bluuebunny/crossref_metadata_2025_split huggingface dataset:
LOCATION OF l-IDITOL: NAD OXIDOREDUCTASE (d-SORBITOL TETRAZOLIUM REDUCTASE OR KETOSE-REDUCTASE) IN THE GENITAL TRACT OF THE BULL
Authors: GERMINO N. I. , MICUCCI M. , GRAU V. , RAMA F. , CASTELLANO M. A. 
Published: December 2008

SUMMARY
The histochemical technique for the demonstration of the d-sorbitol dehydrogenase activity gave intensely positive results in the epithelium of the seminal vesicles and the glands of the ampulla of the ductus deferens of the bull. The enzymic activity was lower in the prostatic epithelium of the ductus deferens and the epididymis. The reaction was negative in the epithelium of the bulbo-urethral glands of Cowper.
The enzymic activity detected is connected with the synthesis of fructose, but in organs with a low concentration of fructose, such as the prostate gland and the ductus epididymidis the presence of the enzyme may be connected with the synthesis of sorbitol, also present in the semen.
In the seminal vesicles d-sorbitol dehydrogenase activity was found in the epithelium of the glandular tubules and in the material contained in those tubules. Using this technique, we have observed in the epithelium different types of cells which may correspond to different stages of a secretory cycle. The cells with greater deposits of diformazan appear to be related to the secretion of a product with enzymic activity.
OESTROGEN AND PROGESTERONE AND THE FUNCTION OF THE CORPORA LUTEA IN THE GUINEA-PIG
Authors: BLAND K. P. , DONOVAN B. T. 
Published: December 2008

SUMMARY
Regression of the corpora lutea in the guinea-pig could be accelerated by treatment with 10 μg. oestradiol benzoate daily over days 3–11 of the oestrous cycle. A single injection of 10 μg. oestradiol benzoate on day 3 was also effective. The luteolytic effect of oestrogen was abolished by hysterectomy, indicating that the uterus is involved in the mediation of the response. Progesterone (5 mg. daily over days 3–11) enhanced the luteal regression brought about by the presence of two glass beads in one horn of the uterus, but did not affect luteal size in otherwise intact females. Treatment of guinea-pigs with 5 mg. progesterone daily over days 2–5 or 4–7 failed to alter the length of the oestrous cycle.
THE IDENTIFICATION OF STEROIDS
Authors: BROOKS C. J. W. , BROOKS R. V. , FOTHERBY K. , GRANT J. K. , KLOPPER A. , KLYNE W. 
Published: December 2008

SUMMARY
In this paper the problems of establishing the identity of a compound isolated from biological material with a steroid are outlined and discussed. The nature of evidence required for identification and some techniques for obtaining this are briefly considered. The importance of establishing the specificity of a method for the quantitative measurement of a steroid in a biological extract is emphasized.
PATHWAYS OF DEHYDROEPIANDROSTERONE SULPHATE BIOSYNTHESIS IN THE HUMAN FOETAL ADRENAL GLAND
Authors: COOKE B. A. , COWAN R. A. , TAYLOR PATRICIA D. 
Published: December 2008

SUMMARY
The pathways of dehydroepiandrosterone sulphate (DHAS) biosynthesis in adrenal glands from the human previable foetus have been investigated by incubating pregnenolone, 17 α-hydroxypregnenolone and pregnenolone sulphate with homogenates of this tissue for different periods of time. The steroids formed were identified and measured by reverse isotope dilution or by gas—liquid chromatography and mass spectrometry of their derivatives. The results obtained are consistent with a main pathway from pregnenolone to DHAS via non-sulphated intermediates, i.e. 17 α-hydroxypregnenolone and DHA. The rate of pregnenolone sulphate metabolism to DHAS via 17 α-hydroxypregnenolone sulphate was found to be very slow compared with the rapid metabolism of pregnenolone to DHAS. These results are discussed in relation to the availability and nature of DHAS precursors in vivo.
THE STIMULATION OF INSULIN RELEASE BY ESSENTIAL AMINO ACIDS FROM RABBIT PANCREAS IN VITRO
Authors: MILNER R. D. G. 
Published: December 2008

SUMMARY
Pieces of rabbit pancreas were incubated in vitro in an incubation medium containing no glucose or 1·5 mg. glucose/ml. In each of these conditions the effect on insulin release of each of the essential amino acids at 5 mm concentration was studied. Leucine was the only essential amino acid that stimulated insulin release to a level which reached statistical significance in an incubation medium containing no glucose. In medium containing 1·5 mg. glucose/ml., arginine, isoleucine, leucine and lysine stimulated insulin release and phenylalanine inhibited insulin release. Glucagon, theophylline or dibutyryl cyclic adenosine monophosphate stimulated insulin release significantly in the presence of leucine but not in the presence of arginine. Arginine stimulated insulin release in the presence of leucine. The results of these experiments characterize further the difference in the mechanism of action of leucine and arginine on the pancreatic β-cell and indicate possible explanations for results obtained in other species in vivo.
STEROID BIOSYNTHESIS BY HUMAN FOETAL ADRENALS INCUBATED IN VITRO WITH [4-14C]PROGESTERONE: CHANGES WITH GESTATIONAL AGE
Authors: MILNER A. JOSEPHINE , MILLS I. H. 
Published: December 2008

SUMMARY
Adrenals from foetuses of 13 to 27 weeks gestation were sliced and incubated with 5 μC of [4-14C]progesterone for 2 hr. The biosynthesis of cortisol, 11-deoxycortisol, androstenedione and 11β-hydroxyandrostenedione was estimated by reverse isotope dilution. Cortisol was the major product identified and the production of both cortisol and 11β-hydroxyandrostenedione increased with gestational age in approximate proportion to the increasing adrenal weight. The ratio of (cortisol plus 11-deoxycortisol) to (androstenedione plus 11β-hydroxyandrostenedione) was constant at 13, 16 and 27 weeks gestation. The production of cortisol and androstenedione from progesterone and from pregnenolone by adrenal tissue from a 27-week-old foetus is compared.
PIGEON CROP SAC-STIMULATING ACTIVITY IN THE PITUITARY OF THE FLOUNDER (PLEURONECTES FLESUS)
Authors: CHADWICK A. 
Published: December 2008

SUMMARY
The examination of a pigeon crop sac-stimulating hormone from flounder pituitaries by polyacrylamide gel electrophoresis is described. Elution of the proteins after electrophoretic separation permitted both the identification of the protein bands responsible for stimulating the crop and a comparison with the prolactin bands from rat and toad pituitaries, as well as from the pituitaries of several other species of fish. The nature of the crop-sac response is discussed and it is suggested that certain features, in particular the absence of fatty granules, indicate a difference between fish and tetrapod prolactin sufficient to warrant the adoption of an alternative name for the fish hormone.
THE EFFECT OF ANGIOTENSIN ON RAT INTESTINAL FLUID TRANSFER
Authors: DAVIES N. T. , MUNDAY K. A. , PARSONS B. J. 
Published: December 2008

SUMMARY
Fluid transfer by isolated everted sacs of rat jejunum, ileum and intact colon prepared from adrenalectomized-nephrectomized rats 48 h after operation was reduced when compared with that of sacs prepared from untreated controls (P < 0·001). Angiotensin at 10−10 g/ml significantly (P < 0·01) stimulated fluid transfer by intestinal sacs prepared from the adrenalectomized-nephrectomized rats; all three regions of gut were equally sensitive.
Fluid transfer was similarly reduced in stripped colon sacs prepared from adrenalectomized-nephrectomized rats. Angiotensin had a dose-dependent biphasic action on fluid transfer by stripped colon sacs: low concentrations (10−11 and 10−12 g/ml) stimulated (P < 0·05), whilst high concentrations (10−9 and 10−8 g/ml) inhibited fluid transfer (P < 0·01). Histological examination of the colon preparations showed that the stripping procedure removed the ganglia, indicating that both angiotensin effects were due to direct action on the colon mucosa.
The significance of these results is discussed in relation to the role of angiotensin in the control of salt and fluid transport by the mammalian kidney and other epithelial tissues.
DEMONSTRATION OF MAMMOTROPHIC ACTIVITY OF THE MOUSE PLACENTA IN ORGAN CULTURE AND BY TRANSPLANTATION
Authors: KOHMOTO K. , BERN H. A. 
Published: December 2008

SUMMARY
Mammotrophic (i.e. mammogenic and/or lactogenic) activity of mouse placentae of different stages (4–19 days of pregnancy) was examined using organ co-culture of placental explants with mammary tissue. The test mammary tissues were taken from midpregnant (11–12 days) nulliparous A/Crgl mice and cultured in a synthetic medium (Waymouth's) supplemented with insulin (5 μg/ml) and aldosterone (1 μg/ml). The responses of mammary gland to placental explants were judged histologically, and were compared with those seen after the addition of ovine prolactin (5 μg/ml). With placentae from 6- to 19-day pregnant animals, distinct mammotrophic activity was seen, with the appearance of eosinophilic secretion in the mammary alveolar lumina, whereas with 4- or 5-day-old 'placentae', no mammotrophic activity was detected. Inasmuch as growth hormone does not substitute for prolactin in mammary gland development and function in the A/Crgl mouse, it can be concluded that a prolactin-like factor is present in the mouse placenta. The influence of placentae on mammary gland was further analysed by transplantation of placental fragments to mammary fat pads. Local lobuloalveolar development was prominent in some instances in the area around the placental transplants.
THE EFFECT OF SALT LOADING ON THE PITUITARY PROLACTIN LEVELS OF THE DOMESTIC DUCK (ANAS PLATYRHYNCHOS) AND JUVENILE HERRING OR LESSER BLACK-BACKED GULLS (LARUS ARGENTATUS OR LARUS FUSCUS)
Authors: ENSOR D. M. , PHILLIPS J. G. 
Published: December 2008

SUMMARY
The pituitary prolactin levels were measured in the domestic duck (Anas platyrhynchos) and in juvenile gulls from a mixed population of herring and lesser black-backed gulls. In the domestic duck the pituitary prolactin levels increased on the 2nd and 3rd days of maintenance on 0·3 m-NaCl, but by the 5th day they had fallen appreciably below the control levels. Maintenance of gulls with 0·3 m-NaCl produced no change in pituitary prolactin levels after 5 days, but a marked fall in prolaction levels when the birds were maintained on 0·7 m-NaCl for 5 days. This difference in response between the two species may be related to their degree of adaptation to a marine environment.
THE RESPONSE OF PLASMA SUGAR, FREE FATTY ACIDS, 11-HYDROXYCORTICOSTEROIDS AND GROWTH HORMONE TO INSULIN-INDUCED HYPOGLYCAEMIA AND VASOPRESSIN IN PRIMARY MYXOEDEMA
Authors: VINCE F. P. , BOUCHER BARBARA J. , COHEN R. D. , GODFREY JEAN 
Published: December 2008

SUMMARY
The plasma sugar, free fatty acids (FFA), 11-hydroxycorticosteroids (11-OHCS) and growth hormone (GH) response to insulin-induced hypoglycaemia, have been studied in 19 patients with primary myxoedema and 13 normal subjects. Nine of the myxoedematous patients were restudied after treatment. The plasma 11-OHCS response to lysine vasopressin (LVP) was studied in the myxoedematous subjects and again in eight of them after treatment.
In myxoedema the plasma sugar falls to a lesser extent and more slowly in response to insulin than normal and takes longer to recover. The fall in plasma FFA is not different from normal, but recovery of plasma FFA is delayed. The responses to insulin-induced hypoglycaemia of plasma GH and 11-OHCS may be smaller than normal in myxoedema and tend to improve on treatment. Altered GH and 11-OHCS responses to insulin-induced hypoglycaemia in myxoedema are not necessarily due to pituitary or hypothalamic dysfunction. No difference was found in the response of plasma 11-OHCS to LVP before and after treatment. Pituitary function cannot be fully assessed in the presence of hypothyroidism.
CHANGES IN ENZYMIC ACTIVITY, CHEMICAL COMPOSITION AND HISTOLOGY OF THE MAMMARY GLANDS AND METABOLITES IN THE BLOOD OF LACTATING RABBITS AFTER HYPOPHYSECTOMY AND REPLACEMENT THERAPY WITH SHEEP PROLACTIN, HUMAN GROWTH HORMONE OR BOVINE GROWTH HORMONE
Authors: HARTMANN P. E. , COWIE A. T. , HOSKING ZENA D. 
Published: December 2008

SUMMARY
Five groups of five lactating rabbits each were used. Milk yield was recorded from the 8th day of lactation onwards and on the 10th day of lactation the rabbits received the following treatments: Group S, sham-operation with saline (1 ml/12 h); Group P, hypophysectomy with sheep prolactin (1 mg/12 h); Group H, hypophysectomy with human growth hormone (1 mg/12 h); Group B, hypophysectomy with bovine growth hormone (1 mg/12 h) and Group C, hypophysectomy with saline (1 ml/12 h). The injections of saline or hormones were continued for 5 days and at the end of this period a blood sample was taken, the animals were killed and their mammary glands removed for histological examination and assay of the following enzymes: 6-phosphogluconate dehydrogenase (EC 1.1.1.44), phosphofructokinase (EC 2.7.1.11), phosphoglucomutase (EC 2.7.5.1), UDP-glucose pyrophosphorylase (EC 2.7.7.9), acetyl-CoA carboxylase (EC 6.4.1.2), acetyl-CoA synthetase (EC 6.2.1.1) and ATP-citrate lyase (EC 4.1.3.8). On the 5th day after surgery the concentrations of blood l-lactate and pyruvate and plasma free fatty acids and protein were similar in all groups, whereas plasma glucose was higher in groups S, B and H than in groups P and C. Although the weights of pituitary target organs (adrenals, thyroid and ovaries) were similar in all groups, the weights (g/kg body weight) of mammary tissue varied markedly, group S being the heaviest and group C the lightest. Milk yields, 5 days after surgery, for groups P and H were about 50% that for S, whereas those for B and C were 15 and 4% respectively. Where possible the enzyme activity was expressed as a ratio of the rate of synthesis of the end product of the pathway in which the enzyme occurred. With the exception of acetyl-CoA carboxylase which may have had a rate-limiting role in the synthesis of milk fat, enzymic activity in vitro was in excess of that required in vivo for the synthesis of either milk fat or lactose. It appeared that the rate of milk synthesis depended upon the degree of maintenance of the secretory epithelial cells within the mammary gland rather than a block in the synthetic pathways within these cells.
RELATIONSHIP BETWEEN INSULIN CONCENTRATIONS IN PLASMA AND PANCREAS OF FOETAL AND WEANLING RATS
Authors: BLÁZQUEZ E. , MONTOYA E. , QUIJADA CLEMENTE LÓPEZ 
Published: December 2008

SUMMARY
During the third part of pregnancy in the rat the concentrations of plasma insulin and tissue glycogen in the foetus increase progressively. These levels and the release of insulin by pancreas incubated in vitro were significantly higher than the values found in adult non-pregnant rats. After birth the correlation between plasma insulin concentration and the stores of glycogen was also evident. In the first day of life, the concentrations of plasma insulin, glycogen in liver, striated muscle and kidney decreased significantly; these values decrease even more during the first 15 days of lactation. After weaning started (20 days post partum), rapid increases of insulin and glycogen were observed, parallel to the slow growth of the newborn rat during the first 15 days of life and the more rapid rate of growth after 20 days. Similarly, the insulin content of the pancreas increased more significantly during the period in which pancreatic weight and plasma insulin concentrations increased more slowly. These results show that when plasma insulin concentrations increase, body growth and stores of glycogen are higher, suggesting an anabolic role of insulin in the foetal and newborn rat.
PROLACTIN—THYROID INTERACTION IN THE NEWT, DIEMICTYLUS VIRIDESCENS
Authors: GONA A. G. , PEARLMAN T. , ETKIN W. 
Published: December 2008

SUMMARY
Prolactin—thyroid interaction was analysed in the second metamorphosis of Diemictylus viridescens. Intraperitoneal injections of either 3 μg thyroxine (T4) or 0·2 mg propylthiouracil (PTU) on alternate days failed to induce second metamorphosis in the red eft (land stage); 0·1 mg PTU inhibited prolactin-induced second metamorphosis. The effect of prolactin was facilitated by 0·1 μg T4. However, 0·5 μg T4 inhibited water-drive behaviour after initial stimulation of integumentary changes and water-drive. Larger doses of T4 (1–3 μg) proved fatal to the efts when given together with 0·5–40 μg prolactin.
The results indicate that a certain optimal level of thyroid hormone is needed for the initiation of second metamorphosis. Nevertheless, prolactin—thyroid antagonism, previously reported in tadpoles, also occurs in the newt. Second metamorphosis appears to be brought about by a reversal of the low prolactin—high thyroid level of the eft phase to a high prolactin—low thyroid level.
UTERINE AUTOTRANSPLANTATION TO THE ABDOMINAL WALL IN THE GUINEA-PIG
Authors: BLAND K. P. 
Published: December 2008

SUMMARY
A method for autotransplantation of the uterus of the guinea-pig to the abdominal wall is described. Complete uterine autotransplantation by this method caused extended oestrous cycles (mean 24·67 days). Similar transplantation but without disconnexion of the cervical end of the uterus gave rise to cycles of similar length (mean 24·75 days) but transplantation without disconnexion of the tubal ends allowed the occurrence of normal cycles (mean 16·20 days). The site of metabolism of the uterine luteolytic factor is discussed.
DAILY RHYTHM OF PLASMA TYROSINE IN FASTING SUBJECTS
Authors: CAVAGNINI F. , LITTA-MODIGNANI R. 
Published: December 2008

SUMMARY
The daily rhythm of plasma tyrosine was studied in obese subjects during total fasting, because of the relative constancy of the metabolic processes in this state. The plasma levels of tyrosine showed circadian fluctuations which were similar, although less pronounced, to those observed by other authors. The lowest values occurred at 03.00 h and the highest at 08.00 h with a second rise at 19.00 h.
ISOLATION OF RADIOACTIVE OXYTOCIN AND VASOPRESSIN FROM THE POSTERIOR PITUITARY GLAND OF THE RAT AFTER THE INJECTION OF LABELLED TYROSINE INTO THE CEREBROSPINAL FLUID
Authors: PICKERING B. T. , JONES C. W. 
Published: December 2008

SUMMARY
A method is described for the preparation of isotopically pure [3H]oxytocin and [3H]vasopressin from the pooled posterior pituitary glands of groups of four or five rats after the intracisternal injection of [3H]tyrosine. Hormones were separated from deproteinized neurohypophysial extracts by chromatography on Amberlite CG-50, and further purified by chromatography on carboxymethylcellulose. In this way, samples of the hormones were obtained with a very high degree of isotopic purity. The method is suitable for studying the effects of stimuli to the hypothalamo—neurohypophysial system on the biosynthesis and transport of the hormones.
ELIMINATION OF THE FERGUSON REFLEX BY SECTION OF THE PELVIC NERVES IN THE LACTATING GOAT
Authors: PEETERS G. , de VOS N. , HOUVENAGHEL A. 
Published: December 2008

SUMMARY
Distension of the vagina by an inflated balloon induces milk ejection in goats. This reflex (the Ferguson reflex) is based on a neurohormonal mechanism. In three goats the reflex was abolished after bilateral section of the complex pelvic nerves plus caudal rectal nerves. Bilateral section of the pelvic nerves only, caused a complete elimination of the reflex in 11 out of 13 goats; in the two remaining animals, the reflex was abolished after a supplementary section of the pudendal nerve plus caudal rectal nerves. The reflex remained intact in one goat in which first the caudal rectal nerves and subsequently the pudendal nerve were cut. Elimination of the Ferguson reflex was accompanied by a marked reduction of the intensity of straining movements which are normally induced by distension of the vagina. Bilateral section of the pelvic nerves provoked a severe but temporary paralysis of the large intestine with blocking of the defaecation reflex. It is suggested that in ruminants the afferent pelvic nerves are involved in the release of oxytocin and in the intense straining occurring during the phase of expulsion at parturition.
4-THREONINE ANALOGUES OF NEUROHYPOPHYSIAL HORMONES WITH SELECTIVELY ENHANCED OXYTOCIN-LIKE ACTIVITIES
Authors: SAWYER W. H. , MANNING M. 
Published: December 2008

SUMMARY
The 4-threonine analogues of oxytocin and of mesotocin and isotocin were prepared by solid-phase synthesis. [4-Threonine]-oxytocin is about twice as active as oxytocin in rat uterus assays in vitro and in vivo and about three times as active in fowl vasodepressor assays. It is slightly more active than oxytocin in rat or rabbit milk-ejection assays. When infused intravenously into water-loaded rats it causes much less depression of diuresis than does an equal dose of oxytocin. [4-Threonine]-oxytocin has much less vasopressor activity than oxytocin. [4-Threonine]-mesotocin also shows enhanced oxytocin-like properties. Its oxytocic activity is equal to or greater than that of oxytocin and its fowl vasodepressor potency is about the same as that of [4-threonine]-oxytocin, 1500 u./mg. It also has less antidiuretic and vasopressor activities than mesotocin. Thus 4-threonine analogues, containing nothing but common l-amino acids, appear to have more of the specific oxytocin-like properties and less of the vasopressin-like properties than do oxytocin or mesotocin. Thus they may be considered improvements on the natural hormones. In this respect they are unique among the reported synthetic analogues of natural peptide hormones.
Substitution of 4-threonine in the weakly-active analogue [3-leucine]-oxytocin also increases its oxytocic and fowl vasodepressor activities. Thus a threonine in the 4-position appears to endow oxytocin-like peptides with greater specific activities than do the amino acids that occur naturally in this position, glutamine and serine. These observations may be of interest when considered (a) from an evolutionary viewpoint, (b) in attempting to interpret relations between molecular structures and biological activities, and (c) as describing peptides with more of the desired properties of oxytocin and less of the undesired properties which might have therapeutic advantages over the natural hormone.
THE ACTION OF ADRENOCORTICOTROPHIN ON THE FREE NUCLEOTIDE POOL AND RNA SYNTHESIS IN RAT ADRENALS AND LIVER
Authors: BOYADJIEV S. I. , HADJIOLOV A. A. 
Published: December 2008

SUMMARY
The action of adrenocorticotrophin (ACTH) in vivo on the amount and [32P]phosphate labelling of free adenine nucleotides and RNA of rat liver and adrenals was studied. Treatment with ACTH did not alter the total amount of free adenine nucleotides. In both the liver and adrenals the amount of ATP decreased, while that of ADP and AMP increased. As a result a more than twofold decrease of the ATP: ADP + AMP ratio was caused by ACTH. This effect was observed 2 h after ACTH administration and remained unchanged up to the 24th hour.
Three hours after [32P]phosphate administration, the labelling of the α-phosphate of free adenine nucleotides in liver was more than five times higher than that in the adrenals. After 24 h of treatment with ACTH the incorporation of [32P]phosphate into free adenine nucleotides of the adrenal was decreased, while that of liver was increased.
The labelling of the high-molecular weight RNA of the adrenals and liver was of the same order. A similar correlation was found when the labelling of AMP obtained from RNA by snake venom phosphodiesterase hydrolysis was compared. Treatment with ACTH decreased the labelling of RNA in the adrenals, while the labelling of RNA in liver was increased. The changes in the labelling of RNA in both organs reflect the variations in the labelling of free adenine nucleotides.
The results are discussed and it is suggested that ACTH treatment in vivo affects the amount and the turnover of free nucleotides in the adrenals and liver. The variations in RNA labelling are secondary and reflect the turnover of the free nucleotides.