bluuebunny/crossref_metadata_2025_split huggingface dataset:
THYROID FUNCTION IN PROTEIN-DEPLETED RATS
Authors: FLORSHEIM W. H. , SUHR BIRUTA Z. , MIRISE R. T. , WILLIAMS A. D. 
Published: December 2008

SUMMARY
Renal iodide clearance in rats was reduced rapidly when the animals were fed a protein-depletion diet. If the iodine content of the protein-depletion diet is high, this results in an increase in the serum iodide levels to concentrations in excess of 150 μg./100 ml. Protein-bound iodine was elevated due to the accumulation of iodinated serum albumin. Thyroid hormonal iodoamino acid content was transiently depressed, presumably by the mechanism described by Wolff & Chaikoff (1948). Thyroxine metabolism was not affected except for a change in the partition of thyroxine between liver and serum. There was no evidence for pituitary involvement in the effects of protein depletion on thyroid function.
URINARY EXCRETION OF LUTEINIZING HORMONE IN BOYS AND ADULT MEN
Authors: SCIARRA N. , LEONE U. 
Published: December 2008

SUMMARY
The daily urinary excretion of luteinizing hormone (LH) was determined in 15 boys, aged 5–11 yr., and in 15 adult men, aged 18–65 yr., by an immunological method using the haemagglutination inhibition system.
The hormone was detected in every subject investigated. The mean value for urinary LH excretion in boys was equivalent to 3·4 i.u./24 hr. (range 1·3–6·5) and was 29·3 i.u./24 hr. in adults (range 15·4–44·6). The mean adult: child ratio was 8·6.
There was a significant increase in LH output with age in both the boys and the men; the rate of this increase was the same in both groups. However, there was a sharp rise in hormone output at about the onset of puberty.
THE RESPONSE OF PLASMA INSULIN, GLUCOSE AND NON-ESTERIFIED FATTY ACIDS TO VARIOUS HORMONES, NUTRIENTS AND DRUGS IN THE DOMESTIC FOWL
Authors: LANGSLOW D. R. , BUTLER E. J. , HALES C. N. , PEARSON A. W. 
Published: December 2008

SUMMARY
The relationships between plasma insulin, glucose, non-esterified fatty acid (NEFA) and α-amino nitrogen concentrations in the domestic fowl have been studied. During a 72-hr. fast the plasma glucose concentration fell while the NEFA concentration rose but there was no change in plasma insulin concentration. Both oral and intracardiac glucose increased the plasma insulin concentration and lowered the plasma NEFA and α-amino nitrogen concentrations. Oral amino acids increased plasma insulin and glucose concentrations but had no effect on plasma NEFA. Intracardiac ox insulin depressed plasma glucose and α-amino nitrogen and increased the plasma NEFA concentration. Intracardiac glucagon increased both plasma glucose and NEFA and depressed the plasma α-amino nitrogen concentrations but had no significant effect on plasma insulin. Intracardiac adrenaline had no effect on plasma NEFA but increased plasma glucose concentration and caused a small depression in plasma insulin concentration.
THE BLOOD LEVELS OF OXYTOCIN DURING MACHINE MILKING IN COWS WITH SOME OBSERVATIONS ON ITS HALF-LIFE IN THE CIRCULATION
Authors: CLEVERLEY JACQUELINE D. , FOLLEY S. J. 
Published: December 2008

SUMMARY
Blood oxytocin was assayed on the lactating guinea-pig mammary gland.
Transient release of oxytocin was detected in the range of 9–889 μu./ml. plasma in the external jugular vein blood of cows during machine milking. In 24 experiments oxytocin was detected in 17; in nine of these, hormone release by conditional reflex was obtained in response to auditory or visual stimuli associated with the milking routine. All stimuli associated with the milking routine caused oxytocin release. There was no difference in the plasma concentrations detected in response to conditional and nonconditional stimuli. In this and previous work no release of oxytocin was detected in 32% of experimental machine milkings although in most cases milk yields were normal.
Milk ejection was accompanied by increases in intramammary pressure from 12·5–24 mm. to 23–44 mm. Hg; the pressure after ejection was maintained virtually constant for over 1 hr. There was no initial drop in pressure, associated with a neural segmental reflex. Rise in intramammary pressure accompanied the detection of oxytocin in jugular blood in four out of seven experiments. The pressure changes and latency could be simulated by rapid intravenous injection of 100 m-u. synthetic oxytocin. The half-life of synthetic oxytocin in the circulation was 127 ± 9·3 sec. (range 85–164 sec.).
STUDIES ON THE BIOSYNTHESIS OF ALDOSTERONE USING THE SHEEP ADRENAL TRANSPLANT: EFFECT OF SODIUM DEPLETION ON THE CONVERSION OF CORTICOSTERONE TO ALDOSTERONE
Authors: BLAIR-WEST J. R. , BRODIE A. , COGHLAN J. P. , DENTON D. A. , FLOOD C. , GODING J. R. , SCOGGINS B. A. , TAIT J. F. , TAIT S. A. S. , WINTOUR E M. , WRIGHT R. D. 
Published: December 2008

SUMMARY
The effect of sodium depletion on the conversion of corticosterone to aldosterone has been examined in vivo using the adrenal transplants of two sheep. [3H]Corticosterone was infused continuously directly into the adrenal gland via the carotid artery over a period of 30 min. and the total adrenal effluent was collected via the jugular vein in six consecutive 5-min. samples. The conversion of [3H]corticosterone to [3H]aldosterone and the endogenous output of aldosterone was measured in each sample using a double isotope derivative method and the specific activity of the aldosterone calculated. Radioactive conversion of B → aldosterone reached equilibrium within 10 min. of the start of infusion and remained constant over a period of 10–25 min. Aldosterone secretion was also constant during the first 25 min. of infusion.
In the same sheep the mean percentage conversion increased as aldosterone secretion rose over a range of 2–12 μg./hr. With more severe sodium depletion, i.e. with aldosterone secretion rates of 12–16 μg./hr., conversion decreased to that found in the sodium replete state. The specific activity of the aldosterone was constant throughout the mildly deplete range (2–12 μg./hr.) but fell with severe sodium depletion. In the sodium replete range (0–2 μg./hr.) before the introduction of a parotid fistula, the specific activity was the same as in the mildly deplete state. After the introduction of a parotid fistula the specific activity increased as the secretion decreased from 2 to 0 μg.
The validity of the approach and interpretation of the results in terms of the biosynthetic pathways involved are discussed.
OOCYTE SURVIVAL IN THE MOUSE OVARY AFTER TREATMENT WITH 9,10-DIMETHYL-1,2-BENZANTHRACENE
Authors: KRARUP T. 
Published: December 2008

SUMMARY
The induction of ovarian tumours in mice by 9,10-dimethyl-1,2-benzanthracene (DMBA) is preceded by the disappearance of oocytes and follicles.
The effect of DMBA on the oocyte population was determined in immature and in mature mice by performing total and differential oocyte counts at different intervals after oral and intraperitoneal administrations of the carcinogen.
In orally treated animals the number of small oocytes was quickly reduced followed by a decrease in the number of growing and large oocytes; in addition, in intraperitoneally treated animals, some growing and large oocytes were directly destroyed.
The sensitivity of the germ cells to DMBA was independent of the age of the animals.
In normal mice, as well as in immature mice treated with DMBA, the number of small oocytes determined the proportion which was stimulated to develop into growing and large oocytes.
THE DEVELOPMENT OF A RADIOIMMUNOASSAY FOR OXYTOCIN: SENSITIVITY OF THE ASSAY IN AQUEOUS BUFFER SOLUTION, SPECIFICITY AND THE DISSOCIATION OF IMMUNOLOGICAL AND BIOLOGICAL ACTIVITY
Authors: CHARD T. , FORSLING M. L. , JAMES M. A. R. , KITAU M. J. , LANDON J. 
Published: December 2008

SUMMARY
A radioimmunoassay for oxytocin in aqueous solution is described, with a sensitivity comparable with the best current bioassays. It is highly specific; arginine-vasopressin and lysine-vasopressin interfere only at 1000-fold greater concentration, while bradykinin, histamine, acetycholine and many other substances, which interfere with some bioassays, have no effect. In certain circumstances, there is a dissociation between loss of biological and immunological activity. Thus reducing agents had no effect on immunological activity, in contrast to their effect on biological activity. In late pregnancy plasma, the biological activity of oxytocin is destroyed more rapidly than the immunological activity. Radioimmunoassays have considerable advantages over bioassays both in convenience and specificity. However, bioassays should be employed for reference purposes because of the dissociation between biological and immunological activity that may occur.
THE ROLE OF THE DORSAL TRACTS OF THE SPINAL CORD AND OF THE MESENCEPHALIC AND THALAMIC LEMNISCAL SYSTEM IN THE MILK-EJECTION REFLEX DURING MILKING IN THE EWE
Authors: RICHARD PH. , URBAN I. , DENAMUR R. 
Published: December 2008

SUMMARY
The milk-ejection reflex after different lesions of the sensory system was studied by mechanical milking of the ewe. Only animals with lesions which did not produce locomotor ataxia were investigated. Section of the dorsal tract of the spinal cord at different thoracic levels blocked the milk-ejection reflex. This was not due to postoperative shock, because the same type of lesion made at the sacral level was without effect. Moreover, unilateral section of this tract blocked the reflex when milking was limited to the ipsilateral mammary gland. At the cervical level, the interruption of the dorsal tract was ineffective, which can probably be explained by the existence, in sheep, of the spino-cervico-thalamic tract. The latter becomes ventral at the cervical level. Lesions of the lemniscal system in the mesencephalon (bilateral coagulation of the medial lemniscus) and in the thalamus (bilateral destruction of the ventral posterolateral nucleus) do not inhibit the milk-ejection reflex.
The role of the spinal lemniscal system is discussed in relation to the work of others and to the electrophysiological results obtained by one of us. It is suggested that two sensory systems (lemniscal and extralemniscal) have to interact to induce the release of oxytocin evoked by the stimuli of mammary origin during milking.
INCREASE IN PLASMA GROWTH HORMONE CONCENTRATION IN MAN AFTER INFUSION OF ADRENALINE-PROPRANOLOL
Authors: MASSARA F. , STRUMIA E. 
Published: December 2008

SUMMARY
Plasma human growth hormone (HGH) concentrations were compared during four tests in which 0·9% NaCl solution only, propranolol, adrenaline or propranolol plus adrenaline were infused into six healthy volunteers. In five subjects, HGH levels during the infusion of saline, propranolol or adrenaline showed no significant increase and were virtually identical. During the test with propranolol plus adrenaline, however, there was an increase after adrenaline in spite of concomitant hyperglycaemia. The sixth volunteer showed a wide range of apparently spontaneous and irregular variations in HGH values throughout each of the four tests.
These findings support the view that α-receptors stimulate and β-receptors depress HGH secretion, and show that adrenergically stimulated HGH secretion in man is not inhibited by hyperglycaemia.
THE ADENOHYPOPHYSIS OF FEMALE RATS AFTER HYPOTHALAMIC OESTRADIOL IMPLANTS: AN ELECTRON MICROSCOPIC STUDY
Authors: ZAMBRANO D. , DEIS R. P. 
Published: December 2008

SUMMARY
The ultrastructural effect of oestradiol implants into the hypothalamus on the adenohypophysis of adult female rats was studied. The main results are the demonstration that mammotrophs or prolactin cells, and to a lesser extent somatotrophs, increased their secretory activity after bilateral implants into the median eminence and arcuate nuclei; in the periventricular area the reaction was weaker and in the anterior hypothalamus the response was negative. In animals with implants in the basal tuberal region, mammotrophs showed an asynchronous secretory activity. Mitosis has been found to occur in fully differentiated mammotrophs, a finding which can be correlated with the increased number of such cells after basal tuberal implants. The gonadotrophs appeared to be atrophied.
EFFECT OF CORTICOTROPHIN AND CORTICOSTEROIDS ON OESTRUS, OVULATION AND OESTROGEN EXCRETION IN THE SOW
Authors: LIPTRAP R. M. 
Published: December 2008

SUMMARY
Corticotrophin (ACTH), hydrocortisone or prednisolone trimethylacetate were administered daily to sows from 24 hr. before oestrus or from day 14 of the cycle until the end of oestrus. Treatment beginning on day 14 delayed the peak in urinary oestrogen excretion normally seen, postponed the onset of oestrus by 1–3 days and shortened the duration of oestrus. Treatment begun before oestrus did not appear to alter the pattern of oestrogen excretion but shortened the duration of oestrus. Administration of ACTH, but not that of corticosteroids, also interfered with ovulation.
THE RATES OF PLASMA CORTISOL ENTRY AND CLEARANCE IN SHEEP BEFORE AND DURING THEIR EXPOSURE TO A COLD, WET ENVIRONMENT
Authors: PANARETTO B. A. , VICKERY MARION R. 
Published: December 2008

SUMMARY
Plasma cortisol concentrations and entry rates increased greatly when nine shorn sheep were exposed to cold, wet conditions for periods up to 70 hr. The average entry rate in four of the cold-stressed animals before their rectal temperatures began to fall was 25 μg./min., approximately three to four times greater than in the same sheep before exposure (7·7 μg./min.). The metabolic clearance rates at this time remained unchanged. Plasma cortisol concentration began to increase about 2–3 hr. before the sheeps' rectal temperatures began to fall. The increase continued until concentrations of 100–200 μg./1. were reached after the sheeps' rectal temperature had fallen. Cortisol entry increased at this time to what may probably be maximal or near maximal rates in the sheep (about 150–200 μg./min.). Lowered clearance did not appear to contribute substantially to increased plasma cortisol concentrations at rectal temperatures above 34°. Since clearance rates did not begin to fall rapidly until rectal temperature fell below about 34°, cortisol entry during the terminal phase of hypothermia, approximately 76 μg./min., was very much less than the observed maximum and the high plasma cortisol concentrations measured during this period were residual and sustained by lowered clearance rates.
The adrenal cortices and livers of the sheep after severe hypothermia were heavily infiltrated with fat.
The effects of shearing alone, studied in a separate experiment, had a transitory effect since plasma cortisol concentrations and entry rates had returned to near their pre-shearing levels by about 27 hr.
CARBON DIOXIDE PRODUCTION BY MOUSE BLASTOCYSTS DURING LACTATIONAL DELAY OF IMPLANTATION OR AFTER OVARIECTOMY
Authors: MENKE TERESA M. , McLAREN ANNE 
Published: December 2008

SUMMARY
The rate of CO2 production by 8-cell embryos (2½ days post coitum) and blastocysts (3½ days post coitum) was measured in mice of the Q strain. The values for blastocysts resembled those obtained by Brinster (1967) in the Swiss strain, both in mean and variance; the values for 8-cell eggs differed in both respects from those obtained by Brinster.
Blastocysts in delay of implantation during lactation or after ovariectomy gave off less CO2 per hr. than either 3½-day blastocysts from normal pregnancies or blastocysts from post-partum matings when the litters were removed at birth. This indicates that blastocysts enter a state of metabolic dormancy during delay of implantation.
When ovariectomized pregnant mice were maintained on 0·5 mg. progesterone per day, their blastocysts produced even less CO2/hr. than those from ovariectomized animals not given exogenous hormone. The implications of this finding are considered with respect to the role of progesterone in delay of implantation.
THE EFFECTS OF OESTROGEN AND PROGESTERONE ON THE SODIUM AND POTASSIUM CONCENTRATIONS OF RAT UTERINE FLUID
Authors: CLEMETSON C. A. B. , MALLIKARJUNESWARA V. R. , MOSHFEGHI M. M. , CARR J. J. , WILDS J. H. 
Published: December 2008

SUMMARY
Studies of the electrolyte concentrations of uterine fluid samples from spayed rats, after injection of ovarian hormones, showed a much higher potassium concentration after treatment with oestrogen (42·3 m-equiv./1.) than with progesterone (20·8 m-equiv./1.). There was an even more pronounced change in the sodium: potassium ratio, which fell from 7·3 to 1 with progesterone to 2·5 to 1 with oestrogen. These findings are supported by recalculation of the results of Heap & Lamming (1962).
It is suggested that these changes in the Na+ and K+ concentrations of uterine fluid produce changes in the membrane potential of the endometrium which could account for delayed implantation of the negatively charged blastocyst under progesterone dominance and implantation under oestrogen dominance.
PATTERNS OF STEROID BIOSYNTHESIS BY HUMAN ADRENALS INCUBATED IN VITRO WITH [7α-3H]PREGNENOLONE: CHANGES WITH (a) GESTATIONAL AGE, (b) INCUBATION PERIOD AND (c) WEIGHT OF INCUBATED TISSUE
Authors: MILNER A. JOSEPHINE , MILLS I. H. 
Published: December 2008

SUMMARY
Human adrenal tissue was sliced and incubated with 25 μc [7α-3H]-pregnenolone. The percentage conversion of radioactive precursor to dehydroepiandrosterone (DHA), DHA sulphate, androstenedione, 11β-hydroxyandrostenedione, cortisol and 11-deoxycortisol was estimated by the reverse isotope dilution technique. Incubations of both adult and foetal adrenal slices gave reproducible results. The duration of the incubation period was an important factor affecting the pattern of radioactive steroids synthesized, the adult adrenal pattern being dissimilar to that of the foetal adrenal. A direct proportional relationship between the weight of the incubated tissue and the biosynthesis of cortisol from exogenous [7α-3H]-pregnenolone was not established.
The production of DHA sulphate relative to free DHA increased markedly from 12 to 27 weeks gestation. When incubated for 2 hr. the combined production of DHA and DHA sulphate relative to cortisol and androstenedione decreased with gestational age. There was evidence for considerable 3β-hydroxysteroid dehydrogenase activity in foetal adrenals at 12 to 27 weeks gestation.
THE EFFECT OF NEUROHYPOPHYSIAL HORMONES ON THE AMPHIBIAN OVIDUCT IN VITRO, WITH SOME REMARKS ON THE HISTOLOGY OF THIS ORGAN
Authors: HELLER H. , FERRERI ELENA , LEATHERS D. H. G. 
Published: December 2008

SUMMARY
The effect of neurohypophysial hormones has been tested in vitro on oviducts of four species of urodele and three species of anuran Amphibia. Contractile responses were obtained with all the hormones used but 8-arginine oxytocin (vasotocin) was usually most potent. The sensitivity of the oviducts varied widely from species to species; there were also pronounced seasonal differences within a species. Histological investigations yielded some information on the abundance and arrangement of muscle fibres in amphibian oviducts. A simple and sensitive (magnification up to × 1000) recording system for isotonic contractions is described.
THYROID FUNCTION AND STEROID HORMONE EXCRETION
Authors: MILLER H. , DURANT J. A. , COWAN JOYCE M. , KNOTT J. M. S. , GARNETT E. S. 
Published: December 2008

SUMMARY
The excretion of steroid hormone metabolites was studied in normal, thyrotoxic and myxoedematous subjects. Corticosteroid excretion was increased in thyrotoxicosis and reduced in myxoedema.
In myxoedema there was also a fall of total androgen excretion due principally to a reduction of the androsterone component.
There was no change in total androgen excretion in thyrotoxic subjects, but there was a fall of aetiocholanolone excretion.
THE RESPONSE OF THE SEBACEOUS GLANDS OF HYPOPHYSECTOMIZED—CASTRATED MALE RATS TO ADRENOCORTICOTROPHIC HORMONE AND TO TESTOSTERONE
Authors: EBLING F. J. , EBLING ERIKA , SKINNER J. , WHITE AUDREY 
Published: December 2008

SUMMARY
Administration of 1 i.u./24h of adrenocorticotrophic hormone (Cortrophin ZN, ACTH) to hypophysectomized—castrated rats significantly increased sebum production to the level of that in castrated rats with intact pituitaries. The incidence of mitoses in the sebaceous glands was also significantly increased. Neither the preputial glands nor the seminal vesicles showed any response.
No significant increase in sebum production in hypophysectomized—castrated rats could be detected 24 days after giving implants releasing 0·2 or 0·6 mg testosterone/24 h, although sebaceous mitoses were significantly increased in both instances. Concomitant administration of both ACTH and testosterone raised sebum production to the same extent as ACTH alone, and raised the incidence of sebaceous mitoses to a level equal to that produced by ACTH plus testosterone.
It is concluded that the sebaceous glands respond—either directly or indirectly as the result of stimulation of the adrenal cortex—to ACTH and that this response is less dependent on the presence of the pituitary than is the action of testosterone. ACTH does not itself facilitate the response of the sebaceous glands to testosterone.
RNA SYNTHESIS IN THE RAT ANTERIOR HYPOTHALAMUS AND PITUITARY: RELATION TO NEONATAL ANDROGEN AND THE OESTROUS CYCLE
Authors: SALAMAN D. F. 
Published: December 2008

SUMMARY
RNA from the anterior hypothalamus and anterior pituitary of rats has been labelled by incubation in vitro with [3H]uridine and characterized by density gradient centrifugation. A study of normal females during the oestrous cycle showed cyclic changes in [3H]uridine incorporation into rapidly labelled RNA (rl-RNA) both in the anterior pituitary and hypothalamus. In both tissues the specific activity of RNA was low at dioestrus and high at oestrus and metoestrus. In androgenized females, incorporation into hypothalamic rl-RNA was less than the oestrus—metoestrus level and similar to that at dioestrus, while incorporation into anterior pituitary rl-RNA was similar to the oestrus—metoestrus level and greater than at dioestrus. [3H]Uridine incorporation into ribosomal RNA (r-RNA) of anterior hypothalamus and pituitary was also demonstrated by incubation for 4 h. Under these conditions there was no effect of androgenization on hypothalamic r-RNA, but the specific activity of pituitary r-RNA was greater than normal.
EXCRETION OF ANTIDIURETIC ACTIVITY IN THE URINE OF CATS AND RATS AFTER ADMINISTRATION OF THE SYNTHETIC HORMONOGEN, Nα-GLYCYL-GLYCYL-GLYCYL-[8-LYSINE]-VASOPRESSIN (TRIGLYCYLVASOPRESSIN)
Authors: KYNČL J. , RUDINGER J. 
Published: December 2008

SUMMARY
The rate of excretion of antidiuretic activity in the urine of anaesthetized, water-loaded cats and of rats with familial diabetes insipidus after injection of single doses of lysine vasopressin (LVP) and of the long-acting analogue Nα-glycyl-glycyl-glycyl-[8-lysine]-vasopressin (triglycylvasopressin) has been studied by assays in water-loaded rats.
The excreted antidiuretic material in all experiments resembled LVP and differed from triglycylvasopressin in the time course of the recorded response, the slope of the log dose—response relationship, and the index of persistence. The total antidiuretic activity excreted was a fraction of that of the injected LVP but equalled or exceeded the assayable activity of the dose of triglycylvasopressin injected.
It is concluded that the excreted antidiuretic activity is due to LVP and that the excreted hormone originates from the triglycylvasopressin by enzymic activation in vivo.