Estimation of the specific activity of radioiodinated gonadotrophins: comparison of three methods

We compared 3 methods for estimating the specific activity of radioiodinated gonadotrophins. Two of the methods (column recovery and isotopic dilution) gave similar results, while the third (autodisplacement) gave significantly higher estimations. In the autodisplacement method, B/T ratios, obtained when either labelled hormone alone, or labelled and unlabelled hormone, are added to the antibody, were compared as estimates of the mass of hormone iodinated. It is likely that immunologically unreactive impurities present in the labelled hormone solution invalidate such comparison.

Effect of constant light and darkness on pituitary and serum gonadotropin and sex hormone levels of parturient rats

Exposure of rats to continuous darkness throughout gestation produced a threefold increase in their serum prolactin and a moderate one in their serum LH levels on the day preceding delivery. Parallel decreases in pituitary prolactin and LH contents were experienced indicating enhanced release of the hormones. In the animals kept in constant light only prolactin release was increased before delivery, their LH levels were unaffected, although diminished pituitary contents due to decreased synthesis were evident. Following parturition the photo-induced prolactin levels in serum and pituitary disappeared, but the LH values of the rats exposed to both extremes of illumination persisted, in contrast to those of the control animals kept in alternating light (12 L : 12 D) whose values fell abruptly. Serum oestradiol was affected neither by darkness nor light but serum progesterone concentrations were depressed before delivery in the rats kept in darkness even more than in the control animals. Exposure to continuous darkness shortened the duration of gestation. The marked tendency to deliver during the daytime hours was not influenced by exposure to continuous darkness but was completely abolished by constant light. It is suggested that the strongly decreased serum progesterone levels--possibly brought about by the high prolactin concentrations observed before parturition--may be contributing to the earlier onset of delivery in the rats exposed to continuous darkness.

Influence of body weight on prolactin, estradiol and gonadotropin levels of obese and underweight women

Gonadotropins and prolactin were measured in 59 amenorrhoic pat. with highly different weights before and after i.v. administration of 25 microgram LHRH and 10 mg metoclopramide. Prolactin levels did neither differ basally nor after stimulation. Body weight and LH levels were correlated by r = 0.63. This correlation was not caused by different estradiol levels. A postulated influence of low body weight on catecholestrogen formation could not be inferred by effective change in dopamine metabolism.

Separation of subunits of pike eel gonadotropin by hydrophobic interaction chromatography

Subunits of pike eel gonadotropin were dissociated in propionic acid and separated by hydrophobic interaction chromatography on phenyl-Sepharose CL-4B with a high yield (79%). Isolated subunits were homogeneous, as tested by sodium dodecyl sulphate disc electrophoresis and by N-terminal analysis. The biological activities of two subunits, S-I and S-II, were 0% and 2.8% of native molecule, respectively, as assayed by stimulation of androgen production on carp testes. Reassociated molecules restored about 75% activity.

[Current diagnosis and therapy of gestational trophoblastic tumors: experience with 24 patients]

Observation of 24 gestational trophoblastic tumors, i.e. 20 hydatidiform moles, 1 invasive hydatidiform mole, 1 non-metastatic and 2 metastatic choriocarcinomas, is reported. The diagnoses were based on case record data, clinical findings, echography and radioimmunoassay of human gonadotropin (HCG). The therapy was oriented towards maintaining fertility in reproductive women. For treatment with cytostatic drugs the patients were allocated to a low risk and a high risk group according to history, diagnosis and former therapy, and an appropriate mono- or combined therapy was started. 17 of 24 patients were cured by surgery in an initial therapy phase. 7 tumors were progressive, 6 of which responded to secondary surgical or cytostatic treatment. One patient died from metastases of choriocarcinoma. The total cure rate of 96% was rendered possible by regular follow-up including bimanual palpation, echography, HCG-assay and chest X-rays.

Pituitary gonadotropin content and gonadosomatic index in Clarias batrachus a fresh water teleost

The pituitary gonadotropin content in Clarias batrachus was determined by radiophosphorus assay in chicks. The levels in spawning male, post spawning male, spawning female and post spawning female were found to be 65.66, 27.7, 36.69 and 49.98 micrograms LH activity/kg body weight respectively. The gonadosomatic index (GSI) in the above groups was found to be 0.3599, 0.0763, 9.2327 and 0.4334 respectively. Correlation between the gonadotropins and GSI was also worked out but was found to be statistically non-significant (P > 0.05).

Functional cytology of the pituitary gland of the teleost Clarias batrachus (L.)

The RPD (rostral pars distalis) is formed of two cell types. The erythrosinophilic acidophils were hypertrophied in response to ammonium sulphate treatment and dark background adaptation. The response to former may be due to osmoregulatory involvement. The PbH positive corticotrophs were markedly hypertrophied and degranulated in response to metopirone and ammonium sulphate treatments. They were moderately activated in the dark and white background adapted fish. The PPD (proximal pars distalis) is composed of two types of cyanophils and acidophils. The thyrotrophs are identified by their hypertrophic response to radiothyroidectomy and thiourea treatment. They are distributed in the ventral part of the PPD, posterior neurohypophysis and PI (pars intermedia). The gonadotrophs which largely occupy the dorsal aspect of the PPD increase numerically as the gonads mature and become the major cell type before spawning. The acidophilic somatotrophs are distributed all over the PPD. They are the predominant cell type in the PPD of fish with immature gonads. They gave strong reaction to Baker's acid haematein indicating the presence of phospholipid. Both PbH and PAS cells of PI were stimulated in fish kept in dark background whereas they did not exhibit any obvious change under white background adaptation.

Gonadotropin-like substance in the preimplanted rabbit blastocyst

The presence of a gonadotropin-like substance in preimplanted rabbit blastocyst fluid was determined bu radioreceptorassay of human chorionic gonadotropin (hCG)/luteinizing hormone (LH), using receptors prepared from bovine corpus luteum, rat testis, and rat ovaries. An average of 16.6 microliter of fluid containing 0.83 ng of luteotropic material was recovered from each blastocyst. An intense fluorescence was exhibited by the trophoblastic cells of the blastocysts treated with fluorescein-conjugated gamma-globulin isolated from antiserum raised against human chorionic gonadotropin. Serum concentrations of LH as well as estradiol, progesterone, and 17 alpha-hydroxyprogesterone up to day 6 after mating were determined in pregnant rabbits and compared with those in pseudopregnant and normal rabbits. In pregnant rabbits after mating, a surge of 62 +/- 15 ng of luteinizing hormone and 73 +/- 22 ng of progesterone/ml of serum occurred which returned to basal levels at 6 hours and on day 1, respectively. Secondary increases in serum luteinizing hormone of 26 +/- 12 to 36 +/- 16 ng/ml on days 3 and 5 and in serum progesterone of 16 +/- 4 and 14 +/- 5 ng/ml on days 5 and 6, respectively, were observed in pregnant rabbits.

[Gonadotropin from the bovine pineal body. Evidence of its similarity with the luteinizing hormone of the pituitary gland]

Gonadotropin affiliated by biological and immunochemical properties to the luteinizing hormone of the hypophysis was revealed in the purified extracts from the bovine pineal glands. Biological properties of gonadotropin from the pineal glands were assessed by the reactions specific of the luteinizing hormone. Immunochemical properties of gonadotropin were studied by means of gel-precipitation in agar gel, immunoelectrophoresis and radioimmunochemical analysis. It was found that the specific content of gonadotropin in the epiphysis was 80 times lower than the specific content of the luteinizing hormone in the hypophysis, but exceeded the LH concentration in the blood serum 555 times and in the cerebrospinal fluid 6.8 times. Immunoreactive LH was absent in the extracts of the brain cortex, the liver and the ovaries. A theoretical interpretation of a possible physiological role of the LH-like gonadotropin in the endocrine regulation of the reproductive function of the organism is given in this work.

Experimental demonstration of the cell types in the adenohypophysis of the gobiid fish, Rhinogobius brunneus

The hypophysis of the common freshwater goby, Rhinogobius brunneus, accompanying gonadal maturation, was studied light microscopically to determine the cell types by the aid of the administration of antithyroidal and antiadrenocortical drugs. It is peculiar in that the hypophysis is entirely buried in the hypothalamus, and that the entire adenohypophysis is covered with a thin layer of the neurohypophysis. Two types of cells, azocarminophil prolactin cells and PbH-positive adrenocorticotrophs, are discernible in the rostral pars distalis. The proximal pars distalis consists of three types of cells: weakly AF positive thyrotrophs, strongly AF positive gonadotrophs and orangenophil somatotrophs. In spite of the application of several stainings, only one cell type, the PbH-positive cell, is demonstrated in the pars intermedia.

Localization of gonadotrophic hormones in the dog pituitary gland. A study using immunoenzyme histochemistry and chemical staining

Using the immunoperoxidase technique and antisera to the specific beta (beta) subunits of FSH and LH1, selective immunochemical staining was localized mostly in the same cell type in the pars distalis and pars tuberalis of the dog pituitary gland. However, some cells were consistently shown to react solely with antisera to either LH beta of FSH beta. The cells stained for FSH beta were at least 1.5 times less numerous than those shown to contain LH beta. In the pars distalis of adult male dogs the immunoreactive gonadotrophs varied greatly in their relative proportion and were mostly shown to be much less numerous than in bitches in the anestrus phase of the sexual cycle. These cells were found to be positive to aldehyde fuchsin, alcian blue, periodic acid-Schiff (PAS) and aniline blue. The performic acid-alcian blue (pH 0.2)-PAS-orange G procedure stained the FSH/LH cells blue or turquoise, demonstrating TSH cells (blue-purple), ACTH/MSH cells (red-purple) and PRL cells (orange-red). The FSH/LH cells were further differentiated from other functional cell types of the pars distalis on the basis of their typical cytological features, intraglandular distribution and by immunochemical double staining. These observations support the concept that the one cell-one hormone theory may not apply to gonadotrophic hormones, although some cells seem to be the source of either FSH or LH.

Gonadotropin responses to luteinizing releasing factor in boys treated with cyclophosphamide for nephrotic syndrome

Cyclophosphamide therapy of the nephrotic syndrome has been associated with oligo- and azoospermia and with abnormalities of testicular histology in adults and pubertal boys. In 15 prepubertal boys, no abnormalities of basal serum levels of LH, FSH, or T were found when they were studied 8 months to 7 years after cyclophosphamide therapy. Five boys were pubertal during therapy were found to have elevated mean basal values of gonadotropins with normal testosterone levels and elevated LH responses to LRF; the FSH responses to LRF were elevated in four patients. One of four boys who were prepubertal during therapy but pubertal at the time of testing had an elevated basal LH and LH response to LRF. Three boys who were prepubertal at the times of therapy and testing had normal LH responses to LRF. The LRF test may provide a means of identifying the patient who has sustained testicular injury and who may require testicular biopsy.

Evidence for a gonadotropin from nonpregnant subjects that has physical, immunological, and biological similarities to human chorionic gonadotropin

Substances from urinary extracts of normal, nonpregnant subjects and human pituitary gonadotropin preparations were found to react similarly to human chorionic gonadotropin (hCG) in a radioimmunoassay system that is highly specific for hCG and without crossreactivity to human luteinizing hormone (hLH). The antiserum was produced in a rabbit immunized with a bovine albumin conjugate of the unique carboxyl-terminal peptide (residues 123-145) isolated from a tryptic digest of the reduced, S-carboxymethylated hCGbeta subunit. The antibody recognition site on the peptide was found to reside on the last 15 amino acid residues of the carboxyl-terminal peptide, as evidenced by the competitive binding activities against 125I-labeled hCG of a series of peptides chemically synthesized according to the carboxyl-terminal sequence of HCGbeta. In order to elucidate the nature of the crossreacting substance in urinary extracts, a human postmenopausal urinary preparation (Pergonal) and a kaolin-acetone extract of urine from a patient with Klinefelter's syndrome were subjected to gel chromatography on Sephadex G-100. The results indicate that fractions showing immunocrossreactivity with the antiserum to hCGbeta-carboxyl-terminal peptide coeluted with 125I-labeled hCG which was separated distinctly from hLH. The same fractions from this postmenopausal urinary gonadotropin preparation exhibited in vitro biological activity proportional to the immunocrossreactivity of the hCG-specific antiserum. Concentration of postmenopausal women's urine by acetone precipitation retained approximately five times more immunoreactivity per unit volume than kaolin-acetone extraction, when assayed with the antiserum to hCGbeta-carboxyl-terminal peptide.

[Mental anorexia: gonadotrophic response to clomifene citrate. Sixteen cases]

Sixteen patients with anorexia nervosa and secondary amenorrhoea received clomiphene citrate, eight before any other treatment (200 mg of clomiphene citrate per day for four days) and eight others after partial or total correction of weight loss (50 mg of clomiphene citrate per day for five days). Menstruation occurred in four patients of the second group. An elevation of plasma LH was demonstrated in 4 cases in the first group and 7 of the second group. Variation in FSH was not always parallel with LH. The authors discuss the physiopathological mechanism of gonadotrophic insufficiency in anorexia nervosa and define the role of clomiphene citrate in the treatment of this disorder.

[Heterogeneity of protein hormones in radioimmunoassay]

Radioimmunoassay measures antigenic determinants of hormonal molecules in the plasma and tissues. These estimations carried out after fractionation in biological fluids, have revealed several immunological forms of the same hormone. These immunoreactive forms may be added to already well known elements of hormonal heterogeneity: formation of aggregate, polymerisation, links to transport proteins, microheterogeneity by silent mutation. The main problem is in the relationship of the various immunoreactive forms to the same hormonal sequence. The similar immunoreactive forms of high molecular weight (big hormone) usually have low biological activity and suggest the presence of prohormone; the suggestion of prohormonal nature depends on the chronology of the incorporation of labelled leucine and enzymatic transformation of prohormone with low biological into active hormone. The forms with high molecular weight and similar immunological activity may be of another nature. Thus, it has been shown that the biosynthetic nature of a compound such as big big insulin in the rat is doubtful owing to the absence of specific incorporation of labelled leucine into the immunoprecipitate of this fraction. The significance of low molecular weight forms is still little known. There may be breakdown products, biologically active products or biosynthetic products. An example of these forms is supplied by the existence of an alpha sub-unit of gonadotrophin present in the plasma of menopausal women. The interest of analytical methods by radio-receptor, stimulation of cyclase activity in the identification of biological activity of immunoreactive forms, is discussed in relation to immunological forms of enteroglucagon. An unusual aspect of the evolutive and adaptative character of hormonal heterogeneity is given by the gastro-intestinal hormones: secretin, vasoactive intestinal polypeptide and enteroglucagon, have similar structure and mode of action; however, the existence of a specific receptor is a sign of their functional differentiation at molecular level.

A testosterone-secreting, gonadotropin-responsive pure thecoma and polycystic ovarian disease

A 31-yr-old hirsute female with oligoamenorrhea since menarche had markedly elevated peripheral plasma testosterone (T) concentrations of 250-255 ng/100 ml (normal 20-60 ng/100 ml), which lacked a diurnal rhythm, were not suppressed by dexamethasone, were decreased by ACTH, and were massively increased to 2,530 ng/100 ml by human chorionic gonadotropin (hCG). The binding capacity of T-binding globulin (TeBG) was 0.2 mug/100 ml (normal = 1.1-3.3 mug/100 ml). Plasma delta 4-androstenedione (A) was elevated at 374-681 ng/100 ml (normal = 90-135 ng/100 ml). Plasma estrone (E1) and estradiol (E2) were normal. The endometrium was proliferative. A T-secreting tumor was suspected because the plasma T levels were higher than those observed in polycystic ovarian disease. Exploratory surgery revealed bilateral polycystic ovaries and a pure thecoma in the right ovary which was not visible on surface examination. The thecoma did not contain granulosa cells. Plasma T in the right ovarian vein, draining the tumor, was 28,200 ng/100 ml and in the left ovarian vein was 2,600 ng/100 ml. Plasma A was elevated in both ovarian veins: 11,170 ng/100 ml on the left and 8,360 ng/100 ml on the right. The thecoma contained 1.35 mug/g of T and only 0.014 mug/g and 0.007 mug/g of E2 and E1, respectively. Plasma A and T after bilateral oophorectomy and removal of the thecoma were normal at 184 ng/100 ml and 40 ng/100 ml, respectively.

CONCLUSIONS

1) This pure thecoma produced primarily T rather than E1 OR E2 and was gonadotropin-responsive. 2) A very high plasma androgen level in a female is an important clue to the presence of a tumor. A T-secreting tumor should be ssupected when the peripheral plasma T is over 250 ng/100 ml and when plasma T increases to over 1,000 ng/100 ml following hCG stimulation. 3) Tumors cannot be classified as estrogenic or androgenic on the basis of the character of the endometrium.

A new method simplifying collection of serial specimens for gonadotropin determinations

Patterns of gonadotropin levels have been compared in specimens of serum, 24-h urine collections, and first morning urine voidings collected throughout a menstrual cycle from 8 sexually mature, young women. Quantities of gonadotropins in first morning voidings were found to provide a reliable estimate of 24-h excretion of these hormones and demonstrate the same patterns of change as do serum and 24-h urine specimens. Thus first morning voidings satisfactorily overcome logistical problems inherent is serial serum and 24-h urine sampling for studying gonadotropin excretion patterns.

[Effect of gamma globulin on reactivity of the organism. V. Types of biological activity of gamma globulin preparations]

Biological activity of 110 series of commercial gamma-globulin preparations was studied; they were found to contain placental antigens, group-specific blood substances, gonadotropic hormones and antibodies to them. Placental antigens were found in 12% of placental and abortive gamma-globulin batches in titres of 1 : 2--1 : 16; no placental protein was revealed in donor gamma-globulin. There were group-specific blood substances in all the batches of placental and abortive gamma-globulin studied (in titres of 1 : 138--A, 1 : 112 B in the placental gamma-globulin and in titres of 1 : 48.9--A, 1 : 32--B in the abortive gamma-globulin). In the preparations from the venous blood group-specific substances were either absent or present in lowe titres only (1 : 2). The value of gonadotropic hormones in the placental gamma-globulin batches constituted 873+/-157, and in the abortive--991.4+/-147 IU/l; no gonadotropins were revealed in donor gamma-globulin. The mean titres of antibodies to gonadotropin hormone in the gamma-globulin preparations made of placental blood constituted 1 : 236+/-32, of abortive--1 : 131+/-16.6, and of the venous blood--1 : 46+/-24.7. The presence of biologically-active substances in the gamma-globulin preparations pointed to the necessity of increased requirement of their quality; additional requirements to its standardization proved to be also necessary.

An in vitro bioassay for a mulluscan gonadotropin

1. Protein synthesis occurs at a high rate in the ovaries of maturing Octopus vulgaris and can be measured from the incorporation of [14C]leucine in vivo and in isolated groups of eggs in vitro. 2. Removal of the optic glands in vivo 1--3 days prior to testing markedly reduces amino acid incorporation in vivo or in vitro. After 5 days in vivo incorporation stops. 3. The rate of incorporation in vitro is increased by the addition of optic gland extract. 4. Analysis of the kinetics of leucine uptake and incorporation in vitro indicates that the hormone has an effect on the inward transport of leucine which is independent of its action on protein synthesis. 5. Electron-microscope studies of the follicle cells and ova show that the former are the site of protein synthesis. 6. Changes in either uptake or incorporation into protein by the follicle cells can be used as a qualitative biolobical assay for the optic gland hormone. Uptake is very easy to measure but incorporation is the more sensitive parameter. Either is potentially suitable as a quantitative assay for this and perhaps also for other molluscan gonadotropins.