  
A. E. Pekary ◽  
Melvyn Richkind ◽  
J. M. Hershman
Keyword(s):  
Total Concentration ◽  
Exchange Chromatography ◽  
Cation Exchange Chromatography ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Cation Exchangers ◽  
Binding Substance ◽  
Exclusion Chromatography ◽  
Liver Homogenates ◽  
Dog Liver

Thyrotrophin releasing hormone (TRH)-immunoreactive peptides have been quantified in canine serum, hypothalamus, liver, pancreas, adrenal, thyroid, prostate, testis, epididymis and semen by TRH radioimmunoassay, SP-Sephadex C-25 cation exchange chromatography, Sephadex G-10 exclusion chromatography and high pressure liquid chromatography. The total concentration of TRH and TRH-like peptides was highest in the hypothalamus, followed by liver, adrenal, pancreas, thyroid, prostate, epididymis, testis and serum. All of the TRH immunoreactivity (TRH-IR) within extracts of the hypothalamus was due to TRH. On the other hand, nearly all of the TRH-IR of extracts of liver, thyroid, prostate, epididymis, testis and semen was due to TRH-homologous peptides. Adrenal and pancreatic extracts contained a greater proportion of TRH in relation to the TRH-homologous peptides. Extracts of dog serum and semen were found to contain a TRH-binding substance which reduced the retention of added TRH by cation exchangers. The half-time of disappearance (t½) of synthetic TRH incubated at 23 °C in 10% (w/v) homogenates in 0·15 m-NaCl–0·05 m-phosphate buffer, pH 7·5, ranged from 22±10 (s.d.) min for liver to 120 ±58 min for thyroid. The short t½ for TRH added to dog liver homogenates contrasted with a previous report that dog liver is essentially free of TRH-degrading activity.

ABSENCE OF PYROGLUTAMYL-N3im-METHYL-HISTIDYL-PROLINEAMIDE (METHYL-THYROTROPHIN RELEASING HORMONE) IN THE RAT HYPOTHALAMUS

1978 ◽  
Vol 77 (3) ◽  
pp. 405-408 ◽  
Author(s):  
A. E. PEKARY ◽  
J. E. MORLEY ◽  
J. M. HERSHMAN
Keyword(s):  
Cation Exchange ◽  
Exchange Chromatography ◽  
Mammalian Brain ◽  
Synthetic Analogue ◽  
Cation Exchange Chromatography ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Rat Hypothalamus

Pyroglutamyl-N3im-methyl-histidyl-prolineamide (methyl-thyrotrophin releasing hormone, methyl-TRH) is a potent synthetic analogue of TRH. N3im-Methyl-histidine is present in mammalian brain and it has been suggested that methyl-TRH is a physiological releasing hormone normally present in the hypothalamus. A non-gradient cation-exchange chromatography system that uses SP-Sephadex C-25 and completely resolves methyl-TRH and TRH has been developed. Because methyl-TRH cross-reacts in the immunoassay for TRH, this assay was used to measure TRH and methyl-TRH in the chromatographic fractions. By this means it has been demonstrated that the amount of methyl-TRH present in the rat is less than 0·025 ng/hypothalamus.

A modified fractionation procedure for avian erythrocyte histones

1969 ◽  
Vol 47 (12) ◽  
pp. 1121-1123 ◽  
Author(s):  
G. H. M. Adams ◽  
J. M. Neelin
Keyword(s):  
Cation Exchange ◽  
Exchange Chromatography ◽  
Cation Exchange Chromatography ◽  
Fractionation Procedure ◽  
Exclusion Chromatography ◽  
One Step ◽  
Avian Erythrocyte ◽  
Fractionation Method ◽  
Time Required

The fractionation method of Vidali and Neelin for avian erythrocyte histones was modified to reduce the time required to obtain clean fractions of serine-rich and arginine-rich histones. Histones were extracted from washed nuclei in one step with 0.20 M HCl. The lysine-rich and the moderately lysine-rich histones were fractionated by cation-exchange chromatography but the serine-rich and arginine-rich histones were eluted together. These histones were separated by subsequent exclusion chromatography.

Comparison of the histones from fish erythrocytes

1977 ◽  
Vol 55 (12) ◽  
pp. 1220-1227 ◽  
Author(s):  
Brian L. A. Miki ◽  
James M. Neelin
Keyword(s):  
Cation Exchange ◽  
Polyacrylamide Gel Electrophoresis ◽  
Exchange Chromatography ◽  
White Sucker ◽  
Cation Exchange Chromatography ◽  
Apparent Absence ◽  
Histone Fraction ◽  
Functional Homology ◽  
Diverse Species ◽  
Exclusion Chromatography

Because of contentions concerning the generality of cell-specific histone 5 (H5) in nucleated erythrocytes of species other than birds, the erythrocyte histones of carp, trout, perch, black crappie, and white sucker were studied under conditions which minimize proteolysis. All were examined by polyacrylamide gel electrophoresis, and histone 1 (H1) and H5 were purified by cation-exchange chromatography on Amberlite CG-50 and by exclusion chromatography through BioGel P60.A protein homologous to H5 could be isolated and identified from the mature erythrocytes of carp, trout, perch, and black crappie but not from white sucker. The relative amounts of H5 differed extensively and inversely in proportion to H1, implying some functional homology between these proteins. The extremely variable levels of H5, including its apparent absence from one species, suggests that typical H5 is not essential to the function or development of nucleated erythrocytes.Although H1 is the most divergent histone fraction, H5 is also highly variable. Fish erythrocyte H5 differs from avian H5 in relative electrophoretic mobility, ease of elution from Amberlite CG-50 cation-exchange columns, and amino acid composition. H5's from fish tend to have more threonine but less serine, arginine, glutamic acid, and histidine than avian H5's. Fish H5's are more diverse than avian H5's and resemble the H5 homologues from other extremely diverse species; thus avian H5 may be an extreme in specialization of an H1 subfraction.

STUDIES ON THE NATURE OF MAMMALIAN HYPOTHALAMIC THYROTROPHIN RELEASING HORMONE USING IMMUNOCHEMICAL, CHROMATOGRAPHIC AND ENZYMIC TECHNIQUES

1975 ◽  
Vol 65 (1) ◽  
pp. 83-90 ◽  
Author(s):  
S. L. JEFFCOATE ◽  
N. WHITE
Keyword(s):  
Ion Exchange ◽  
Human Plasma ◽  
Carboxymethyl Cellulose ◽  
Mammalian Species ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Normal Human Plasma ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Normal Human

SUMMARY Hypothalamic extracts from three mammalian species (rat, rabbit and sheep) were found to contain several ng of immunoreactive thyrotrophin releasing hormone (TRH)-like activity. This substance chromatographed on ion exchange chromatography (carboxymethyl cellulose) as a single peak that was indistinguishable from synthetic TRH. Hypothalamic TRH was also inactivated by normal human plasma at a rate (1·21–1·46%/μl plasma/h and 1·59–1·77%/50 μl plasma/min) similar to that of synthetic TRH (1·42%/μl plasma/h and 1·73%/50 μl plasma/min). This combination of chromatographic and enzymic techniques can be applied to the identification of immunoreactive TRH in body fluids.

The similarity of histones from turtle erythrocytes and liver

1981 ◽  
Vol 59 (4) ◽  
pp. 273-279 ◽  
Author(s):  
R. G. Rutledge ◽  
C. E. Shay ◽  
G. L. Brown ◽  
J. M. Neelin
Keyword(s):  
Gel Electrophoresis ◽  
Minor Component ◽  
Sea Turtle ◽  
Exchange Chromatography ◽  
The Other ◽  
Cation Exchange Chromatography ◽  
Mammalian Tissues ◽  
Exclusion Chromatography ◽  
A Minor ◽  
Molecular Exclusion Chromatography

Using the fresh-water "red-eared turtle" Pseudomys scriptans elegans, we have confirmed the existence of a minor component H1s among the lysine-rich histones of turtle erythrocytes by three forms of gel electrophoresis and two forms of chromatography. It was separated from the major components by both cation-exchange chromatography and molecular-exclusion chromatography and shown to differ slightly but significantly in content of several amino acids as well as being shorter than the other lysine-rich histones. Although its composition is close to that of the "tissue-specific" F1b of sea turtle erythrocytes, it is present in even greater relative amount in red-eared turtle livers. In most respects it resembles the satellite histone H10 of mammalian tissues. No unusual histones were observed among the perchloric acid insoluble histones of turtle erythrocytes.

Thyrotrophin-releasing hormone-related polypeptides in rabbit prostate and semen are different from those in rabbit hypothalamus

1989 ◽  
Vol 120 (1) ◽  
pp. 31-36 ◽  
Author(s):  
S. M. Cockle ◽  
J. M. Morrell ◽  
D. G. Smyth
Keyword(s):  
Prostate Gland ◽  
Trypsin Digestion ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
Related Peptide ◽  
Exclusion Chromatography

ABSTRACT TRH-related peptides were extracted from the hypothalamus and prostate gland of the rabbit. The peptides were fractionated by gel exclusion chromatography and located by trypsin digestion and radioimmunoassay with antibodies to TRH amide and TRH–Gly Lys. In the hypothalamus TRH-related peptides containing approximately 16 and 30 residues were observed: in these peptides the extensions to the TRH sequence were exclusively in the C-terminal direction. In addition, the three-residue form of TRH was also present. In the prostate complex, the predominant TRH-related peptide contained approximately 50 residues and the extension to the TRH tripeptide was on the N-terminal side; a three-residue form of immunoreactive TRH was also demonstrated. The same pattern of TRH-related peptides was shown to be present in rabbit semen. The results reveal the existence of a novel TRH-related polypeptide in the prostate and semen which does not occur in the hypothalamus. This peptide appears to undergo secretion. Journal of Endocrinology (1989) 120, 31–36

The thyrotrophin-releasing hormone (TRH)-like peptides in rat prostate are not formed by expression of the TRH gene but are suppressed by thyroid hormone

1992 ◽  
Vol 132 (2) ◽  
pp. 177-184 ◽  
Author(s):  
R. Bilek ◽  
P. J. Gkonos ◽  
M. A. Tavianini ◽  
D. G. Smyth ◽  
B. A. Roos
Keyword(s):  
High Performance ◽  
Polymerase Chain Reaction Amplification ◽  
Exchange Chromatography ◽  
Adult Rats ◽  
Thyrotrophin Releasing Hormone ◽  
Basic Group ◽  
Releasing Hormone ◽  
Significant Difference ◽  
Reaction Amplification ◽  
Rat Prostate

ABSTRACT Thyrotrophin-releasing hormone (TRH)-immunoreactive peptides were extracted from rat prostate and divided into two groups by mini-column cation exchange chromatography. The amounts of the peptides in each group were determined by radioimmunoassay with a TRH antiserum. The unretained peptides which lacked a basic group and the retained peptides which possessed a basic group were further purified by high-performance liquid chromatography. The unretained fraction was found to contain a series of TRH-immunoreactive peptides, one of which corresponded chromatographically to synthetic pGlu-Glu-Pro amide and another to pGlu-Phe-Pro amide. None of the TRH-immunoreactive peptides in either fraction exhibited the chromatographic behaviour of TRH. Additional evidence for the absence of TRH gene expression in the prostate was obtained by Northern blot analysis and by application of polymerase chain reaction amplification, which failed to reveal TRH mRNA. Furthermore the preproTRH-derived peptide, preproTRH(53–74), could not be detected by radioimmunoassay. The influence of thyroid status was investigated on the levels of the TRH-like peptides in the prostate. Adult rats were treated chronically with thyroxine (T4) or propylthiouracil (PTU) and the concentrations of the TRH-immunoreactive peptides were determined by chromatography and radioimmunoassay. Treatment with T4 caused the levels of the neutral and acidic TRH-like peptides to fall to approximately one-third of the levels in the controls. No significant difference from the controls was seen in the concentrations of the peptides in the prostates of rats rendered hypothyroid by administration of PTU. The results demonstrate that rat prostate contains TRH-immunoreactive peptides which are not derived from the TRH gene. It is concluded that the TRH-like peptides arise from one or more genes which are structurally distinct from that which codes for the TRH preprohormone. Since these peptides are amidated and their levels are sensitive to hormone administration, it is likely that they fulfil a biological function. Journal of Endocrinology (1992) 132, 177–184

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