Parathyroid hormone (PTH) fragments relax the guinea-pig trachea in vitro

1983 ◽  
Vol 61 (11) ◽  
pp. 1324-1328 ◽  
Author(s):  
Y. C. Yen ◽  
May C. M. Yang ◽  
Alexander D. Kenny ◽  
Peter K. T. Pang
Keyword(s):  
Amino Acids ◽  
Hydrogen Peroxide ◽  
Parathyroid Hormone ◽  
Guinea Pig ◽  
Phosphodiesterase Inhibitor ◽  
Blocking Agent ◽  
No Inhibition ◽  
Per Se ◽  
Bovine Parathyroid Hormone

Synthetic bovine parathyroid hormone fragment containing the N-terminal 1 – 34 amino acids (bPTH-(1 – 34)) relaxed the guinea-pig trachea constricted with histamine in vitro. Peptides with bovine and human sequences purchased from Peninsula Laboratories and Beckman Bioproducts produced similar effects. Substitution of methionine in positions 8 and 18 by norleucine did not affect this property of bPTH-(1 – 34). However, when the methionines were oxidized by treating the peptide with hydrogen peroxide, the peptide could no longer produce relaxation in the trachea. Oxidation of the methionine-replaced analog did not affect the action of the peptide on the trachea. It seems that the methionines per se are not necessary, but once oxidized the conformation of the molecule may be sufficiently altered to affect its ability to relax the trachea. While propranolol can block the relaxing action of isoproterenol, this blocking agent produces no inhibition of the bPTH-(1 – 34) effect. This action of PTH on the trachea may be related to cAMP because isobutyryl-methylxanthine, a phosphodiesterase inhibitor, potentiates and imidazole, a phosphodiesterase stimulator, inhibits the trachea relaxing action of bPTH-(1 – 34).

Experimental parathyroid hormone deficiency produced by injection of antibodies to bovine parathyroid hormone

1968 ◽  
Vol 46 (3) ◽  
pp. 441-448 ◽  
Author(s):  
Sang Whay Kooh ◽  
Donald Fraser
Keyword(s):  
Parathyroid Hormone ◽  
Guinea Pig ◽  
Guinea Pigs ◽  
Specific Binding ◽  
Plasma Calcium ◽  
Hormone Deficiency ◽  
Similar Degree ◽  
Parathyroid Extract ◽  
Bovine Parathyroid Hormone

Antiserum to bovine parathyroid hormone (Anti-PTH) was produced in guinea pigs by repeated subcutaneous injections of purified bovine PTH with Freund's adjuvant. Specific binding of PTH with Anti-PTH was demonstrated in vitro by a two-antibody system. Anti-PTH was administered intravenously to three species of animals. Within 8 h, rats had developed a decrease in plasma calcium and an increase in plasma phosphorus concentrations, physiological changes characteristic of the PTH deficiency state. A similar degree of hypocalcemia occurred in rabbits. Some of the animals injected with Anti-PTH died within 24 h; in survivors, the hypoparathyroid state was transient and recovery occurred within 24 h. Equivalent amounts of Anti-PTH had no effect on the levels of plasma calcium in normal guinea pigs. Injections of parathyroid extract to rats, rabbits, and guinea pigs caused a hypercalcemic response. Since antibodies produced in the guinea pig to bovine PTH neutralized the physiological action of rat and rabbit PTH, but did not neutralize that of guinea pig PTH, it is concluded that bovine, rat, and rabbit PTH are immunologically similar, but that guinea pig PTH is dissimilar. However, the hormones of all four species have a common attribute that determines biological activity.

Synthesis of enkephalins by guinea-pig striatum in vitro

1979 ◽  
Vol 205 (1159) ◽  
pp. 199-207 ◽  
Keyword(s):  
Amino Acids ◽  
Guinea Pig ◽  
Lag Period ◽  
Time Required

A method for obtaining incorporation of labelled amino acids into enkephalins of guinea-pig striatum in vitro and isolating the labelled enkephalins is described. The incorporation of [ 3 H]tyrosine increases with time after a delay of 2 h. Cycloheximide added during this time, but not at later stages, inhibits incorporation. The results indicate that the enkephalins are produced locally, probably by ribosomal synthesis. The lag period may be due to the time required for the synthesis of precursors and their conversion to the enkephalins.

Effects on Bone In Vitro of Bovine Parathyroid Hormone and Synthetic Fragments Representing Residues 1–34, 2–34 and 3–34

1976 ◽  
Vol 3 (1) ◽  
pp. 21-35 ◽  
Author(s):  
M. P. M. Herrmann-Erlee ◽  
J. N. M. Heersche ◽  
J. W. Hekkelman ◽  
P. J. Gaillard ◽  
G. W. Tregear ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Bovine Parathyroid Hormone

ACQUIRED RESISTANCE TO PARATHYROID HORMONE

1976 ◽  
Vol 83 (2) ◽  
pp. 321-328 ◽  
Author(s):  
Tushar K. Sinha ◽  
Sherry F. Queener ◽  
Norman H. Bell ◽  
Sarah Larson
Keyword(s):  
Parathyroid Hormone ◽  
Renal Cortex ◽  
Acquired Resistance ◽  
Terminal Portion ◽  
Short Term ◽  
Clinical Resistance ◽  
Term Administration ◽  
Parathyroid Extract ◽  
Bovine Parathyroid Hormone

ABSTRACT Studies are presented in a patient with pseudohypoparathyroidism who showed a partial response to parathyroid extract. Resistance to the extract was observed after its short-term administration for the fourth time. Serum from the patient contained antibodies of the γG globulin class which bound 125I-labelled bovine parathyroid hormone. Prior incubation of parathyroid hormone with the serum prevented the activation in vitro of adenylate cyclase from pork renal cortex. The antibodies were directed primarily toward the C-terminal portion of the molecule. Thus, clinical resistance to parathyroid hormone is attributed to specific antibodies.

EFFECTS OF LOW CONCENTRATIONS OF THYROID STIMULATING HORMONE: PHARMACOLOGICAL EXPERIMENTS IN VITRO

1970 ◽  
Vol 64 (1) ◽  
pp. 133-149 ◽  
Author(s):  
M.-L. Desbarats-Schönbaum ◽  
E. A. Sellers ◽  
Malle Laansoo ◽  
Eva Koves ◽  
E. Schönbaum
Keyword(s):  
Guinea Pig ◽  
Thyroid Tissue ◽  
Phosphodiesterase Inhibitor ◽  
Thyroid Stimulating Hormone ◽  
Low Concentration ◽  
Low Concentrations ◽  
Stimulating Hormone

ABSTRACT In guinea pig thyroid tissue incubated at 25°C for forty hours the binding (organification) of iodide appears to be the step most sensitive to TSH. Binding is independent of uptake in this system and physiological doses of TSH can stimulate binding while uptake is partially inhibited. At a suitably low concentration of PTU, the addition of TSH can counteract the effect of this drug. At less than maximal concentrations, the effects of TSH and theophylline (a phosphodiesterase inhibitor) are additive, which supports the hypothesis that TSH acts by stimulating the production of cyclic 3′,5′-AMP. The effect of TSH appears to be exerted equally on any iodide present in the thyroid at the beginning of, or taken up during, incubation in vitro. In this system deiodination has been excluded as a major complicating factor.

scholarly journals Immunoassay of serum polypeptide hormones by using 125I-labelled anti(-immunoglobulin G) antibodies

1975 ◽  
Vol 145 (3) ◽  
pp. 607-616 ◽  
Author(s):  
P Beck ◽  
H Nicholas
Keyword(s):  
Growth Hormone ◽  
Parathyroid Hormone ◽  
Guinea Pig ◽  
Human Growth Hormone ◽  
Immunoglobulin G ◽  
Human Growth ◽  
Bovine Insulin ◽  
Polypeptide Hormone ◽  
Polypeptide Hormones ◽  
Bovine Parathyroid Hormone

1. A technique for indirectly labelling antibodies to polypeptide hormones, by combining them with radioactively labelled anti-(immunoglobulin G) is described. (a) 125I-labelled anti-(rabbit immunoglobulin G) and anti-(guinea-pig immunoglobulin G) antibodies with high specific radioactivity were prepared after purification of the antibodies on immunoadsorbents containing the respective antigens. (b) Rabbit immunoglobulin G antibodies to human growth hormone, porcine glucagon and guinea-pig immunoglobulin G antibodies to bovine insulin and bovine parathyroid hormone were combined with immunoadsorbents containing the respective polypeptide hormone antigen. (c) The immunoglobulin G antibodies to the polypeptide hormones were reacted with 125-I-labelled anti-(immunoglobulin G) antibodies directed against the appropriate species of immunoglobulin G,and the anti-hormone antibodies were combined with the hormone-containing immunoadsorbent. (d) 125I-labelled anti-(immunoglobulin G) antibodies and anti-hormone antibodies were simultaneously eluted from the hormone-containing immunoadsorbent by dilute HCl, pH 2.0. After elution the anti-(immunoglobulin G) antibodies and antihormone antibodies were allowed to recombine at pH 8.0 and 4 degrees C. 2. The resultant immunoglobulin G-anti-immunoglobulin G complex was used in immunoradiometric (labelled antibody) and two-site assays of the respective polypeptide hormone. 3. By using these immunoassays, concentrations down to 90pg of human growth hormone/ml, 100 pg of bovine insulin/ml, 80 pg of bovine parathyroid hormone/ml and 150 pg of glucagon/ml were readily detected. Assays of human plasma for growth hormone and insulin by these methods showed good agreement with results obtained by using a directly 125I-labelled anti-hormone antibody in an immunoradiometric assay of human growth hormone or by radioimmunoassay of human insulin. 4. The method described allows immunoradiometric or two-site assays to be performed starting with as little as 450 ng of polypeptide hormone-antibody protein. An additional advantage of the method is that a single iodination of the readily available antibodies to immunoglobulin G allows the establishemnt of several polypeptide hormone assays

Sulfur-free parathyroid hormone analogs containing D-amino acids: biological properties in vitro and in vivo

Biochemistry ◽  
1981 ◽  
Vol 20 (25) ◽  
pp. 7246-7250 ◽  
Author(s):  
Michael Rosenblatt ◽  
Marc D. Coltrera ◽  
Gary L. Shepard ◽  
D. A. Gray ◽  
John A. Parsons ◽  
...  
Keyword(s):  
Amino Acids ◽  
Parathyroid Hormone ◽  
Biological Properties ◽  
Hormone Analogs
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