OVARIAN BINDING AND INTRINSIC BIOLOGICAL ACTIVITY OF DESIALYLATED HUMAN CHORIONIC GONADOTROPHIN (ASIALO-hCG) IN IMMATURE SUPEROVULATED RATS

1979 ◽  
Vol 90 (2) ◽  
pp. 349-360 ◽  
Author(s):  
J. Odink ◽  
E. C. Brand ◽  
E. V. Van Hall
Keyword(s):  
Ascorbic Acid ◽  
Biological Activity ◽  
Hepatic Uptake ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Bilateral Nephrectomy ◽  
Uptake Studies

ABSTRACT The present study was undertaken to investigate the effect of desialylation on the intrinsic in vivo biological activity of hCG. To block the hepatic uptake of asialo-hCG we investigated asialo-orosomucoid. The biological activity of hCG and asialo-hCG was estimated with the ovarian ascorbic acid depletion assay (OAAD). The uptake studies were performed with [125I]hCG and [125I]asialo-hCG. Desialylation of hCG increased its hepatic uptake, almost completely abolished its ovarian uptake, and reduced its in vivo biological activity to less than 1 %. Administration of asialo-orosomucoid caused a reduction of the hepatic uptake of asialo-hCG to the level observed for hCG. The ovarian uptake increased, but was lower than observed for hCG, due to a considerably higher renal accumulation of asialo-hCG. The in vivo biological activity of asialo-hCG was approximately 1/5 of the activity of hCG when both were tested in the presence of asialo-orosomucoid. To exclude the interference of renal accumulation, binding and biological activity were also investigated after bilateral nephrectomy. The uptake of radioactivity in the ovaries following injection of [512I]asialo-hCG and asialo-orosomucoid was then almost the same as observed after injection of [125I]hCG alone. When both preparations were now tested in the presence of asialo-orosomucoid, the in vivo biological activity of asialohCG appeared to be approximately 1/3 of the value obtained for hCG. It is concluded that the intrinsic in vivo biological activity of hCG is lowered by desialylation.

EFFECT OF FREEZING AND THAWING AND OF DILUENT ON THE POTENCY OF HUMAN CHORIONIC GONADOTROPHIN IN THREE METHODS OF BIOASSAY

1969 ◽  
Vol 61 (1) ◽  
pp. 89-95
Author(s):  
Rudi Borth ◽  
Annette Menzi
Keyword(s):  
Ascorbic Acid ◽  
Biological Activity ◽  
Bovine Serum Albumin ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Prolonged Storage ◽  
Distilled Water ◽  
Uterine Weight ◽  
Freezing And Thawing ◽  
Repeated Freezing

ABSTRACT In a study designed as a factorial experiment, the biological activity of standard solutions of human chorionic gonadotrophin in distilled water (A), saline (B), 1 % bovine serum albumin (C), 0.5 % gelatin (D), and borate buffer of pH 9 (E) was investigated under four different conditions of freezing and thawing, using the following three methods of bioassay: ovarian ascorbic acid depletion in rats (OAAD), uterine weight in mice (UW), and ovarian hyperaemia in rats (OH). Repeated freezing and thawing and prolonged storage at -15°C did not affect the potency in any test. In the OAAD test, the potency was increased 4–5fold by D, and 2–3fold by C. In the OH test, E augmented the potency 2–3fold. These findings are of interest in the practice of bioassay, in studying mechanisms of response, and regarding administration for therapeutic purposes. Diluents which possess augmenting properties could be used to improve the sensitivity of a bioassay if standard and unknowns showed the same degree of augmentation.

A PITFALL IN THE OVARIAN ASCORBIC ACID DEPLETION ASSAY (OAAD): EFFECT OF UNILATERAL OVARIECTOMY, hCG AND ASIALO-hCG

1979 ◽  
Vol 91 (3) ◽  
pp. 538-544
Author(s):  
J. Odink ◽  
E. C. Brand ◽  
E. V. Van Hall
Keyword(s):  
Ascorbic Acid ◽  
Biological Activity ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Unilateral Ovariectomy ◽  
Assay Conditions

ABSTRACT The estimation of the effect of desialylation on the biological activity of human chorionic gonadotrophin (hCG), as determined in the ovarian ascorbic acid depletion assay (OAAD), according to the modification in which the animals are used twice, appeared to be dependent on the assay conditions. Animals which received hCG in the first assay (OAAD-1) gave higher potency estimates for hCG and asialo-hCG in the second assay (OAAD-2) than rats which received asialo-hCG in OAAD-1. The results of the experiments indicate that the ovarian sensitivity for hCG and asialo-hCG is increased after administration of hCG and unilateral ovariectomy and decreased after administration of asialo-hCG.

THE EFFECT OF 6 m UREA ON THE FOLLICLE-STIMULATING AND LUTEINIZING HORMONE ACTIVITIES OF VARIOUS GONADOTROPHIN PREPARATIONS

1962 ◽  
Vol 24 (2) ◽  
pp. 153-158 ◽  
Author(s):  
H. SCHMIDT-ELMENDORFF ◽  
J. A. LORAINE ◽  
E. T. BELL
Keyword(s):  
Ascorbic Acid ◽  
Biological Activity ◽  
Luteinizing Hormone ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Considerable Reduction ◽  
Mouse Uterus ◽  
Stimulating Hormone

SUMMARY The luteinizing hormone (LH), follicle-stimulating hormone (FSH) and 'total gonadotrophic' activities of various hormones have been studied following incubation with 6 m urea at 40° c for 24 hr. LH activity was estimated by the ovarian ascorbic acid depletion test in rats, FSH activity by the augmentation test in mice, and 'total gonadotrophic' activity by the mouse uterus test. Following incubation with 6 m urea the LH activities of NIH—LH, NIH—FSH, human chorionic gonadotrophin and Pergonal were almost completely destroyed, while the LH activity of pregnant mares' serum gonadotrophin (PMSG) was reduced to a smaller extent. The FSH activity of NIH—FSH was little affected by this form of treatment, but in the case of Pergonal a considerable reduction of FSH activity occurred. The 'total gonadotrophic' activity of NIH—FSH, PMSG and Pergonal was reduced after incubation with 6 m urea, the degree of inactivation being greatest in the case of Pergonal. After control incubations with water no appreciable loss of biological activity was observed with any hormone other than Pergonal.

The effect of galactose oxidase treatment on the hepatic binding and biological activity of desialylated human chorionic gonadotrophin

1980 ◽  
Vol 93 (2) ◽  
pp. 234-242 ◽  
Author(s):  
Egenius C. Brand ◽  
Jacobus Odink
Keyword(s):  
Biological Activity ◽  
Specific Binding ◽  
Hepatic Uptake ◽  
Galactose Oxidase ◽  
High Dose ◽  
Uptake Studies ◽  
Radioligand Receptor Assay ◽  
Galactosyl Residues

Abstract. 125I labelled desialylated hCG (asialo-hCG) was treated with galactose oxidase, in order to find out whether oxidation of the terminal galactosyl residues would diminish the hepatic uptake of asialo-hCG. Specific binding to the hepatic asialo-glycoprotein receptor was monitored in vitro by a rat liver radioligand receptor assay (RRA). Hormonal activities were compared by ovarian RRA and by in vitro bioassay. Uptake studies were done in superovulated immature rats. Galactose oxidase treatment had hardly any influence on the in vitro ovarian binding and biological activity of [125I]asialo-hCG. Binding in the liver RRA was virtually abolished. In vivo hepatic uptake, however, was considerably above the level of [125I]hCG, as was the uptake in the kidneys. The hepatic uptake was inhibited by the administration of a high dose of asialo-fetuin. It is concluded that oxidation of the terminal galactosyl residues reduces the binding of asialo-hCG to the hepatic asialo-glycoprotein receptor, without affecting its hormonal properties. The ovarian uptake in vivo, however, is still limited by the high hepatic and renal clearance.

THE PRECISION OF THE OVARIAN ASCORBIC ACID DEPLETION TEST FOR LUTEINIZING HORMONE

1963 ◽  
Vol 43 (1) ◽  
pp. 155-160
Author(s):  
Jørgen Falck Larsen ◽  
Christian Hamburger
Keyword(s):  
Ascorbic Acid ◽  
Luteinizing Hormone ◽  
Clinical Analysis ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin

ABSTRACT Various modifications of the Parlow test for luteinizing hormone (ovarian ascorbic acid depletion in rats) were tried. Human chorionic gonadotrophin was used instead of hypophyseal luteinizing hormone. The precision of the method was found to be so low, however, that the test could not be used for routine clinical analysis. The low precision found in this and other laboratories is thought to be due to the strains of rats used.

COMPARISON OF BIOASSAY AND IMMUNOASSAY OF HUMAN CHORIONIC GONADOTROPHIN IN URINE

1965 ◽  
Vol 50 (3) ◽  
pp. 335-344 ◽  
Author(s):  
Rudi Borth ◽  
Michel Ferin ◽  
Annette Menzi
Keyword(s):  
Biological Activity ◽  
Total Variation ◽  
Regression Line ◽  
Haemagglutination Inhibition ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Factorial Experiment ◽  
Serological Result ◽  
Pregnancy Urine ◽  
Acceptable Agreement

ABSTRACT In 39 samples of pregnancy urine, the concentration of human chorionic gonadotrophin (HCG) was estimated biologically by the ovarian hyperaemia reaction in rats, and serologically by the passive haemagglutinationinhibition technique. The results of the bioassays varied from 3 to 150 IU/ml, those of the immunoassays from 5 to 640 IU-eq./ml, and the correlation between the two (calculated for their logarithms) accounted for only 17 per cent of the total variation (r2 = 0.169, P ≈0.01). If the biological activity were estimated from a serological result and the appropriate regression line, the fiducial interval for P = 0.05 would extend from 17 to 610 per cent of the estimate. In a factorial experiment using three anti-HCG sera, three standard and three sensitizing preparations of HCG, the sensitivity of the serological system (expressed as the endpoint concentration in IU of HCG) varied considerably between the 27 combinations of the 3 factors, but there was no interaction between the latter. From these data and those of other authors, it is concluded that immunoassays based on haemagglutination inhibition cannot replace bioassays in the estimation of HCG, as distinct from its hypothetical metabolites or other related antigens, unless specificity has been demonstrated. The well-documented reliability of serological pregnancy tests is, of course, not in dispute. Attention is drawn to the fact that »statistically significant« correlation does not guarantee analytically acceptable agreement between two methods of assay.

ANTIGONADOTROPHIC PROFILE OF ANTISERA AGAINST HUMAN GONADOTROPHIN PREPARATIONS

1971 ◽  
Vol 67 (2) ◽  
pp. 262-276 ◽  
Author(s):  
P. Petrusz ◽  
C. Robyn ◽  
E. Diczfalusy
Keyword(s):  
Biological Activity ◽  
Luteinizing Hormone ◽  
Total Dose ◽  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Immunological Activity ◽  
Human Menopausal Gonadotrophin ◽  
Stimulating Hormone

ABSTRACT Forty-two antisera were prepared in rabbits against human chorionic gonadotrophin (HCG), human hypophysial gonadotrophin (HHG), human urinary luteinizing hormone (LH) and human menopausal gonadotrophin (HMG) preparations. The gonadotrophic profiles of the antigens were previously characterized by bioassay, immunoassay and bioimmunoassay methods. The 25 most potent antisera were tested in statistically valid bioassays for their HCG and follicle stimulating hormone (FSH) neutralizing activities as well as for their neutralizing potencies against the FSH-like activity present in HCG preparations. The anti-HCG/anti-FSH ratios of the anti-HCG sera tested varied between 6.2 and > 254, while those of the anti-HHG, anti-LH and anti-HMG sera were close to 2. It was found that the total dose of immunological activity (anti-HCG neutralizing and anti-FSH neutralizing potency) rather than that of the biological activity administered to the rabbits was decisive for obtaining antisera with high anti-HCG and anti-FSH titers. Immunization with a highly purified HCG preparation (> 17 000 IU/mg) resulted in antisera exhibiting lower anti-HCG/anti-FSH ratios than did immunization with partially purified preparations. A highly purified urinary LH preparation which did not contain any detectable FSH activity gave rise to antisera exhibiting anti-HCG/anti-FSH ratios of approximately 2.0. These highly purified HCG and LH preparations were shown previously to possess high anti-FSH neutralizing potencies (Petrusz et al. 1971b). Booster injections did not change significantly the quality or the titer of the antigonadotrophic sera studied. The HCG neutralizing potency of anti-HCG sera was approximately 3 times higher when assayed against a highly purified HCG preparation (> 17 000 IU/mg) as compared to potency estimates obtained against the laboratory standard of HCG (about 2000 IU/mg). It is suggested that consideration should be given to the establishment of standard preparations of antigonadotrophic sera. It is concluded that bioimmunoassays are more suitably than conventional bioassay methods for the assessment of the antigenic purity of human gonadotrophin preparations.

INHIBITION BY MELATONIN OF THE PITUITARY RESPONSE TO LUTEINIZING HORMONE RELEASING HORMONE IN VIVO

1978 ◽  
Vol 76 (3) ◽  
pp. 487-491 ◽  
Author(s):  
K. YAMASHITA ◽  
M. MIENO ◽  
T. SHIMIZU ◽  
ER. YAMASHITA
Keyword(s):  
Luteinizing Hormone ◽  
Carotid Artery ◽  
Anterior Pituitary ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Luteinizing Hormone Releasing Hormone ◽  
Releasing Hormone ◽  
Lh Rh ◽  
Lh Secretion

The rate of secretion of 17-oxosteroids by the testes of anaesthetized dogs in vivo was used as an index of LH secretion. Intracarotid injection of luteinizing hormone releasing hormone (LH-RH, 1, 5 or 10 μg/kg body wt) resulted in an increase in the testicular 17-oxosteroid secretion which was roughly proportional to the dose administered and which reached a maximum 60 min after the injection. Testicular output of 17-oxosteroids was unaffected by administration of melatonin (10 or 100 μg/kg body wt) into the carotid artery. When LH-RH (5 μg/kg) was injected into the carotid artery 3 h after intracarotid injection of melatonin (10 or 100 μg/kg), the testicular response to LH-RH was considerably diminished. Pretreatment with melatonin (100 μg/kg) did not alter the testicular response to human chorionic gonadotrophin (20 i.u./kg body wt) given i.v. It is concluded that melatonin may act directly on the anterior pituitary gland in dogs to inhibit the LH-RH-induced release of LH.

A COMPARISON BETWEEN CHORIONIC GONADOTROPHINS EXTRACTED FROM HUMAN, RHESUS MONKEY AND MARMOSET PLACENTAE

1972 ◽  
Vol 55 (2) ◽  
pp. 363-368 ◽  
Author(s):  
BRUCE HOBSON ◽  
LEIF WIDE
Keyword(s):  
Biological Activity ◽  
Rhesus Monkey ◽  
Human Placenta ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Antigenic Determinants

SUMMARY Evidence is provided to show that chorionic gonadotrophins extracted from the human, rhesus monkey and marmoset placentae have antigenic determinants in common. Similar slopes were obtained for these gonadotrophins in a radioimmunoassay for human chorionic gonadotrophin (HCG). The biological activity of the monkey gonadotrophins was neutralized by anti-HCG serum. When the gonadotrophic activity of the monkey placental extracts was assayed biologically and immunologically, using HCG as a standard, similar results were obtained. Higher values were obtained by the immunoassay than by the bioassay when extracts of human placenta were assayed using the same HCG standard.

Sign in / Sign up

Export Citation Format

Share Document