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Kennedy T G - - 1975
Hypophysectomized-ovariectomized mice receiving oestrogen and progesterone were treated with and without bovine prolactin and growth hormone (GH). Prolactin significantly increased vaginal weight and vaginal sialic acid content, but had no effect on vaginal sialic acid concentration, an indicator of vaginal mucification. Growth hormone significantly increased all three vaginal parameters. For ...
Kjeld J M - - 1975
High specific activity [125-I] triiodothyronine and [125-I] thyroxine have been produced regularly by the chloramine T radioiodination method. Simultaneous production of [125-I] triiodothyronine and [125-I] thyroxine is usual when diiodothyronine or triiodothyronine are employed as the starting materials. Specific activities reached vary with the starting compound (diiodothyronine, triiodothyronine, thyroxine) used, ...
Tobe S S - - 1975
1. Radiochemical in vitro assays show that there are large and rapid changes in the spontaneous rate of juvenile hormone synthesis and release during the course of sexual maturation in the locust. 2. Parallel observations on glands incubated with farnesenic acid show that the rate-limiting step is always prior to ...
Symons C - - 1975
Severe cardiac hypertrophy has been produced experimentally in rats by long-term, low-dose treatment with tri-iodothyroacetic acid. The dose used was insufficient to cause any apparent systemic or metabolic effect. It is suggested that similar iodinated substances in the blood in man, resulting from normal or abnormal thyroid hormone catabolism, may ...
Epand R M - - 1975
Trinitrophenyl groups have been specifically introduced into the alpha- and/or the epsilon-NH2 groups of glucagon by reaction with trinitrobenzenesulfonic acid. Introduction of this group into the epsilon-NH2 position of the hormone leads to an apparant increase in the helical content as measured by circular dichroism, while substitution on the alpha-NH2 ...
Speake B K - - 1975
1. Explants of mammary gland from mid-pregnant rabbits were cultured with insulin, prolactin and cortisol. 2. Antibodies raised to fatty acid synthetase were used to measure the amount as well as the rate of synthesis and the rate of degradation of the enzyme in the explants over defined periods in ...
Martínez-Honduvilla C J - - 1975
Treatment of intact pine seeds with plant hormones and steroid substances for several days, after an initial 24 hour immersion in different hormone solutions, resulted in a substantial increase in the specific activity of isocitrate lyase and malate dehydrogenase than the observed in the corresponding control solutions. Fresh weights did ...
Goldfine I D - - 1975
L-Triiodothyronine in vitro increased the uptake of the non-metabolizable amino acid, alpha-aminoisobutyrate, into isolated rat thymocytes. This effect was evident at extracellular free hormone concentrations of 10-7 to 5 times 10-8M and was due to a marked inhibition of amino acid efflux. In contrast, insulin and dibutyryl cyclic AMP, which ...
Drezner M K - - 1975
The effects of growth hormone-dependent serum factors on amino acid transport and on cartilage cyclic AMP levels in embryonic chicken cartilage were studied in vitro. Cartilages incubated in medium containing rat serum showed a significantly greater uptake of alpha-amino [1-14C] isobutyrate or [1-14C] cycloleucine than control cartilages incubated in medium ...
Jefferson L S - - 1975
The effects of growth hormone, administered in vivo or added in vitro, on amino acid transport and utilization have been studied in perfused livers of normal and hypophysectomized rats. A perfusion system employing a nonrecirculating medium was used in all of the studies. Two nonmetalbolizable amino acid analogues, alpha-aminoisobutyric acid ...
Nieuwenhuis M - - 1975
Sex specificity is observed in mating types of the fungus Oucor mucedo with respect to the production of 4-hydroxy methltrisporates (plus mating type) and trisporins (minus mating type), and in the conversion of these metabolites to trisporic acids by the mating partner. These compounds induce zygophores on the opposite mating ...
Fawcett C P - - 1975
The luteinizing hormone (LH) and follicle stimulating hormone (FSH) releasing activity, as well as the prolactin (PRL) release-inhibiting activity were measured in both neutral aqueous, and acid ethanolic extracts of rat hypothalami. LH and FSH-releasing activities were detectable only in the latter type of extract, whereas PRL release-inhibiting activity appeared ...
Nilsson L - - 1975
It has earlier been reported from this laboratory that FSH can stimulate amino acid uptake, protein synthesis and glycolysis in the isolated prepubertal rat ovary. In the present investigation to the effects of LH and HCG were studied. The hormones were injected to prepubertal female rats, and the ovaries were ...
Leonard B E - - 1975
The formation of dansyl derivatives of amino acids, 5-hydroxyindoleacetic acid and histamine, and their separation on polyamide plates provided a reliable and sensitive method for studying circadian changes in single pineal and pituitary glands of the rat. There appears to be no correlation between the circadian changes in concentrations of ...
Sondheimer E - - 1974
Embryos from dormant and stratified Fraxinus americana seed were incubated with (S)-2-(14)C-abscisic acid (ABA) under a variety of conditions. Both dormant and stratified embryos rapidly metabolize abscisic acid to phaseic acid, dihydrophaseic acid, and an unidentified polar metabolite apparently derived from dihydrophaseic acid. Although the stratified embryos may have an ...
Tobe S S - - 1974
The rate at which isolated corpora allata of adult female Schistocerca gregaria incorporate [(3)H]farnesenic acid and [(14)C]methionine into C(16)juvenile hormone in vitro was examined at different concentrations of farnesenic acid, methionine, O(2) and H(+) ions. Maximum juvenile hormone biosynthesis is obtained at a farnesenic acid concentration of 20mum. The range ...
Pagliara A S - - 1974
Interactions between glucose and arginine and a mixture of 20 amino acids found in normal rat serum were studied in the isolated perfused rat pancreas of normal rats, with release of immunoreactive glucagon and insulin as parameters. Secretion of both pancreatic hormones was low during the steady state, whether glucose ...
Li C H - - 1974
Two biologically active fragments have been isolated from plasmic digests of human pituitary growth hormone. It was shown that these two fragments were derived from the cleavage of the Arg-Thr (positions 134-135) and the Lys-Gln (positions 140-141) bonds of the hormone: one has 134 amino acids and the other 51 ...
Abramow M - - 1974
Effects of the diuretic ethacrynic acid on osmotic water permeability were investigated in the isolated perfused collecting tubule of the rabbit kidney. The base-line water permeability of the collecting tubule was not affected when the drug (10(-4)M) alone was added to the bathing medium. Vasopressin alone in the bathing medium ...
Rubecz I - - 1974
The metabolic and hormonal effects of a short term (24-36 hrs), alternating intravenous administration of hypertonic (16%) glucose and Aminosol-glucose were investigated in premature infants. The majority of the infants under 1 500 g showed pathological signs and did not tolerate oral feeding. The purpose of the study was to ...
Blaquier J A - - 1974
Rat epididymal tubules maintained in organ culture for 3 or 7 days in media containing androgen showed a marked increase in the incorporation of radioactive amino acids and uridine into acid insoluble material. When the tubules were exposed to these hormones for brief periods, the incorporation of precursors was inhibited ...
Chu L L - - 1973
Human parathyroid glands obtained at autopsy were incubated with [(3)H]leucine and [(3)H]lysine. After incubation, nonradioactive parathyroid tissue of either human or bovine origin was added. Radioactive parathyroid hormone and proparathyroid hormone were isolated from the gland and medium by organic solvent and salt fractionation, trichloroacetic acid precipitation, Sephadex G-100 gel ...
Jones R L - - 1973
The release of potassium, magnesium, and phosphate ions from aleurone cells of barley (Hordeum vulgare L. cv. Himalaya) is a gibberellic acid-dependent process. The release of these ions is preceded by a lag period of 6 to 8 hours after gibberellic acid addition. The effect of gibberellic acid on the ...
Coombe B G - - 1973
Berries on field-grown Vitis vinifera cv. Doradillo were treated at different times during stage II with benzothiazole-2-oxyacetic acid or 2-chloroethylphosphonic acid, and measurements were made of their growth and hormone content. The concentration of ethylene was low during stage II and declined as berries ripened. Both 2-chloroethylphosphonic acid and benzothiazole-2-oxyacetic ...
Beasley C A - - 1973
Exogenous plant growth regulators can substitute for pollination, fertilization, and subsequent embryo development in cotton. Isolated, unfertilized, immature ovules enlarge in the presence of kinetin, and both enlarge and produce fibers in the presence of indoleacetic acid or gibberellic acid or both. An extract of germinating cotton pollen qualitatively mimics ...
Tanada T - - 1973
The phytochrome-mediated attachment of mung bean (Phaseolus vulgaris L., var. Oklahoma 612) root tips on glass is quickly affected by indoleactic acid and abscisic acid at concentrations of 10 nm or less. Indoleacetic acid induces detachment, whereas abscisic acid induces attachment. Both plant regulators rapidly antagonize the action of the ...
Gaspar T - - 1973
Detachment of the cotyledons from the lentil (Lens culinaris Med.) embryonic axis causes in the latter an increase in total peroxidase activity which is shown to be due to enhancement of specific cathodic isoperoxidases. Kinetin treatment of attached or detached axes promotes activity of essentially the same cathodic isoperoxidases. In ...
Tanada T - - 1973
The effects of low concentrations (10 nm or less) of indoleacetic acid and abscisic acid on the phytochrome-mediated attachment of barley root (Hordeum vulgare L., var. Compana) tips on glass have been found to be opposite to those reported for mung bean root tips. Unlike their effects on mung bean ...
Mayak S - - 1972
The role of abscisic acid and ethylene in the senescence of rose petals cv. Golden-Wave was examined. A rise in ethylene evolution, followed by an increase in the level of abscisic acid was observed. The presence of abscisic acid in rose petals was established, using different chromatography systems, several bioassays, ...
Fernlund P - - 1972
The blanching hormone of the prawn, Pandalus borealis, is pGlu-Leu-Asn-Phe-Ser-Pro-Gly-Trp-NH(2). Its structure was settled by a combination of mass spectrometry and Edman-dansyl analysis of a thermolysin fragment. Confirmation of the structure was obtained by chemical synthesis from amino acids. This neurosecreted hormone is active in picogram amounts when tested in ...
Walter R - - 1972
Starting with assignments of proton nuclear magnetic resonance previously made for oxytocin in deuterated dimethylsulfoxide at 220 MHz, we have assigned resonances for the mammalian antidiuretic hormone, lysine vasopressin. The results demonstrate that spectral assignments of neurohypophyseal hormones and their congeners can, within certain limits, be derived from each other. ...
Hruby V J - - 1972
Tocinamide and tocinoic acid, ring structures of oxytocin, are potent inhibitors of the release of melanophore stimulating hormone from the rat and hamster pituitary in vitro. Tocinamide is effective at concentrations as low as 10-(14)M on the mammalian pituitary. These peptides do not affect release of the hormone on the ...
Kriedemann P E - - 1972
The closure of stomata by abscisic acid was examined in several species of plants through measurements of CO(2) and H(2)O exchange by the leaf. The onset of closure was very rapid, beginning at 3 minutes from the time of abscisic acid application to the cut base of the leaf of ...
Kemper B - - 1972
Biosynthesis of a precursor to bovine parathyroid hormone has been demonstrated in slices of parathyroid tissue incubated in vitro. The proparathyroid hormone is 15-20 amino acids larger than the bovine hormone, and has a molecular weight of about 11,500 as determined by polyacrylamide gel electrophoresis. Upon incubation of parathyroid slices ...
Reeds P J - - 1971
The separate effects of insulin and growth hormone on the uptake and incorporation of five amino acids into diaphragm muscle from non-hypophysectomized rabbits has been examined. Both growth hormone and insulin, when present in the medium separately, stimulated the incorporation into protein of the amino acids, leucine, arginine, valine, lysine ...
Meyer A S - - 1971
The absolute configuration of the predominant Cecropia hormone, methyl 12,14-dihomojuvenate, has been determined to be methyl (E,E)-(10R,11S)-(+)-10,11-epoxy-7-ethyl-3,11-dimethyl-2, 6-tridecadienoate (I). The less abundant hormone, methyl 12-homojuvenate, can be presumed by analogy to have the corresponding 3,7,11-trimethyldienoate structure (II). The assignment has been established with microamounts of substance by applying Horeau's method ...
Li C H - - 1971
The complete amino acid sequence of the human chorionic somatomammotropin molecule been proposed; and then compared with that of human growth hormone and ovine lactogenic hormone.
Shih C Y - - 1971
Using the electron microscope, we compared the effects of abscisic acid and gibberellin A(3) on excised buds from resting potato (Solanum tuberosum L.) tubers. Cells of abscisic acid-treated buds became progressively more vacuolated during a 12-hour time course study as compared with control (water) and gibberellin A(3)-treated buds. Concentric configurations ...
Mitnick M - - 1971
Biosynthesis of thyrotropin-releasing hormone (L-pyroglutamyl-L-histidyl-L-proline amide) in vitro was studied. Rat hypothalamic fragments were incubated in Krebs-Ringer bicarbonate buffer that contained either (14)C-labeled proline, histidine, or glutamic acid (the three probable precursor amino acids,) and for control purposes each of 16 other naturally occurring amino acids. A number of labeled ...
Brewer H B HB - - 1970
Bovine parathyroid hormone has been isolated in homogeneous form, and its complete amino acid sequence determined. The bovine hormone is a single chain, 84 amino acids long. It contains amino-terminal alanine, and carboxyl-terminal glutamine. The bovine parathyroid hormone is approximately three times the length of the newly discovered hormone, thyrocalcitonin, ...
Snyder L M - - 1970
Normal erythrocytes, when incubated with thyroid hormone, were found to have increased levels of 2,3-diphosphoglyceric acid. In addition, a partially purified enzyme preparation, when incubated with either a 1,3-diphosphoglyceric acid generating system or 1,3-diphosphoglyceric acid directly, showed increased levels of 2,3-diphosphoglyceric acid when exposed to thyroid hormone. The hormonal effect ...
Clemens M J - - 1970
1. Incorporation of [(14)C]leucine into protein in rat liver slices, incubated in vitro, increased as the concentration of unlabelled amino acids in the incubation medium was raised. A plateau of incorporation was reached when the amino acid concentration was 6 times that present in rat plasma. Labelling of RNA by ...
Snyder L M - - 1970
A biphasic thyroid hormonal effect has been shown on 2,3-diphosphoglyceric acid synthesis in a crude enzyme, hemoglobin-free preparation from normal human erythrocytes.
Yotis W W - - 1970
Diethylstilbestrol (DS) has been shown to be active against staphylococci and other gram-positive bacteria but not against gram-negative microorganisms. The present study extends these findings. Standardized suspensions of (14)C-labeled Staphylococcus aureus serotypes III and IV and Shigella flexneri were prepared and exposed to pharmacological concentrations of DS (1 to 20 ...
Gomez, Francisco Enrique.
Thesis (Ph. D.)--University of Wisconsin--Madison, 2003.
Dubois E A - - 2002
Gonadotropin-releasing hormone (GnRH) is the neuropeptide that links the brain to the reproductive system. Most vertebrate species express two forms of GnRH, which differ in amino acid sequence, localization, distribution, and embryological origin. The GnRH system in the ventral forebrain produces a species-specific GnRH form and projects toward the gonadotropic ...
Jarrett R J - - 1969
In two subjects concurrent infusion of amino-acids and the hormones secretin and pancreozymin provoked much higher plasma insulin levels than did administration of amino-acids or hormones individually. It is suggested that this may be a physiological phenomenon, augmenting the release of insulin from the pancreas after a meal containing protein.
Kennedy J F - - 1969
A preparation of human pituitary follicle-stimulating hormone was subjected to periodate oxidation, borohydride reduction and acid hydrolysis. Comparison of the analysis of the remaining intact carbohydrate and amino acid units with the analyses of the original material and identification of the carbohydrate fragments permit some structural assignments to the molecule ...
Lips S H - - 1969
Suitable concentrations of kinetin and gibberellic acid permit induction of nitrate reductase in leaves of tobacco in the dark. Hormone sprays eliminate the need for light induction of the enzyme. The concentration of gibberellic acid required for optimal induction varies according to the concentration of kinetin supplied.
Kafka M S - - 1969
Insulin in low concentrations inhibits the uptake of Ca(++) by the monooctadecyl (stearyl) phosphate monolayer (at air-water interface) and facilitates the release of Ca(++) adsorbed to the monolayer. These effects of insulin are more pronounced at higher insulin concentrations. Evidence is presented that a relatively intact insulin molecule competes with ...
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