bluuebunny/crossref_metadata_2025_split huggingface dataset:
OVULATION INHIBITION WITH HUMAN CHORIONIC GONADOTROPHIN
Authors: Friedrich F. , Kemeter P. , Salzer H. , Breitenecker G. 
Published: December 2008

ABSTRACT
Eight women with regular menstrual cycles were treated daily during 9 cycles with HCG (Human Chorionic Gonadotrophin) 3000 or 5000 IU daily for a period of 4–7 days. This treatment was started between the 1st and the 6th day after the onset of menstruation. Control of the treatment cycles was performed by basal body temperature, pregnanediol serial estimations, endometrial biopsies and in addition in 5 treatment cycles by radio-immunological assay of oestradiol-17β (Oe2), progesterone, LH and FSH from the serum at intervals of 1 to 3 days. In 6 of these cycles where treatment started on the 4th day or later, ovulation was inhibited (2 cycles) or postponed (4 cycles) to the 24th–46th day. In these 6 treatment cycles the progesterone and pregnanediol increase during HCG treatment was poor or absent. The typical Oe2 increase of the normal menstrual cycle was impaired. In the 3 remaining cycles where treatment was started on the 1st, 2nd and 4th day, we observed during HCG treatment increases in Oe2 and progesterone serum values similar to that found during corpus luteum activity, and menstruation from a secretory endometrium between the 13th–19th day of the cycle. The histologically examined ovaries of one woman who was treated with HCG from the 2nd to the 6th day of the cycle showed distinct Iuteinization of the theca interna of all tertiary follicles and a beginning degeneration of the granulosa. These findings give support to the hypothesis that the luteinization of the theca interna leads to degeneration of the tertiary follicles thereby causing ovulation inhibition or postponement of ovulation.
EFFECT OF INDOMETHACIN, AN INHIBITOR OF PROSTAGLANDIN BIOSYNTHESIS ON THE LENGTH OF PSEUDOPREGNANCY IN RATS AND HAMSTERS
Authors: Lau I. F. , Saksena S. K. , Chang M. C. 
Published: December 2008

ABSTRACT
Pseudopregnancy (PSP) in rats was significantly lengthened after subcutaneous administration of 0.2–1.0 mg indomethacin/day, starting on day 5 of PSP. Injections of 1 mg indomethacin on days 5 and 6 or days 7 and 8, as well as a single injection of 2 mg indomethacin on day 6, also produced a significant increase of the duration of PSP. In hamsters, doses of 300–500 μg indomethacin per day starting on day 5 of PSP did not alter the length of PSP, but a significant prolongation varying from 11 to more than 30 days was observed after a treatment with 1 mg of indomethacin daily. It was further observed that the ovaries of hamsters autopsied on day 31 of PSP were very small and the uteri resembled those of ovariectomized animals. It is concluded that indomethacin lengthens pseudopregnancy in both rats and hamsters and that the latter species showed a more variable response. It seems that chronic administration of indomethacin in hamsters caused a long-lasting suppression of ovarian hormone production.
CHANGES IN LABELLING OF RIBONUCLEIC ACID SPECIES FRACTIONATED FROM THE RAT VENTRAL PROSTATE IN RESPONSE TO TESTOSTERONE
Authors: Isotalo Anja , Santti R. S. 
Published: December 2008

ABSTRACT
The total RNA isolated at various times up to 24 h after testosterone administration from the ventral prostate of castrated rats, was labelled either by injecting 3H-orotic acid directly into the ventral prostate 6 h before the animals were killed, or by incubating prostatic tissue in vitro with 3H-uridine for 20 to 60 min. The isolated RNA was separated into tRNA, ribosomal RNA (Q1 RNA) and two DNA-like RNA fractions (Q2) and TD RNA) by chromatography on methylated albumin kieselguhr (MAK) columns, and the fractions were further analysed by sucrose gradient centrifugation.
Testosterone given into castrated animals for 12 h, stimulated the labelling of all main fractions. The radioactivity of TD RNA after a 60-min incubation period in vitro with 3H-uridine was approximately twice that seen in the castrated rat, while there was a 3.1- and 2.2-fold increase in the radioactivity of the Q1 and Q2 RNA fractions respectively. Kinetics of incorporation of 3H-uridine into different RNA fractions revealed that the hormone facilitated the labelling of the TD RNA fraction relatively more than that of the Q2 fraction. The injection of 3H-orotic acid into the ventral prostate labelled the Q1 RNA preferentially. More than 60 % of the recovered radioactivity was found in Q1 RNA (as 18 and 28 S). Testosterone increased markedly (9.4-fold) the labelling of this fraction. It was concluded that testosterone has an activatory effect on the production of ribosomal RNA, and the bulk of the testosterone effect on the total RNA labelling is to be found in this fraction. Furthermore, it seems likely that testosterone also stimulates both the synthesis and processing of DNA-like RNA.
When actinomycin D was given 2 h before the hormone administration in a dose of 25 μg per 100 g of body weight, there was no noticeable increase in the labelling of any fraction above the level seen in the untreated castrated rat. There is evidence that testosterone exerts some effects on the labelling of proteins with radioactive amino acids and 14C-glucose metabolism in the absence of that fraction of the total RNA synthesis which is sensitive to a low dose (25 μg per 100 g of body weight) of actinomycin D (Isotalo & Santti 1972). In this way it may be concluded that the major changes of the RNA synthesis after testosterone administration are likely to be secondary to the protein synthesis and glucose metabolism, or the hormone exerts its anabolic effect on prostatic cells at different sites and by different modes of action, each of which can be operated independently.
THE RELATIVE ROLES OF IODINATION AND IODOTHYRONINE CONTENT ON THYROGLOBULIN STABILITY
Authors: Fukuda Hitoshi , Greer Monte A. 
Published: December 2008

ABSTRACT
We have independently varied the degree of iodination and of iodothyronine formation over a wide range by acutely administering various doses of perchlorate and/or methimazole to severely iodine-deficient rats 30 min before giving 131I− with graded quantities (1–100 μg of 127I−). Thyroids were removed 4 h later and the soluble protein analyzed for labelled iodoamino acid composition and with sucrose density gradient ultracentrifugation. Since the total thyroid iodine content before administering 127I− was less than 1 μg, calculation of the degree of iodination and iodothyronine content of the labelled Tgb could be made from the known specificity of the injected labelled iodide. Newly organified iodine ranged from < 0.1 to 1.4 μg/thyroid and labelled iodothyronines from < 5 to 962 pmoles/thyroid. Both the degree of iodination and iodothyronine content varied directly with Tgb stability in the absence of inhibitors. But when Tgb iodination was kept constant, Tgb stability at pH 10.1 varied directly with iodothyronine content. When iodothyronine content was kept constant, Tgb stability was independent of the degree of iodination. Correlation of stability with iodothyronine content was highly significant (r = 0.79, P < 0.001) but not of stability with iodine content (r = 0.49, P > 0.05). We conclude that the primary determinant of Tgb stability in mild alkali is the iodothyronine content and not the degree of iodination of the protein. The increased Tgb stability may be induced by coupling between iodotyrosil residues of different 12 S subunits rather than between residues of the same 12 S subunit.
THE DIAGNOSTIC VALUE OF A RADIOIMMUNOASSAY FOR PARATHYROID HORMONE IN HUMAN SERUM
Authors: Almqvist Sven , Hjern Bo , Wästhed Birgitta 
Published: December 2008

ABSTRACT
A radioimmunoassay for the measurement of immunoreactive parathyroid hormone (PTH) in human serum is described. The assay is based on the ability of human parathyroid hormone (h-PTH) to compete with 125I-labelled bovine parathyroid hormone (b-PTH) for binding to a guinea-pig antiserum directed against b-PTH. The linear part of the standard curve was parallel with dose response curves for anti-b-PTH serum reacting with dilutions of sera from patients with primary hyperparathyroidism and from h-PTH purified from human parathyroid adenomas, indicating that levels of immunoreactive PTH could be expressed as b-PTH equivalents. The range in 62 healthy blood donors was 1.1–2.5 ng b-PTH Eq./ml. The reproducibility was satisfactory, and the sensitivity permitted the measurement of PTH concentrations down to 0.8 ng b-PTH Eq./ml. No cross-reaction with h-CT, h-STH or h-ACTH was observed.
The clinical value of the assay has been considered in a number of patients with various disorders of calcium metabolism, diagnosed and treated conventionally. About 80 per cent of patients with primary hyperparathyroidism had elevated PTH levels on one or more occasions before surgery. In patients with chronic renal failure of other aetiology than primary hyperparathyroidism the levels were usually far higher. Patients with primary hyperparathyroidism and increased S-creatinine had higher PTH levels than those with normal S-creatinine. After parathyroidectomy all previously increased PTH levels became normal or low. High PTH concentrations were found in 3 patients with normocalcaemic hyperparathyroidism who at operation were shown to have parathyroid adenomas. However, in normocalcaemic patients there were also some falsely elevated PTH values which limit the diagnostic value of the assay in this group of patients. Low PTH values were observed in patients with hypercalcaemia due to malignant disorders, indicating that PTH determination may be of some value in the diagnosis of patients with hypercalcaemia of unknown origin.
REGULATION OF PLASMA OESTROGENS IN NORMAL ADULT MALES
Authors: Doerr Peter , Pirke Karl M. 
Published: December 2008

ABSTRACT
The response of plasma oestradiol (Oe2), oestrone (Oe1), testosterone (T) and cortisol to dexamethasone and ACTH administration in normal adult males was ascertained. After an oral dose of 1.5 mg dexamethasone Oe1 decreased from 2.51 to 1.85 ng/100 ml (74 % of the control level, mean of 15 subjects) over night and after continuing the dexamethasone administration for two more days (twice daily 1.5 mg) Oe1 decreased to 1.30 ng/100 ml (52 %). Oe2 (control level 1.71 ng/100 ml) and T (678 ng/100 ml) did not change over night, but at the end of the test Oe2 decreased to 84 % and T to 91 % of the control level.
After a single im injection of 2 mg β 1–24 cortrophin Oe1 increased 1.9 times (mean of 13 subjects) without further increase during two more days of treatment (twice daily 1 mg), while Oe2 did not change over night and decreased to 75 % of the control level at the end of the test. Under ACTH T decreased to 66% of the control level over night and to 50% at the end of the test indicating a suppression of the testicular hormone secretion. From these results and those reported previously it was concluded that the testicular hormone secretion influences mainly Oe2 in peripheral plasma, while Oe1 depends mainly on the adrenal hormone secretion.
BLOOD PLASMA LEVELS OF PROGESTERONE AND OESTRADIOL IN THE DOG DURING THE OESTROUS CYCLE AND PREGNANCY
Authors: Edqvist L.-E. , Johansson E. D. B. , Kasström H. , Olsson S.-E. , Richkind M. 
Published: December 2008

ABSTRACT
Plasma oestradiol and progesterone levels were studied in German Shepherd and Greyhound bitches during the normal oestrous cycle, pregnancy and at parturition.
The mean oestradiol level increased from approximately 7 to 13 pg/ml during the fifth week before onset of oestrus. Oestradiol stayed at this level until pro oestrus which was characterized by a steady increase to a mean peak level of about 30 pg/ml 5–6 days before oestrus. At the start of oestrus the level was approximately 12 pg/ml. A level between 10–15 pg/ml was kept during the following 10 weeks whether or not the bitch was pregnant and no change occurred at parturition.
The mean progesterone level was found to be very low, around or under 1 ng/ml, until 1–4 days after the oestradiol peak after which the level gradually increased to around 10 ng/ml at the start of oestrus. During oestrus and metoestrus or pregnancy the pattern was inconsistent. In some bitches the level gradually increased during 3–4 weeks and reached a peak value of 30–50 ng/ml. The level then gradually decreased during 5–6 weeks. During the first 5 weeks of the same period progesterone in other bitches fluctuated between similar maximum levels and extremely low levels. After the fifth week the pattern was the same for all bitches. In the pregnant bitches there was a significant drop of the progesterone level at parturition.
The data suggest that the dog is not an ideal test animal for steroids synthetized for use in man.
SIMULTANEOUS DETERMINATIONS OF OESTRADIOL-17β, PROGESTERONE AND LUTEINIZING HORMONE IN THE PLASMA DURING THE OVULATORY CYCLE OF THE HEN
Authors: Shodono Masahide , Nakamura Takao , Tanabe Yuichi , Wakabayashi Katsumi 
Published: December 2008

ABSTRACT
Simultaneous determinations of plasma levels of oestradiol-17β, progesterone and luteinizing hormone (LH) during the ovulatory cycles of hens were performed using radioimmunoassay techniques without chromatography. Blood samples were collected from the wing vein of 7 hens with regular ovulatory cycle at intervals of 1, 2 or 4 h throughout 36 h starting 24–25 h before the second egg (C2) ovulation of the clutch and ending 11–12 h after C2 ovulation. The oestradiol-17β level of the plasma during the ovulatory cycle varied from 50 pg/ml to 250 pg/ml. The value was high 24 h before ovulation and decreased until 10 h before ovulation, then increased and reached a peak 4–5 h before ovulation, when it started to decrease again until 12 h after ovulation. The plasma levels of progesterone varied from 1 ng/ml to 6 ng/ml, and reached a peak 4–6 h before ovulation. The plasma LH value varied from 1 ng/ml to 4 ng/ml, and the changes in the levels corresponded well with that of progesterone, also showing a coincident peak.
PROGESTERONE-BINDING PROTEINS FROM ENDOMETRIUM AND MYOMETRIUM OF SHEEP UTERUS: A COMPARATIVE STUDY
Authors: Kontula Kimmo 
Published: December 2008

ABSTRACT
The binding of tritiated progesterone to the cytoplasmic progestogen receptors from oestrogen-primed sheep endometrium and myometrium has been investigated. The binding characteristics of the progesterone receptors from both sources were determined in the supernatant fractions obtained after high speed centrifugation of the myometrial and endometrial homogenates.
High affinity binding proteins with identical association constants for progesterone (1 × 109 m−1) were detected in both endometrium and myometrium. The concentration of binding sites was also of the same order of magnitude in both tissues. After centrifugation on sucrose gradients, these binding proteins were shown to have similar sedimentation constants, 7 S in a gradient containing no added KC1 and 4 S in a gradient containing 0.4 m KCI. The binding peaks from both sources could be abolished by heating the cytosol at 60°C for half an hour. The proteinaceous nature of the binding materials was demonstrated by incubation of the endometrial and myometrial cytosols with pronase, DNase and RNase: the binding was totally eliminated by the proteolytic action of pronase whereas DNase and RNase had no effect.
The ligand specificity of the two progesterone binding proteins was studied using a competitive protein-binding technique. Both the endometrial and the myometrial receptor proteins were shown to bind only steroids which are known potent progestogens. In addition, the relative affinities of the binding proteins for 37 steroidal compounds closely resembled each other. Thus, the physicochemical and binding data obtained show that a very close similarity exists between the progesterone-binding proteins in the endometrium and myometrium of ovariectomized sheep after oestradiol treatment.
THE HYPERCALCAEMIC SYNDROME IN RATS BEARING THE WALKER CARCINOSARCOMA 256
Authors: Minne H. , Raue F. , Bellwinkel S. , Ziegler R. 
Published: December 2008

ABSTRACT
The strain of Walker carcinosarcoma 256 described induces hypercalcaemia, hyperphosphataemia and hyperuraemia in tumour bearing rats. Changes in calcium and phosphorus excretion are observed as well as accompanying calcification of soft tissue organs and loss of bone calcium. These changes in calcium metabolism disappear after removal of the tumour, so that long-range action of the tumour can be stated. The results are discussed in comparison with three other animal models of tumour dependent hypercalcaemia.
DIAGNOSTIC VALUE OF THE LH-RELEASING HORMONE STIMULATION TEST IN FUNCTIONAL AMENORRHEA
Authors: Vandekerckhove D. , Dhont M. , Van Eyck J. 
Published: December 2008

ABSTRACT
LH-releasing hormone (25 μg, iv.) was administered to 37 women with functional amenorrhea. In addition to the clinical classification, these patients were divided into three groups according to the basal level of serum LH. A significant correlation was found between the base-line levels of LH and the serum concentration of oestradiol plus oestrone. The absolute increment of LH after the injection of LH-RH was found to be dependent only on the base-line level of LH. Except for the patients with anorexia nervosa, the base-line levels and the response pattern of FSH were almost the same for all three groups.
From the results of this study, it was concluded that:
The circulating levels of oestradiol and oestrone, where derived from ovarian secretion, actually depend on the gonadotrophic stimulus. In patients with functional amenorrhea, the oestrogens do not make an independent contribution to the pituitary response to LH-RH. Dysregulation of releasing hormones, whether located at the hypothalamic or suprahypothalamic level, necessarily influences the secretory capacity of the pituitary gland; long-standing deficiency of LH-RH may finally lead to a state of pituitary "functional" unresponsiveness to releasing hormones. In view of the excellent correlation between the base-line levels of LH and the absolute increment of LH following stimulation with LH-RH, this test only accentuates the existing pituitary secretory capacity, which can be roughly estimated from the circulating levels of LH and FSH. This test may be useful in distinguishing the milder cases of psychogenic amenorrhea from extreme gonadotrophic dysfunction in patients with anorexia nervosa.
SHORT-LOOP FEEDBACK MECHANISM OF LUTEINIZING HORMONE: LH STIMULATES HYPOTHALAMIC L-CYSTINE ARYLAMIDASE TO INACTIVATE LH-RH IN THE RAT HYPOTHALAMUS
Authors: Kuhl Herbert , Taubert Hans-Dieter 
Published: December 2008

ABSTRACT
The effect of the intravenous administration of several hormones on L-cystine arylamidase in the hypothalamus of the rat was examined. The injection of 10 μg LH into adult male and female rats was followed within 90 min by an increase of the enzyme activity by 50 %, while infantile animals were not affected. When prepuberal rats were pre-treated sc with testosterone and oestrogen respectively, the iv injection of LH brought about a rise in hypothalamic arylamidase activity. When ovariectomized rats were tested, no response was seen after LH injection unless the animals had been pre-treated with oestrogen and progesterone. The iv injection of 0.1 μg oestradiol-17β into female, and of 0.5 μg testosterone into male intact mature rats also resulted in an increase of hypothalamic enzyme activity. The maximal increase in enzyme activity was seen 16 h after steroid treatment. As it had previously been shown that L-cystine arylamidase inactivates LH-RH, it may be assumed that this enzyme is involved in the short-loop feedback of LH. This assumption is based on the observation that an elevation of plasma LH brings about an activation of the enzyme system, which subsequently leads to increased inactivation of LH-RH in the hypothalamus. This mechanism seems to depend on the presence of certain plasma levels of oestrogen in female, and of testosterone in male animals.
DIFFERENTIAL EFFECTS OF CASTRATION ON LH AND FSH SECRETION IN MALE AND FEMALE RATS
Authors: Zanisi M. , Martini L. 
Published: December 2008

ABSTRACT
Serum levels of LH and of FSH have been measured using specific radioimmunological procedures in normal controls and in male and female rats submitted to castration 1, 2, 7, 14, 21, 28 and 35 days before. Gonadectomy is followed by a rapid increase of serum levels of LH in males, and by a delayed response in females. The responses of serum FSH to castration are quantitatively and qualitatively similar in the two sexes. Both in males and in females an elevation of serum FSH levels is already present 1 day after the operation. Serum FSH continues to rise, between post-castration days 1 and 7 with a rather rapid slope, and at later intervals with a smoother progression.
THE INFLUENCE OF TIME, DOSE AND GONADAL STEROIDS ON LH-RH-INDUCED GONADOTROPHIN RELEASE IN RATS
Authors: Lotz Wolfgang 
Published: December 2008

ABSTRACT
Hypophyseal responses to LH-releasing hormone (LH-RH) were studied in ovariectomized rats, pre-treated once with 50 μg oestradiol-3-benzoate alone or in combination with 25 mg progesterone either 16, 24, 48 or 72 h before the administration of LH-RH. The highest serum gonadotrophin increase was detected in ovariectomized rats pre-treated with oestrogen 48 h before the LH-RH injection.
The serum LH concentration change in intact male rats was markedly lower in terms of order of magnitude than in ovariectomized, oestradiol-3-benzoate, progesterone-treated rats ("O. Oe. P."-rats). These latter test animals showed the maximal increase of serum LH concentration, depending on the dose of LH-RH, after 10 to 25 min and that of FSH after 40 min.
The dose-response curves for LH release in "O. Oe. P."-rats were linear for short (10 and 15 min) and sigmoid for longer time intervals (20, 30 and 40 min) between LH-RH injection and sacrifice.
The possible reasons for the difference in both magnitude and time-lapse for maximal increase of serum LH and FSH concentration, the influence of steroid pre-treatment and the variation of the time-course of serum LH concentration, depending on the dose of LH-RH, are discussed.
THE EFFECT OF ATROPINE ON INSULIN RELEASE CAUSED BY INTRAVENOUS GLUCOSE IN THE RHESUS MONKEY
Authors: Daniel P. M. , Henderson J. R. 
Published: December 2008

ABSTRACT
Glucose was given as a rapid intravenous injection to fasted anaesthetized rhesus monkeys, and the concentrations of blood glucose and plasma insulin were measured. Glucose caused a biphasic insulin response. The first phase (which was short) occurred 1 min after the injection; the second was longer, and occurred 17 to 30 min after the injection. Following the control glucose injection, each animal was given atropine, and the insulin response to an identical glucose stimulus was measured. This produced a mean reduction of 45 % in the area under the curve of insulin release. Both phases of insulin release were inhibited by atropine. When glucose was given alone, its mean half-time of disappearance from the circulation (t1/2) was 25.4 (± 1.9 sem) min. After atropine the mean t1/2 was 36.6 (± 3.1 sem) min, a significant difference. It is suggested that the delayed rate of disappearance of glucose from the circulation is the result of inhibition of insulin release by atropine.