bluuebunny/crossref_metadata_2025_split huggingface dataset:
16-DEHYDROGENASE IN HUMAN PLACENTA
Authors: Preumont P. , Smuk M. 
Published: December 2008

ABSTRACT
Human placental subfractions were incubated with radioactive oestriol and 16-oxo-oestradiol*. 16-oxo-oestradiol was identified from the oestriol incubation. Oestriol and 16-epi-oestriol were characterized from the incubation with 16-oxo-oestradiol. The 16α-dehydrogenase has been located in the soluble fraction (105 000 g supernatant) of the human placenta.
PRESENCE OF "RECEPTORS" FOR GROWTH HORMONE ON MEMBRANES OF RAT THYMOCYTES
Authors: Pandian M. R. , Gupta P. D. , Talwar G. P. , Avrameas S. 
Published: December 2008

ABSTRACT
Growth hormone conjugated to Sepharose-4 B was found to mimic the action of the free hormone in the stimulation of the uptake and incorporation of radioactive uridine into RNA in thymocytes in vitro. The integrity of the cellular structure was essential for the stimulating effect of the hormone. The binding of the immunologically reactive determinants of the hormone on membranes of thymocytes was demonstrated by electron micrographs of preparations incubated sequentially with rabbit antigrowth hormone globulins and monospecific sheep anti-rabbit globulins tagged with horse-radish peroxidase.
METABOLITES OF LYNESTRENOL ACETATE IN THE BILE OF RATS AFTER INTRAVENOUS ADMINISTRATION; A COMPARISON WITH LYNESTRENOL
Authors: Coert A. , Geelen J. , van der Vies J. 
Published: December 2008

ABSTRACT
Some aspects of the metabolism of lynestrenol acetate, an orally active contraceptive compound, were studied in female rats. Lynestrenol acetate is stable in gastric and intestinal juice in vitro. After intravenous administration of lynestrenol acetate and lynestrenol with a 14C label in the nucleus approximately 40 % of the administered radioactivity was excreted in the bile within 90 min. After administration of lynestrenol acetate labelled in the ester group, 6% of the radioactivity was found in the bile. This means that the greater part of the lynestrenol acetate had lost its acetate group during the process of metabolism.
There was an important difference between the autoradiograms of the thin layer patterns of post-hydrolysis extracts after administration of [4-14C]lynestrenol acetate and those after administration of [1′-14C]lynestrenol acetate and [4-14C]lynestrenol: the major metabolite of [4-14C]-lynestrenol acetate did not appear on the autoradiograms of [1′-14C]lynestrenol acetate and [4-14C] lynestrenol. This indicates that lynestrenol acetate was altered in the nucleus in the presence of the acetate group. The acetate group itself was removed, either when the alteration took place, or after it had been completed. The results of IR, NMR and mass spectrometry analysis indicate the introduction of a 15α hydroxyl group. Results of gas-liquid chromatography and thin layer chromatography indicate that a second important metabolite is 19-nor-17α-pregn-20-yne-3α, 17β-diol. The main conclusions are:
A part of the lynestrenol acetate is metabolized and excreted in the bile, the acetate group still being present. Lynestrenol acetate is to some extent metabolized via another pathway than lynestrenol. This indicates that esterification of a steroid can lead to deviation from the metabolic pathway of the free original steroid.
AGE DEPENDENT CHANGES IN IODINE METABOLISM AND THYROID FUNCTION
Authors: Hansen J. Mølholm , Skovsted Lis , Siersbæk-Nielsen K. 
Published: December 2008

ABSTRACT
Absolute iodine uptake (AIU), serum thyroxine (T4), free T4 index and serum triiodothyronine (T3) were studied in 48 women and 63 men aged 20 to 90 years. AIU decreased with age in both sexes to values in the oldest age groups of about 60 % of the values in the youngest age groups. AIU values for females were about 75 % of the values for males. Free T4 index was found to be unaltered with increasing age but serum T3 decreased with age. These findings and the previous demonstrated decrease in T4 degradation rate seem consistent with the assumption that T4 and T3 production decreases with advancing age.
GLUCOSE INHIBITION OF THE PERMEATION OF CHLOROMERCURIBENZENE-P-SULPHONIC ACID IN THE PLASMA MEMBRANE OF PANCREATIC β-CELLS
Authors: Söderberg Monica 
Published: December 2008

ABSTRACT
The transport of chloromercuribenzene-p-sulphonic acid (CMBS) was studied in microdissected pancreatic islets of ob/ob mice incubated in Krebs-Ringer bicarbonate medium. Glucose inhibited the islet uptake of CMBS. The initial binding of CMBS to superficial thiol groups was inhibited to a lesser extent than was its further permeation into the interior of the plasma membrane. The non-metabolized glucose analogue 3-0-methyl glucose had no effect on the permeation of CMBS. Whereas mannoheptulose, epinephrine and diazoxide lacked any effect in themselves, they tended to counteract the glucose inhibition of CMBS permeation. The ability of glucose to inhibit CMBS permeation is related to its insulin-releasing action rather than to its membrane transport or further metabolism.
A TRANSDUCER PROBE FOR THE DETECTION OF OESTROGEN EFFECTS ON VAGINAL BLOOD FLOW IN SHEEP
Authors: Benoit Henry J. , Borth Rudi , Woolever C. Allan 
Published: December 2008

ABSTRACT
A simple prototype vaginal probe was designed for the electronic detection of oestrogen-induced blood flow changes by measuring thermal conductivity, tissue temperature, and light reflectance. The probe was tested in six castrate ewes. Treatment with oestradiol-17β (1.0 mg, iv) produced marked changes in thermal conductivity and temperature, but had no detectable effect on reflectance. The study demonstrates the feasibility of multiple-sensor electronic probes for non-invasive monitoring of peripheral oestrogen effects in vivo.
RECEPTORS MEDIATING EPINEPHRINE EFFECT ON THYROID 131I UPTAKE AND THYROXINE SYNTHESIS IN THE RAT
Authors: Joasoo A. , Murray I. P. C. 
Published: December 2008

ABSTRACT
The adrenergic receptors mediating the inhibitory effect of epinephrine on the rat thyroid in vivo have been studied by the use of more specific alpha- and beta-adrenergic stimulators, and blocking agents. The effect of methoxamine was similar to that of epinephrine, while isoproterenol stimulated 131I uptake slightly, and did not alter the ratio of monoiodotyrosine (MIT) to diiodotyrosine (DIT). However, like methoxamine, isoproterenol resulted in a decrease in thyroxine (T4) formation. Phentolamine could partially prevent epinephrine-induced decrease in 131I uptake and T4 synthesis. The changes in the MIT/DIT ratio could be completely prevented by high doses of phentolamine. Propranolol enhanced the effects of epinephrine. It is concluded that the effect of epinephrine on the rat thyroid in vivo is predominantly alpha-adrenergic, but T4 synthesis may be decreased by stimulation of either receptor.
THE INFLUENCE OF SHORT TERM SUBMAXIMAL WORK ON THE PLASMA CONCENTRATIONS OF CATECHOLAMINES, PANCREATIC GLUCAGON AND GROWTH HORMONE IN MAN
Authors: Nilsson Karl Olof , Heding Lise G. , Hökfelt Bernt 
Published: December 2008

ABSTRACT
Studies were performed in 6 healthy, male volunteers to explore the effect of a work load on the blood concentrations of catecholamines in relation to pulse rate and blood pressure and the blood levels of pancreatic glucagon, insulin, growth hormone, glucose and glycerol. The work load consisted of 300 kpm/min for 5 min, followed by 600 kpm/min during the next 5 min and 900 kpm/min under a third 5 min period.
The work load resulted in a marked increase in noradrenaline and adrenaline at 10 and 15 min of exercise. The pulse rate, the systolic pressure and the mean blood pressure were correlated to the blood levels of both adrenaline and noradrenaline.
In spite of the rather marked activation of the sympathetic nervous system no increase occurred in glucagon as measured under exercise and up to 60 min after its completion. In 4 of the subjects the work load was followed by a prompt growth hormone response. The same 4 subjects also showed a marked increase in catecholamines. The 2 remaining subjects presented no change in growth hormone and their increase in catecholamines was relatively minor.
Glycerol increased significantly during work and there was a positive correlation between the values recorded for glycerol and adrenaline.
No significant changes occurred in blood sugar or insulin during work.
COMBINATION CONTRACEPTIVE EFFECTS ON MONTHLY CYCLE OF PLASMA ALDOSTERONE, RENIN ACTIVITY AND RENIN SUBSTRATE
Authors: Katz Fred H. , Romfh Peggy , Smith Judith A. , Roper Ellen F. , Barnes John S. 
Published: December 2008

ABSTRACT
A post-ovulatory peak of fasting supine plasma aldosterone (PA) preceded or accompanied by an increase in plasma renin activity (PRA) was previously reported. These studies have now been extended in 4 additional normal menstruating women and 4 women taking oestrogen-progestogen oral contraceptive pills (OCP), all studied daily for an entire cycle. Distinct luteal phase increases in PRA were seen in the 4 normals, with 2 also demonstrating a rise in PA. Plasma renin substrate (PRS) was usually unvarying throughout the control cycles. The women taking OCP, on the other hand, all had PA and PRA peaks that were apparent by the fourth or fifth day of taking "the pill". All 4 of the treated women had elevated PRS levels but only one woman showed an increase which preceded the elevation of PRA and PA. Plasma cortisol levels were usually above the normal range in the women taking OCP. This study thus indicates that factors other than oestrogen-induced increased substrate production may be responsible for the PRA and PA rise during OCP treatment Such factors might be the natri-uretic effects of oestrogens and progestogens or a direct effect on renin secretion by one of these steroids.
THE ONTOGENY AND REGULATION OF CORTICOSTEROID SECRETION BY THE OVINE FOETAL ADRENAL
Authors: Wintour E. Marelyn , Brown Elizabeth H. , Denton D. A. , Hardy K. J. , McDougall J. G. , Oddie Catherine J. , Whipp G. T. 
Published: December 2008

ABSTRACT
Adrenal glands of foetal sheep of 40 days gestation to term were incubated with and without ACTH or an increased [K+]. With ACTH, the 40 day foetal adrenal was capable of producing more cortisol and aldosterone per g body weight than was the term adrenal. ACTH was a potent stimulus to aldosterone and cortisol production in foetuses aged 60–90 days, and this effect declined significantly in the 91–120 day period. An increased [K+] was stimulatory to aldosterone production only after 120 days gestation. Peripheral blood levels of aldosterone, corticosterone, cortisol, 11-deoxycortisol and 11-deoxycorticosterone were measured in foetuses 60 days to term and the levels of aldosterone and cortisol were significantly lower in 90–120 day foetuses than in the younger or older ones. Direct adrenal vein cannulation proved all five steroids to be secretory products of the foetal adrenal.
EFFECT OF POST-OVULATORY ADMINISTERED OESTROGENS ON CORPUS LUTEUM FUNCTION
Authors: Lehmann F. , Just-Nastansky I. , Behrendt B. , Czygan P.-J. , Bettendorf G. 
Published: December 2008

ABSTRACT
The effect of orally given diethylstilboestroldiphosphate (DES) and 17α-ethinyl-oestradiol-3-methylether (EEM) on plasma progesterone levels was studied. Both compounds were administered for 5 days to 5 women in daily doses of 60 mg (DES) and 30 mg (EEM). The fully informed volunteers were found to have a normal menstrual cycle before the study. The mean corpus luteum phase (corpus luteum phase = days between LH surge and onset of menstruation) of all control cycles lasted 12.8 days. Daily plasma samples were collected for radioimmunoassay (RIA) of progesterone, immunoreactive oestrogens and LH. After a control cycle the first treatment was carried out with DES. The third and the fifth cycle were control cycles again. The EEM-treatment was done in the fourth cycle. Although the effect of the two compounds was different, a dependence of the age of the corpus luteum (CL) could be demonstrated for both. DES-treatment lowered plasma progesterone levels during administration. This effect was only demonstrable if the treatment was begun on the day of the LH-peak. The length of the CL-phase remained unaltered. EEM-treatment if started on the day of the LH surge, suppressed corpus luteum function in the late luteal phase. If the treatment was started later, the effect was less pronounced. The administration of both compounds did not shorten the time between ovulation and the next bleeding. After DES-treatment this interval was not altered. After EEM-treatment the subsequent bleeding was even delayed depending on slowly decreasing levels of plasma oestrogens.
PLASMA DIHYDROTESTOSTERONE IN NORMAL ADULT MALES AND ITS RELATION TO TESTOSTERONE
Authors: Pirke Karl M. , Doerr Peter 
Published: December 2008

ABSTRACT
A radioimmunoassay for dihydrotestosterone (DHT) in plasma was developed using an antiserum raised against testosterone-3-oxime-bovine-serum-albumin. After extraction of 1 ml male plasma with diethylether, DHT was separated from testosterone (T) by thin-layer chromatography. A dextran-charcoal-suspension was used for the separation of bound and free ligand. The inter-assay variability was 10.4 % (C. V.) and the detection limit 1.77 ng/100 ml. The accuracy of the method as determined by mass recoveries and the specificity were shown to be satisfactory.
Normal values were obtained in 45 young to middle-aged (22–61 years) and 37 old (68–93 years) men. The median and the 95 percentiles were 20.5–51.9–76.3 (ng/100 ml) and 19.5–50.9–101.5 (ng/100 ml) respectively. While DHT did not change in old age T fell by 20.6%. DHT and T showed a significant correlation: rS = 0.426, P < 0.01 (young men), rS = 0.752, P < 0.001 (old men).
After 3 daily im injections of 5000 IU human chorionic gonadotrophin (HCG), DHT increased 1.50 times (range: 1.15–2.09, n = 12), T 1.86 times (range: 1.20–2.91, n = 12). After 4 daily administrations of 40 mg fluoxymesterone DHT fell to 29.6% of the control level (range: 16.0–48.2%, n = 12).
Blood samples were obtained from a 24 year old man every 15 min for 24 h. A close parallelism was observed between the concentrations of DHT and T in the plasma.
PLASMA ANDROGEN LEVELS IN MEN AFTER ORAL ADMINISTRATION OF TESTOSTERONE OR TESTOSTERONE UNDECANOATE
Authors: Nieschlag E. , Mauss J. , Coert A. , Kićović P. 
Published: December 2008

ABSTRACT
Plasma testosterone and androstenedione levels in men were measured after oral administration of free testosterone and testosterone undecanoate. Both androgens were determined by simultaneous, specific radioimmunoassays after separation and isolation by thin layer chromatography.
While free unesterified testosterone had no effect on plasma androgen levels, a striking increase of both testosterone and androstenedione levels was noted after administration of testosterone undecanoate, which is otherwise only achieved by parenteral testosterone application. This effect of testosterone undecanoate is probably due to absorption via the lymph rather than via the portal vessels so that peripheral circulation is reached before metabolism in the liver. Testosterone undecanoate promises to be an effective medication for oral androgen replacement.
EFFECT OF TRANSPLANTATION OF THE FOETAL TESTIS TO NEONATAL FEMALE RATS ON DIFFERENTIATION OF THE POSTPUBERTAL SECRETORY PATTERN OF GONADOTROPHIN
Authors: Arai Y. , Serisawa K. , Kigawa A. 
Published: December 2008

ABSTRACT
Rat foetal testes (day 19 or 20 pregnancy) were transplanted into the neck of 3-day-old female rats. When testicular grafts were left in the recipients until autopsy (at 90 days of age), anovulatory persistent oestrous syndrome developed in most of the recipient females. These changes were not influenced by the removal at 45 days of age of the testicular grafts. However, the incidence of anovulatory sterility was significantly reduced when the foetal testicular grafts had been removed 5 days after transplantation. Treatment of these recipient females with 40 IU HCG from the day of the transplantation to the day before the removal of the transplants markedly increased the incidence of anovulatory sterility in the recipient females. In histological examinations of the testicular grafts upon their removal, a significant stimulation of Leydig cell elements was noted in the groups of rats treated with HCG. It is highly probable that if sufficient levels of gonadotrophin (GTH) are present in the recipient females, testicular tissues from day 18–20 foetuses can secrete sufficient amounts of androgen for masculinizing GTH regulation.
CORRELATION OF DIAMETERS OF SECRETORY GRANULES IN CLINICALLY NON-FUNCTIONING CHROMOPHOBE ADENOMAS OF THE PITUITARY WITH THOSE OF NORMAL THYROTROPHS
Authors: Gray A. B. , Doniach I. , Leigh P. N. 
Published: December 2008

ABSTRACT
Diameters of secretory granules in thyrotrophs and in gonadotrophs were measured in electron micrographs of operation specimens of 4 pituitary glands and of the secretory granules in operation specimens of 10 clinically non-functioning chromophobe adenomas. The mean diameter of the thyrotroph granules was 137 ± 26 nm, of the gonadotrophs 204 ± 38 nm, of 9 of the adenomas 141 ± 20 nm and of the remaining adenoma 248 ± 67 nm. The significance of the close correlation in granule size in most of the adenomas with that of thyrotrophin granules is discussed briefly.
POTENTIATION OF INSULIN RELEASE BY GLUCOSE IN MAN
Authors: Cerasi Erol 
Published: December 2008

ABSTRACT
The effect of repeating a 60 min glucose infusion at a 40 to 70 min interval was investigated after an overnight fast in 14 healthy, non-obese subjects with normal glucose tolerance and normal insulin response to glucose administration. When a hyperglycaemic plateau of around 300 mg/100 ml was induced by the first glucose infusion, the insulin response to a second challenge was enhanced over the range of stimulations used. Both the early and late phase insulin responses were amplified, the enhancement being more marked with higher stimulatory levels of glucose. The blood glucose-insulin dose-response curve became steeper after pretreatment with glucose, the stimulatory threshold level not being altered. These findings suggest that the synergism between the glucose pretreatment, and the insulin releasing effect of glucose, is of multiplicative type, resulting in increase of the maximum effect of the glucose.
The dose-dependency of this potentiation was investigated by keeping the second glucose challenge at a constant level and altering the dose of the first infusion. It was necessary to reach hyperglycaemias around and above 300 mg/100 ml during the first infusion in order to obtain enhancement of the insulin response to the second stimulus. The dose-response curve of the potentiating effect of glucose is thus displayed towards the right when compared with that describing the insulin releasing effect of glucose, which has its threshold around 100 mg/100 ml.
It is suggested that glucose exerts a dual effect on the pancreatic islets: an immediate one which initiates the release of insulin, and a time-bound one which modulates the first action.
POTENTIATION OF INSULIN RELEASE BY GLUCOSE IN MAN
Authors: Cerasi Erol 
Published: December 2008

ABSTRACT
If two consecutive glucose infusions are administered with 40 min of rest between, the insulin response to the second challenge is markedly potentiated. When the insulin response to the first glucose infusion was suppressed by 65 % with the aid of adrenaline, potentiation of the insulin response to the second infusion was not modified. This suggests that the generation of a state of enhancement in the islet does not necessitate that glucose exerts its insulin releasing action. It is postulated that islet glucose metabolism may be involved in producing the potentiation.
Pretreatment of the subjects with a glucose infusion enhanced also the insulin responses to glucagon and to tolbutamide, given intravenously 50 min later. Thus, the potentiation generated by glucose is not restricted to the insulinogenic signal induced by glucose. The eventual role that the beta-cell adenylate cyclase may play in this respect is discussed.
THE EXCRETION OF INDIVIDUAL ADRENOCORTICAL STEROIDS DURING NORMAL CHILDHOOD AND ADOLESCENCE
Authors: Savage D. C. L. , Forsyth Constance C. , McCafferty Eileen , Cameron Jenny 
Published: December 2008

ABSTRACT
The excretion of 7 individual 17-oxosteroids and 7 individual corticosteroids in 24 h urine samples from 62 normal infants, children and adolescents, based on an accurate and specific paper chromatographic method for their separation and quantitation, is reported. The excretion of the 11-deoxy-17-oxosteroids gradually increases from 7 years of age and the increase becomes more rapid 2 or 3 years before the clinical signs of puberty appear. The rise continues throughout puberty and beyond it until the adult level is reached. The increase far exceeds that which would be accounted for by the growth of the individual. The increase in the excretion of the 11-oxy-17-oxosteroids with age is much more gradual. Androgens favour the formation of 5α metabolites and the 5α:5β ratio of the total 5α 17-oxosteroids and the total 5β 17-oxosteroids shows a statistically significant increase with age. In addition, a relatively high 5α:5β ratio is noted in male infants, which is likely to be related to their relatively high plasma testosterone levels. The excretion of the 17-hydroxycorticosteroids and the α-ketolic metabolites of cortisol gradually rises with age and correlates with body weight. The α-ketolic metabolites of corticosterone are relatively high in infancy, but after the age of 4 years their excretion also correlates with body weight. An increase in the 5α:5β ratio of allo-THF to THF is noted at puberty similar to that found with the 5α:5β ratios of the 17-oxosteroids.
THE LH-hCG RECEPTOR OF HUMAN OVARY AT VARIOUS STAGES OF THE MENSTRUAL CYCLE
Authors: Wardlaw S. , Lauersen N. H. , Saxena B. B. 
Published: December 2008

ABSTRACT
Receptors specific for hCG were found in human corpora lutea and follicles. hCG and LH were found to bind at a similar receptor site. The dissociation constant for hCG ranged from 10−10 to 10−11 mol/l in human corpora lutea. The number of binding sites for 125I-hCG ranged from 10−14 to 10−15 moles/mg protein in human corpora lutea. The binding of 125I-hCG to ovary was found to vary at different stages of the menstrual cycle. The binding of 125I-hCG to human ovaries increased on days 13–15 of the cycle, then declined slightly, and increased again on days 22–23. Following day 23, there was a slow decline until day 27 when binding activity could no longer be measured. No binding could be measured by the corpus luteum after the onset of menstruation or in corpora albicans.
IMPLANTATION AND MAINTENANCE OF PREGNANCY IN MATED RHESUS MONKEYS FOLLOWING BILATERAL OOPHORECTOMY OR LUTEECTOMY WITH AND WITHOUT PROGESTERONE REPLACEMENT
Authors: Bosu William T. K. , Johansson Elof D. B. 
Published: December 2008

ABSTRACT
Six mated rhesus monkeys were bilaterally oophorectomised between the fourth and sixth day after ovulation, and received silastic implants containing crystalline progesterone subcutaneously. Five mated monkeys were subjected to luteectomy 5 or 6 days after ovulation. Three of these received progesterone implants subcutaneously. Pregnancy occurred in one oophorectomised monkey and in all three luteectomised monkeys treated with progesterone. It was evident from the steroid patterns observed in the pregnant monkeys that the ovarian tissue other than the corpus luteum contributes to part of the oestrogen seen around the time of implantation. The corpus luteum appears to be the main source of progesterone in the peripheral plasma during this period. Placental progesterone production in early pregnant rhesus monkeys starts at three weeks after ovulation and the placental production of progesterone precedes that of oestrogen.