SOME FACTORS AFFECTING THE RESPONSE OF THE IMMATURE MOUSE TO PREGNANT MARE SERUM GONADOTROPHIN AND HUMAN CHORIONIC GONADOTROPHIN

1966 ◽  
Vol 34 (1) ◽  
pp. 41-50 ◽  
Author(s):  
D. R. LANG ◽  
D. R. LAMOND
Keyword(s):  
Dose Response ◽  
Time Of Day ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Uterine Weight ◽  
Restricted Diet ◽  
Factors Affecting ◽  
Immature Mouse ◽  
Pregnant Mare Serum Gonadotrophin

SUMMARY Deprivation of food for 24–48 hr. before the injection of gonadotrophin into mice reduced mean uterine weights and the slopes of the dose-response lines; the effect was greater with human chorionic gonadotrophin (HCG) than with pregnant mare serum gonadotrophin. Age and time of weaning relative to the injection of gonadotrophin, and the number of experimental mice per cage, also affected the uterine weight response. Age and weight influenced the number of ovulations after injections of HCG. Fasting for 48 hr. before the priming injection reduced numbers of ovulations as compared with a restricted diet or fasting for 48 hr. after priming. The time of day of the priming and ovulatory injections influenced the number of ovulations, injections in the afternoon resulting in more ova than injections in the morning.

scholarly journals Effects of infantile thymectomy on ovarian functions and gonadotrophin-induced ovulation in prepubertal mice: role of thymulin

2000 ◽  
Vol 166 (2) ◽  
pp. 381-387 ◽  
Author(s):  
L Garcia ◽  
L Hinojosa ◽  
R Dominguez ◽  
R Chavira ◽  
P Rosas
Keyword(s):  
Ovarian Development ◽  
Neonatal Period ◽  
Ovarian Response ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Uterine Weight ◽  
Sequential Injection ◽  
And Function ◽  
Pregnant Mare Serum Gonadotrophin

The effects of thymectomy performed on 10-day-old (Tx-10) mice on spontaneous puberty and the ovulatory response induced by gonadotrophin treatment were analysed, together with the effects of thymulin replacement from 10 days of age. Infantile thymectomy induced a delay of puberty, a decrease in serum 17beta-oestradiol concentration and a reduced total number of follicles. Injection of thymulin (12 ng/g body weight) to Tx-10 mice resulted in an earlier onset of puberty, a decrease in the weights of ovaries and uterus, and an increase in serum 17beta-oestradiol concentrations. In control and Tx-10 mice, treatment with pregnant mare serum gonadotrophin (PMSG) (5 IU) at 25 days of age resulted in ovulation and the numbers of ova shed by ovulating animals were similar. When the animals were injected with 1 IU PMSG ovulation did not occur. In Tx-10 mice, both 1 and 5 IU PMSG increased the number of follicles to values similar to those observed in the controls. In Tx-10 mice the sequential injection of PMSG (1 IU) and human chorionic gonadotrophin (hCG) (3 IU) resulted in ovulation, but the number of ova shed was lower than in controls. When these animals were injected daily with thymulin, an increase in the number of ova shed and serum 17beta-oestradiol concentrations was observed. The uterine weight of Tx-10 mice was always significantly reduced in response to gonadotrophin treatment. Thymulin injection in PMSG-hCG-treated Tx-10 mice provoked a significant increase in uterine weight. The results suggest that the presence of the thymus after the neonatal period is necessary to normal ovarian development and function. The increase in gonadotrophin-induced ovarian response produced by thymulin replacement indicates that this peptide has a role in this process as one of the connecting signals between thymus and ovaries.

AUGMENTATION BY CHLORMADINONE OF THE UTERINE WEIGHT RESPONSE TO HUMAN CHORIONIC GONADOTROPHIN IN INTACT IMMATURE RATS

1965 ◽  
Vol 33 (3) ◽  
pp. 447-454
Author(s):  
M. J. K. HARPER
Keyword(s):  
Single Injection ◽  
Direct Action ◽  
Follicular Development ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Uterine Weight ◽  
Control Value ◽  
Orally Active ◽  
Stimulation Of

SUMMARY Administration of chlormadinone, an orally active progestational agent without significant oestrogenic activity, to intact immature female rats did not affect either ovarian or uterine weight significantly compared with controls. A single injection of human chorionic gonadotrophin (HCG) caused a 73 % increase in uterine weight in 24 hr. over the control value. This dose significantly increased ovarian weight and although it caused some stimulation of follicular development, ovulation during this time did not occur. When animals were treated with chlormadinone for 8 days, and received HCG on the 8th day, uterine weight was 170% greater than in the controls and 56% greater than with HCG alone. The uterine weight produced was similar to that found in animals treated with mestranol, a potent oestrogen, and HCG. In ovariectomized animals HCG did not affect uterine weight, while the small increase produced by chlormadinone was unaltered when HCG also was given. Mechanisms are discussed by which this augmentation of the uterine response to HCG might be produced. It seems most likely that chlormadinone administration causes storage of endogenous gonadotrophin in the pituitary, and that the exogenous gonadotrophin acts as the 'trigger' for the release of stored hormone, probably by a direct action on the hypothalamus.

Internalization of receptor-bound human chorionic gonadotrophin in preovulatory rat granulosa cells in vivo

1983 ◽  
Vol 103 (3) ◽  
pp. 406-412 ◽  
Author(s):  
Kalle Jääkeläinen ◽  
Seppo Markkanen ◽  
Hannu Rajaniemi
Keyword(s):  
Plasma Membrane ◽  
Granulosa Cells ◽  
Subcellular Distribution ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Female Rats ◽  
Electron Microscope Autoradiography ◽  
Silver Grains ◽  
Pregnant Mare Serum Gonadotrophin

Abstract. The subcellular distribution of 125I-labelled human chorionic gonadotrophin (hCG) in preovulatory rat granulosa cells was studied in vivo. Pregnant mare serum gonadotrophin-pretreated immature female rats received an iv injection of [125I]hCG a few hours before the endogenous preovulatory gonadotrophin surge. The animals were killed at 2 or 6 h after the [125I]hCG injections. Light microscope autoradiographs showed that the mural granulosa cells of large follicles were the most highly labelled cells in the ovaries. Electron microscope autoradiography was used to study the subcellular distribution of radioactivity in the mural granulosa cells. At 2 h 45% of the counted silver grains were associated with the plasma membrane and 10% with the lysosomes, at 6 h the values were 51% and 9%, respectively. The distribution of the observed silver grains was compared with the generated expected source to grain pairs by computerized linear multiple regression analysis. The magnitudes of the regression coefficients revealed that the plasma membrane and the lysosomes were the only specifically 125I-labelled organelles, that a few radioactive molecules were located diffusely over the cytoplasm at 2 h and that the 125I-radioactivity of the nuclei was negligible. The present results suggest that preovulatory rat granulosa cells are in vivo able to internalize into lysosomes [125I]hCG initially bound to LH/hCG receptors of the plasma membrane.

Effects of thymulin on spontaneous puberty and gonadotrophin-induced ovulation in prepubertal normal and hypothymic mice

1999 ◽  
Vol 163 (2) ◽  
pp. 255-260 ◽  
Author(s):  
L Hinojosa ◽  
R Chavira ◽  
R Dominguez ◽  
P Rosas
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Vaginal Opening ◽  
Serum Progesterone ◽  
Thymic Hormone ◽  
Induced Ovulation ◽  
Gonadotrophin Secretion ◽  
Age Dependent ◽  
Neuroendocrine Mechanisms ◽  
Pregnant Mare Serum Gonadotrophin

The effects of thymulin administration beginning on days 19 or 24 of age on spontaneous puberty and gonadotrophin-induced ovulation were analysed in female normal and hypothymic mice. In normal and hypothymic mice, the daily administration of thymulin at 24 days of age resulted in a delay in the age of vaginal opening, with an increase in serum progesterone levels. Normal mice treated with 200 ng thymulin beginning on day 19 of age and injected with pregnant mare serum gonadotrophin (PMSG) 24 h later had an increase in ovulation rate, number of ova shed and weight of the ovaries. None of the hypothymic mice treated with thymulin on day 19 and PMSG on day 20 ovulated. PMSG treatment on day 25 induced ovulation in hypothymic mice. When these animals were injected previously with 200 ng thymulin, the number of ova shed by ovulating animals was lower than in PMSG-treated animals. Administration of thymulin and sequential injection of PMSG and human chorionic gonadotrophin 54 h later resulted in an increase in ovulatory response in comparison with those receiving only PMSG. The results suggest that thymulin plays a role in the regulation of spontaneous puberty through its effects on adrenal and ovarian endocrine functions. The increase in the ovarian PMSG response-treated animals, previously given thymulin, showed that this thymic hormone participates in the regulation of gonadotrophin secretion mechanisms and seems to be dose- and age-dependent. In hypothymic mice, neuroendocrine mechanisms regulating puberty are different from those of normal mice.

CONCENTRATIONS OF CYCLIC AMP IN RABBIT OVARIAN TISSUE DURING THE PREOVULATORY PERIOD AND PSEUDOPREGNANCY AFTER INDUCTION OF OVULATION BY ADMINISTRATION OF HUMAN CHORIONIC GONADOTROPHIN

1975 ◽  
Vol 65 (1) ◽  
pp. 73-82 ◽  
Author(s):  
A. K. GOFF ◽  
PATRICIA W. MAJOR
Keyword(s):  
Cyclic Amp ◽  
Dose Response ◽  
Ovarian Tissue ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Corpora Lutea ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Induction Of Ovulation ◽  
Relationship Of

SUMMARY Concentrations of cyclic AMP were measured in rabbit ovaries at various times after injection of an ovulatory dose of human chorionic gonadotrophin (HCG). A biphasic increase in cyclic AMP concentration occurred during the preovulatory period, with peaks 30 min and 3–4 h after HCG injection. Concentrations of cyclic AMP had returned to those observed in ovaries of control oestrous animals before the onset of ovulation 10–12 h after administration of HCG, and remained low throughout the period of pseudopregnancy. Concentrations of cyclic AMP in the newly formed and developing corpora lutea were similar to the concentrations observed in the remainder of the tissue during this period. No significant increase in cyclic AMP concentration was observed 7–9 days after initiation of ovulation. Concentrations of ATP were also investigated during the preovulatory period. The dose– response relationship of HCG to cyclic AMP production in oestrous rabbit ovaries was investigated.

STIMULATION BY β2-ADRENERGIC RECEPTORS OF THE PRODUCTION OF CYCLIC AMP AND PROGESTERONE IN RAT OVARIAN TISSUE

1980 ◽  
Vol 87 (1) ◽  
pp. 123-129 ◽  
Author(s):  
ALBERT RATNER ◽  
G. K. WEISS ◽  
CAROLYN R. SANBORN
Keyword(s):  
Cyclic Amp ◽  
Adrenergic Receptors ◽  
Ovarian Tissue ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Adrenergic Stimulation ◽  
Immature Rats ◽  
Luteal Tissue ◽  
Pregnant Mare Serum Gonadotrophin ◽  
Stimulation Of

Ovarian tissue from immature rats treated with pregnant mare serum gonadotrophin (PMSG) or PMSG and human chorionic gonadotrophin was incubated in Medium 199. Stimulation of the formation of cyclic AMP in follicular and luteal tissue by terbutaline (10−5 mol/l), a selective β2-agonist, was blocked by butoxamine (10−5 mol/l), a selective β2-antagonist, whereas practolol (10−5 mol/l), a selective β1-antagonist, was ineffective. Propranolol (10−5 mol/l), a non-selective β-antagonist, butoxamine nor practolol affected the increase in cyclic AMP promoted by the addition of 1 μg LH. Stimulation of the production of progesterone in both follicular and luteal tissue by terbutaline was blocked by butoxamine, but not by practolol. These findings indicated that β-adrenergic stimulation of ovarian cyclic AMP and progesterone is mediated by β2-adrenergic receptors.

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.

AUGMENTATION OF THE RAT UTERINE WEIGHT RESPONSE TO HUMAN CHORIONIC GONADOTROPHIN BY VARIOUS STEROIDS

1974 ◽  
Vol 75 (1) ◽  
pp. 141-147 ◽  
Author(s):  
L. J. Hipkin
Keyword(s):  
Dose Level ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Uterine Weight ◽  
Ovarian Weight ◽  
Gonadotrophin Secretion

ABSTRACT Dehydroepiandrosterone (DHA) augments the activity of human chorionic gonadotrophin (HCG) in the rat by increasing endogenous pituitary gonadotrophin secretion. The following experiments were undertaken to investigate the mechanism underlying this effect. Androstenedione (40 μg), dihydrotestosterone (200 μg) and testosterone (200 μg) augmented the rat uterine weight response to 0.5 IU of HCG. At these doses, the steroids did not affect basal uterine weight although this was increased when 1 mg of a steroid was injected. Androsterone (1 mg), 17α-hydroxypregnenolone (1 mg) and progesterone (200 μg) neither augmented HCG activity nor increased basal uterine weight. Ovarian weight differences were not significant in any of the experiments. Androstenedione, DHA, dihydrotestosterone and testosterone (200 μg dose level) did not significantly affect the uterine weight of castrated animals, and responses to 0.04 μg of oestradiol were not potentiated. The results with androstenedione, dihydrotestosterone and testosterone are identical to those obtained with DHA and suggest that these steroids may also increase pituitary gonadotrophin secretion.

STUDIES ON THE TETRAZOLIUM REDUCTION ASSAY FOR FOLLICLE-STIMULATING HORMONE

1970 ◽  
Vol 65 (3) ◽  
pp. 459-465
Author(s):  
E. T. Bell ◽  
D. W. Christie
Keyword(s):  
Follicle Stimulating Hormone ◽  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Triphenyltetrazolium Chloride ◽  
Reduction Assay ◽  
Immature Mouse ◽  
Consistent Increase ◽  
Tetrazolium Reduction ◽  
Stimulating Hormone

ABSTRACT The technique of Casellato et al. (1967) for the bioassay of follicle-stimulating hormone (FSH) involving the reduction of 2,3,5-triphenyltetrazolium chloride in the vagina of the immature mouse following the administration of FSH and human chorionic gonadotrophin (HCG) has been studied. In initial experiments it was found that FSH administration did not cause a consistent increase in tetrazolium reduction. Accordingly, modifications to the method involving the dosage of HCG, the time of tetrazolium injection and the time of autopsy after tetrazolium administration have been studied. It was concluded that in the mouse colony employed the tetrazolium assay could not be established.

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