Radioimmunoassay of canine growth hormone

1981 ◽  
Vol 98 (4) ◽  
pp. 514-520 ◽  
Author(s):  
J. E. Eigenmann ◽  
R. Y. Eigenmann
Keyword(s):  
Growth Hormone ◽  
Rhesus Monkeys ◽  
Low Dose ◽  
Cross Reactivity ◽  
Gel Chromatography ◽  
Assay Sensitivity ◽  
Standard Curve ◽  
Straight Line ◽  
Plasma Gh ◽  
Line Fitting

Abstract. A sensitive radioimmunoassay (RIA) for canine growth hormone (GH) was developed. Antibodies were elicited in rhesus monkeys. One antiserum exhibited a working titer at a dilution of 1:500000. Radioiodination was performed enzymatically employing lactoperoxidase. Logit-log transformation and least squares fitting resulted in straight line fitting of the standard curve between 0.39 and 50 ng/ml. Formation of largemolecular [12SI]GH during storage caused diminished assay sensitivity. Therefore [125I]GH was re-purified by gel chromatography. Using this procedure, high and reproducible assay sensitivity was obtained. Tracer preparations were used for as long as 3 months after iodination. Diluted plasma from normal and acromegalic dogs resulted in a dose-response curve parallel to the standard curve. Canine prolactin exhibited a cross-reactivity of 2%. The within-assay coefficient of variation (CV) was 3.8 and the between-assay CV was 7.2%. Mean plasma GH concentration in normal dogs was 1.92 ± 0.14 ng/ml (mean ± sem). GH levels in acromegalic dogs were appreciably higher. Insulin-induced hypoglycaemia, arginine and ornithine administration resulted in inconsistent and sluggish GH increment. A better response was obtained by injecting a low dose of clonidine. Clonidine administration to hypopituitary dogs resulted in absent or poor GH increment.

Growth hormone responses to low-dose physostigmine administration: functional sex differences (sexual diergism) between major depressives and matched controls

2003 ◽  
Vol 33 (4) ◽  
pp. 655-665 ◽  
Author(s):  
R. T. RUBIN ◽  
S. A. ABBASI ◽  
M. E. RHODES ◽  
R. K. CZAMBEL
Keyword(s):  
Growth Hormone ◽  
Sex Differences ◽  
Side Effects ◽  
Low Dose ◽  
Hormone Secretion ◽  
Saline Control ◽  
Similar Degree ◽  
Gh Secretion ◽  
Hormone Responses ◽  
Plasma Gh

Background. Considerable endocrine and non-endocrine evidence supports the hypothesis of increased cholinergic activity relative to noradrenergic activity in major depression. We previously reported functional sex differences (sexual diergism) in hypothalamo–pituitary–adrenal cortical (HPA) hormone responses to the administration of low-dose physostigmine (PHYSO), a cholinesterase inhibitor, in 12 female and eight male unipolar major depressives and 12 female and eight male individually matched control subjects. Because growth hormone (GH) secretion also is influenced by cholinergic mechanisms, we measured GH in the samples from this study.Method. Subjects underwent four test sessions 5–7 days apart: PHYSO (8 μg/kg i.v.), arginine vasopressin (AVP) (0·08 U/kg i.m.), PHYSO+AVP and saline control. The AVP was administered as a second stimulus to HPA axis hormone secretion. PHYSO and AVP produced no side-effects in about half the subjects and predominantly mild side-effects in the other half, with no significant patient–control differences. Point biserial correlations between side-effects (absent or present) after PHYSO and the corresponding GH responses were non-significant in all groups.Results. Afternoon baseline GH was significantly higher in the women than in the men, but it was not significantly different between the female or the male patients and their respective matched controls. AVP administration had no effect on GH. PHYSO administration acutely stimulated GH secretion, to a similar degree in the women and men. The depressed patients as a group had a significantly greater average post-PHYSO GH response than did their controls, with a trend toward a significant sex×diagnosis interaction: The female depressives had a significantly greater GH response than their female controls, whereas the male depressives had a similar GH response as their male controls.Conclusions. These findings suggest sexual diergism (functional sex differences) in baseline and cholinergically stimulated plasma GH measures between major depressives and matched normal controls.

A radioimmunoassay for oncorhynchid growth hormone targeted to the physiological range

1994 ◽  
Vol 72 (10) ◽  
pp. 1155-1161 ◽  
Author(s):  
Timothy J. Kieffer ◽  
Phil J. Schieldrop ◽  
Ewen McLean ◽  
Edward M. Donaldson ◽  
John C. Brown
Keyword(s):  
Growth Hormone ◽  
Rainbow Trout ◽  
Chum Salmon ◽  
Coho Salmon ◽  
Full Range ◽  
Rabbit Antiserum ◽  
Hormone Treatment ◽  
Cross Reactivity ◽  
Standard Curve ◽  
Wide Range

This study describes the development of an oncorhynchid growth hormone (GH) radioimmunoassay using recombinant chum salmon GH (rsGH) and a rabbit antiserum (TJK-1) raised against this recombinant material. The assay was designed to measure the wide range of circulating immunoreactive GH (IRGH) levels in Pacific salmonids, resulting in a standard curve capable of accurately determining plasma levels, of IRGH from 0.5 to 250 ng/mL without dilution. The assay ED50 and ED90 values averaged 13.1 and 0.5 ng/mL, respectively. This radioimmunoassay specifically recognizes oncorhynchid IRGH, showing no cross-reactivity with recombinant porcine and bovine GH, or natural chum salmon prolactin at concentrations up to 10 μg/mL. Curves approximately parallel to the standard curve were obtained with purified natural coho salmon GH and plasma from chinook salmon. Recovery of rsGH from plasma was complete over the full range of the standard curve. Intra- and inter-assay coefficients of variation were 6.0 and 12.9%, respectively. Plasma IRGH levels in fed coho salmon were 30.6 ± 5.3 ng/mL, while those in fish starved for 2 weeks were 132.9 ± 53.9 ng/mL. Starvation for an additional 4 weeks had no significant effect. Plasma IRGH levels in control rainbow trout injected with saline were significantly higher 45 min post-injection. In contrast, fish injected with recombinant porcine GH exhibited no elevation in IRGH. It is speculated that exogenous GH inhibits the production of endogenous GH.Key words: recombinant chum growth hormone, coho growth hormone, rainbow trout growth hormone, growth hormone treatment.

Evaluation of hippocampus in rhesus monkeys after chronic (1-year) inhalation exposure to marijuana: I. Electron microscopy

1990 ◽  
Vol 48 (3) ◽  
pp. 398-399
Author(s):  
A.M. Andrews ◽  
S.W. Wilson ◽  
A.C. Scallet ◽  
S.F. Ali ◽  
J. Bailey ◽  
...  
Keyword(s):  
Synaptic Vesicles ◽  
Rhesus Monkeys ◽  
Low Dose ◽  
Inhalation Exposure ◽  
Synaptic Cleft ◽  
High Dose ◽  
Withdrawal Time ◽  
Treatment Groups ◽  
Ultrastructural Evidence ◽  
Male Rhesus

Exposure of rhesus monkeys (Macaca mulatta) to marijuana via inhalation or to intravenous delta-9-tetrahydrocannabinol (THC), reportedly caused ultrastructural evidence of increased synaptic width. Chronic marijuana smoke in a single rhesus monkey examined after a six month withdrawal time caused ultrastructure changes in the septal, hippocampal and amygdala regions; the synaptic cleft was widened, electron opaque material was found in the cleft and in the pre- and postsynaptic regions, with some clumping of the synaptic vesicles. The objective of our study was to assess neuropathological alterations produced by chronic inhalation of marijuana smoke.Nineteen male rhesus monkeys, 3-5 years of age and weighing 3-8 kg, were divided into four treatment groups: a) sham control, b) placebo smoke (7 days/ week) c) low dose marijuana (2 times/week with 5 days/week sham) and d) high dose marijuana (7 times/week). A smoke exposure consisted of smoke from one cigarette (2.6% THC) burned down to 10 mm butt length. Smoke was administered via smoke generator (ADL II, Arthur D. Little, Inc. Cambridge, MA) and nose-mouth only masks (local production) equipped with one-way valves.

scholarly journals Circulating levels of growth hormone in postural orthostatic tachycardia syndrome

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Madeleine Johansson ◽  
Fabrizio Ricci ◽  
Janin Schulte ◽  
Margaretha Persson ◽  
Olle Melander ◽  
...  
Keyword(s):  
Heart Rate ◽  
Growth Hormone ◽  
Orthostatic Intolerance ◽  
High Sensitivity ◽  
Symptom Assessment ◽  
Postural Orthostatic Tachycardia Syndrome ◽  
Daily Life Activities ◽  
Median Plasma ◽  
Symptom Assessment Scale ◽  
Plasma Gh

AbstractPostural orthostatic tachycardia syndrome (POTS) is a cardiovascular autonomic disorder with poorly understood etiology and underlying pathophysiology. Since cardiovascular morbidity has been linked to growth hormone (GH), we studied GH levels in patients with POTS. We conducted an age-sex-matched case–control study in patients with POTS (age 31 ± 9 years; n = 42) and healthy controls (32 ± 9 years; n = 46). Plasma GH levels were measured using high-sensitivity chemiluminescence sandwich immunoassay. The burden of orthostatic intolerance symptoms was assessed by the Orthostatic Hypotension Questionnaire (OHQ), consisting of a symptom assessment scale (OHSA) and a daily activity scale (OHDAS). POTS patients had significantly higher composite OHQ score than controls, more symptoms and less activity. Supine heart rate and diastolic blood pressure (BP), but not systolic BP, were significantly higher in POTS. Median plasma GH levels were significantly lower in POTS (0.53 ng/mL) than controls (2.33 ng/mL, p = 0.04). GH levels were inversely related to OHDAS in POTS and supine systolic BP in POTS and controls, but not heart rate neither group. POTS is associated with lower GH levels. Impairment of daily life activities is inversely related with GH in POTS. A higher supine diastolic BP is inversely associated with GH levels in POTS and healthy individuals.

Low-dose growth hormone in adult home parenteral nutrition–dependent short bowel syndrome patients: A positive study

2003 ◽  
Vol 124 (2) ◽  
pp. 293-302 ◽  
Author(s):  
David Seguy ◽  
Kouroche Vahedi ◽  
Nathalie Kapel ◽  
Jean–Claude Souberbielle ◽  
Bernard Messing
Keyword(s):  
Growth Hormone ◽  
Parenteral Nutrition ◽  
Short Bowel Syndrome ◽  
Low Dose ◽  
Home Parenteral Nutrition ◽  
Short Bowel ◽  
Positive Study

The Circulating Growth Hormone (GH)-Binding Protein Complex: A Major Constituent of Plasma GH in Man*

Endocrinology ◽  
1988 ◽  
Vol 122 (3) ◽  
pp. 976-984 ◽  
Author(s):  
GERHARD BAUMANN ◽  
KLAUS AMBURN ◽  
MELISSA A. SHAW
Keyword(s):  
Growth Hormone ◽  
Protein Complex ◽  
Binding Protein ◽  
Major Constituent ◽  
Plasma Gh

Straight-Line Fitting with an HP-45 Calculator

1974 ◽  
Vol 42 (3) ◽  
pp. 253-253
Author(s):  
W. C. Elmore
Keyword(s):  
Straight Line ◽  
Line Fitting

Growth hormone and somatostatin gene expression in pituitary adenomas with active acromegaly and minimal plasma growth hormone elevation

1990 ◽  
Vol 122 (6) ◽  
pp. 745-752 ◽  
Author(s):  
Patrick Pagesy ◽  
Jacques Y. Li ◽  
Françoise Rentier-Delrue ◽  
Olivier Delalande ◽  
Yves Le Bouc ◽  
...  
Keyword(s):  
Growth Hormone ◽  
Northern Blot Analysis ◽  
Secretory Activity ◽  
Ultrastructural Level ◽  
Wide Range ◽  
Igf I ◽  
Gh Gene ◽  
Basal Plasma ◽  
Active Acromegaly ◽  
Plasma Gh

Abstract. Some patients with active acromegaly have elevated plasma IGF-I concentrations with only minimal elevation of plasma GH. We compared adenomatous GH and SRIH expression in 3 such patients (patients No. 1, 2 and 3; basal plasma GH level < 4 μg/l) and in 3 acromegalic patients with high basal plasma GH level (patients No. 4, 5 and 6; 51.7 ± 16.1 μg/l, mean ± sem). By immunocytochemistry, all the tumours proved to be somatotropic adenomas. At the ultrastructural level, signs of low secretory activity were observed in adenomas from patients No. 2 and 3. Perifused adenoma cells of patients No. 1, 2 and 3 released very little GH compared with those of patients No. 4, 5 and 6 (1± 0.37 vs 51.5± 34.1 μg · (10−6 cells) · min−1, p< 0.001). Adenoma SRIH content was 65.7 and 30.6 pg/mg proteins in patients No. 1 and 2, whereas it was undetectable in the others (patients No. 4, 5 and 6). Northern blot analysis showed that the GH gene was poorly expressed in the adenomas from patients No. 1, 2 and 3 compared with the adenomas from patients No. 4, 5 and 6. SRIH mRNA was detected in all 6 adenomas. However, the signal was more intense in the adenomas from patients No. 1, 2 and 3 than in those from patients No. 4, 5 and 6. In conclusion, because of the variability of the biosynthetic and secretory potential of the somatotropic adenomas, patients harbouring this type of pituitary tumours can exhibit a wide range of plasma GH levels. In acromegaly with minimal elevation of plasma GH, the synthesis of SRIH by the adenoma cells themselves could play a role in the inhibition of GH expression.

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