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Clejan S - - 1986
Effects of growth hormone on phospholipid composition and fatty acyl distribution were studied in liver mitochondria of hypophysectomized rats. After hypophysectomy, only cardiolipin showed a 25% decrease. Its fatty acyl distribution, which consisted mainly of linoleic acid (55-60%) and oleic acid (20%), was unchanged. In phosphatidylcholine and phosphatidylethanolamine fractions the ...
Havel H A - - 1986
Previous investigations have shown that bovine growth hormone (bGH, somatotropin) unfolds through a reversible multistate process with at least one stable equilibrium intermediate. In extending our knowledge of the folding process for bGH, we demonstrate that a self-associated form of partially denatured bGH is formed during equilibrium unfolding experiments. The ...
Tou J S - - 1986
The first twenty-nine amino acids of human Growth Hormone Releasing Factor (hGRF) possess a distinct amphiphilic character. This is seen as twisted hydrophobic and hydrophilic bands in the helical net projection. Four amidated analogs were designed by optimizing amphiphilic and helical potentials of the native sequence. These designed analogs, with ...
Szirtes T - - 1986
A new series of thyrotropin-releasing hormone (TRH) analogues, obtained by further modifications of our most potent central nervous system (CNS) stimulating neutral tripeptides at both termini, were synthesized by the pentafluorophenyl ester method and tested for CNS and thyrotropin (TSH) releasing activity. Replacement of pyroglutamic acid by pyro-2-aminoadipic acid, 2-oxoimidazolidine-4-carboxylic ...
Veliçelebi G - - 1986
A 29-amino acid analog of growth hormone releasing factor (GHRF) was designed in which the sequence of the first six amino acids at the amino terminus was maintained while the postulated amphiphilic helical structure in the remainder of the molecule was optimized. The amino acid sequence of the analog differed ...
Goodridge A G - - 1986
The activity of hepatic fatty acid synthase (EC 2.3.1.85) correlates positively with the rate of synthesis of long-chain fatty acids. Thus, in a starved chick, both the rate of fatty acid synthesis and the activity of fatty acid synthase are low. Feeding stimulates both processes. The increase in fatty acid ...
Meijer L - - 1986
Oocyte maturation (meiosis reinitiation) in starfish is induced by the natural hormone 1-methyladenine. In some species (group 2) oocyte maturation can be induced by micromolar concentrations of a few fatty acids such as arachidonic and eicosapentaenoic acids or by nanomolar concentrations of hydroxyeicosatetraenoic acid. Complete maturation is triggered: increased protein ...
Lang M A - - 1986
To characterize the V2 receptor (for antidiuretic hormone), we have studied the effect of a number of neurohypophysial hormone analogues on cyclic AMP (cAMP) accumulation and short-circuit current in cultured epithelia formed by A6 cells. A6 is the designation of a continuous cell line derived from the kidney of Xenopus ...
Maddaiah V T - - 1986
The time course of the effects of GH on state 3 respiration and fatty acid composition of liver mitochondria was investigated up to 48 h after an injection of bovine GH to hypophysectomized rats. The respiratory rate increased significantly by 12 h, whereas the docosahexaenoic acid level, the total unsaturation ...
Lanks K W - - 1986
A wide variety of agents other than heat have been reported to induce or suppress heat shock protein (hsp) synthesis in eukaryotic cells. Such agents, termed 'modulators', include inhibitors of respiration, low molecular weight nutrients, oxygen, hormones, sulfhydryl reagents, ionophores and amino acid analogues. The evidence for modulation is critically ...
Rooney S A - - 1986
Because of current interest in use of a combination of glucocorticoid and thyroid hormones for prevention of respiratory distress syndrome we examined the effects of dexamethasone and triiodothyronine (T3), alone and in combination, on glycogen content and rates of fatty acid and phosphatidylcholine synthesis in fetal rat lung. The hormones ...
Chan J S - - 1986
After initial purification of ovine placental lactogen (oPL) using the procedures described previously [(1976) Endocrinology 98, 65-75], the oPL preparation was further purified by high-performance liquid chromatography (HPLC) using an anionic exchange column (Bio-Sil TSK DEAE-2-SW). Two forms of oPL with different relative mobilities on HPLC were isolated and designated ...
Picard J Y - - 1986
Direct biochemical analysis has been applied to bovine testicular anti-Müllerian hormone (AMH), purified from incubation medium of bovine fetal testes by immunochromatography on a monoclonal antibody. The hormone contains a high proportion of hydrophobic amino acids and 13.5% carbohydrate. The oligosaccharide composition suggests that both N- and O-glycosidically linked chains ...
Nutt R F - - 1986
Cyclic hexapeptide analogs of somatostatin with insulin, glucagon, and growth hormone (GH) release inhibitory potencies of 50-200 times those of somatostatin have been synthesized. Replacement of the Phe-7 residue with histidine has resulted in increased oral bioavailability and duration of action. Metabolic degradation of L-Trp containing analogs upon oral administration ...
Fabris N - - 1986
The frequent association of malnutrition, infectious diseases and aging has stressed the role played by some nutrients on the immune efficiency and by nutrient supplementation on the age-dependent immunological decline. In the present paper there are reported evidences that oral administration of two amino acids--lysine and arginine--recovers, in old Balb/c ...
Schindelmeiser J - - 1986
The distribution of complex carbohydrates was studied in the testis of the European fire salamander, Salamandra salamandra, by light- and electron-microscopic methods. The basal laminae and fibrous structures in the connective tissue between the lobules are PAS-positive. After alcianblue staining (at pH = 2.8), acid mucopolysaccharides could be demonstrated in ...
Csaba G - - 1986
Histidine stimulates the phagocytosis of Tetrahymena to the same extent as histamine, and also stimulates its division, which histamine does not. Tyrosine and diiodotyrosine equally stimulate the growth of the Tetrahymena. Both amino acids inhibit the characteristic influence of the adequate amino acid hormone when added to Tetrahymena culture 72 ...
Alquier C - - 1985
Open thyroid follicles were prepared by mechanical disruption of pig thyroid fragments through a metal sieve. This procedure allowed preparation of thyroid-cell material depleted of colloid thyroglobulin. Open thyroid follicles were used to prepared a crude particulate fraction, which contained lysosomes, mitochondria and endoplasmic reticulum. These organelles were subfractionated by ...
Ji I - - 1985
The N-hydroxysuccinimide ester of 4-azidosalicylic acid, a photoactivable heterobifunctional reagent, can be radioiodinated. The low efficiency (3%) of the radioiodination by a previously published method (I. Ji and T. H. Ji, 1982, Anal. Biochem. 121, 286-289) has been increased to 63% by substituting the solvent, acetone, with others such as ...
Anderson R E - - 1985
Changes in the acidity of osteoclasts were evaluated by direct measurement of the fluorescent intensity of osteoclasts exposed to acridine orange, a fluorescent weak base which becomes concentrated in acid-containing subcellular compartments. Parathyroid hormone (PTH) produced dose-dependent increases in fluorescent intensity; maximal increases in intensity occurred at doses between 3 ...
Vázquez-Alcántara M A - - 1985
Diesters of 17 beta-estradiol using palmitic acid (16:0) and oleic acid (18:1, cis-9-Octadecenoic acid) have been synthesized for potential evaluation as long-acting compounds. Female castrated rats were injected 1 mumol of estradiol dipalmitate and estradiol dioleate, using estradiol benzoate and estradiol enanthate as controls. Biological activity was determined by uterine ...
Tajima K - - 1985
Using a perifusion system, we studied the effect of iopanoic acid, an iodinated contrast agent used in oral cholecystography, on the release of cAMP, T3, T4, and rT3 from perifused rat thyroid pieces. A 0.1 mg/ml iopanoic acid solution significantly inhibited the TSH-stimulated release of cAMP (without iopanoic acid, 8175 ...
Wernerman J - - 1985
Plasma concentrations of free amino acids have previously been found to decrease posttraumatically and this decrease can be reproduced by infusion of stress hormones. The mechanisms underlying this effect has not been investigated and therefore 14 healthy subjects were studied by infusing adrenaline alone or a combination of adrenaline, glucagon, ...
Meizel S - - 1985
This review deals with exogenous molecules that stimulate the acrosome reaction (AR) of mammalian sperm in vitro, presumably by acting at the sperm surface. Such molecules may exert their effect(s) by stimulating capacitation and/or by stimulation or initiation of the AR, and they are probably present at one of three ...
Denko C W - - 1985
Effects of hormonal peptides on inflammation were investigated in normal rats receiving injections of urate crystals into the hindpaw. Beta endorphin, somatostatin and alpha melanocyte stimulating hormone injected along with urate crystals produced diminished swelling. Neurotensin and substance P produced increased swelling. Intramuscular calcitonin inhibited inflammation. In rats made deficient ...
Nemeroff C B - - 1985
Bilateral intrahypothalamic injections of the brain metabolite quinolinic acid (QUIN) were made in an attempt to examine its effects on the secretion of LH, PRL, GH and TSH. Quin, a neuroexcitatory amino acid with close structural similarities to glutamate, kainate and N-methylaspartate, was infused into unanesthetized male rats, the animals ...
Wagner G F - - 1985
This report describes the isolation of growth hormone (GH) from the chum salmon (Oncorhynchus keta) pituitary using gel, affinity, and ion exchange chromatography. Chum GH has an estimated molecular weight of 23,500 and an amino acid composition that is consistent with a vertebrate GH. The differentially charged forms of chum ...
Yamashiro D - - 1985
Human insulin-like growth factor II (IGF-II) with 67 amino acids and three disulfide bridges has been synthesized by the solid-phase method. The synthetic hormone is shown to be homogeneous in high performance liquid chromatography (HPLC), high performance partition chromatography (HPPC), and chromatofocusing. It is indistinguishable from natural hormone in HPLC, ...
Chan R L - - 1985
Nafarelin acetate (less than Glu-His-Trp-Ser-Tyr-3-(2-naphthyl)-D-Ala-Leu-Arg-Pro-Gly-NH2) is a potent agonistic analogue of luteinizing hormone-releasing hormone. After a single iv administration of nafarelin acetate (with 14C label at C-3 of 3-(2-naphthyl)-D-Ala) to female rhesus monkeys, about 80% of the radioactivity was eliminated in urine. Five major radioactive urinary metabolites were isolated and ...
Fujibayashi S - - 1985
We reported recently the presence of somatostatin-like immunoreactivity (SLI) in the glomerulus of rat kidney. In the present study, we examined factors affecting SLI release from isolated rat glomeruli using a perifusion system. Perifusate containing a mixture of essential amino acids stimulated SLI release, while other hormonal agents such as ...
Sherwood N M - - 1985
The two living representatives of the most ancient vertebrates, Agnathans, are lamprey and hagfish. Using immunological methods, we identified gonadotropin-releasing hormone (GnRH)-like molecules in the lamprey brain, but not hagfish. The lamprey GnRH was detected poorly by antisera directed at the C-terminus, suggesting that a C-terminal amino acid substitution may ...
Yee J B - - 1985
The effect of an intraperitoneal injection of various hormones on the incorporation of amino acids and uridine into acid-precipitable material by subsequently isolated testicular macrophages was investigated. It was found that treatment with follicle-stimulating hormone (FSH), but not luteinizing hormone (LH) or insulin, significantly increased incorporation of amino acids into ...
Finn F M - - 1985
Biotinylated photoaffinity derivatives of adrenocorticotropin (ACTH) are potentially useful tools for the identification of ACTH receptors. The hormone can be attached covalently to its receptor by photoactivation, and the presence of biotin in the molecule facilitates isolation of the solubilized hormone-receptor complex on columns of immobilized succinoylavidin (Suc-avidin). Six photoprobes ...
Li C H - - 1985
Human insulin-like growth factor II with 67 amino acid residues and three disulfide bridges has been synthesized by the solid-phase method. Homogeneity of the synthetic product is ascertained by chromatofocusing, high performance liquid chromatography and amino acid analysis. In both radioimmunoassay and radioreceptor assay, the synthetic product is indistinguishable from ...
Katoh K - - 1985
The effects of acetylcholine, short-chain fatty acids and peptide hormones on membrane potential and input resistance of the pancreatic acinar cells of sheep were investigated using intracellular glass microelectrodes. The resting membrane potential and input resistance were -28.0 +/- 4.3 mV (mean +/- SD, inside negative, n = 23) and ...
Chauvet J - - 1985
The neurohypophyseal hormones of two South American opossums (Didelphis marsupialis and Philander opossum) were isolated by molecular sieving and preparative high-pressure liquid chromatography (HPLC). One oxytocin-like and two vasopressin-like peptides were found in each species. These peptides have been identified by their amino acid composition and by their retention time ...
Tanaka M - - 1985
The diurnal variation in lysosomal acid cholesteryl ester hydrolase (Acid CEH), (EC 3.1.1.13) has been examined in fed, fasted and adrenalectomized rats. The Acid CEH activity of normal rat liver exhibits a diurnal rhythm with maxima at 06.00 hours and minima at 18.00 hours, but such a rhythm was not ...
Dagogo-Jack S - - 1985
Epidermal growth factor (EGF) is a small polypeptide with potent mitogenic activity. Its synthesis by mouse submaxillary gland is stimulated by certain hormones. To assess its physiological significance in man, we have developed a homologous radioimmunoassay for human epidermal growth factor (hEGF) in saliva. A satisfactory standard curve was readily ...
Nagasawa H - - 1984
Three molecular forms of prothoracicotropic hormone were isolated from the head of the adult silkworm, Bombyx mori, and the amino acid sequence of 19 amino acid residues in the amino terminus of these prothoracicotropic hormones was determined. These residues exhibit significant homology with insulin and insulin-like growth factors.
King J A - - 1984
Studies on partially purified chicken hypothalamic luteinizing hormone releasing hormone (LHRH) utilizing chromatography, radioimmunoassay with region-specific antisera, enzymic inactivation, and chemical modification established that the peptide is structurally different from mammalian hypothalamic LHRH. These studies demonstrated that arginine in position 8 is substituted by a neutral amino acid. On the ...
Ziegler R - - 1984
An adipokinetic hormone was purified from corpora cardiaca of au adult Manduca sexta (tobacco hornworm)by reversed-phased high performance liquid chromatography. The following amino-acid composition was determined: 2 Thr, 2 Ser, Glx, Gly, Leu, Phe, Trp. The adipokinetic activity was tested in adult Manduca. In a bioassay in which activation of ...
Folkers K - - 1984
beta-Benzamido-alpha-(3-pyridyl)-DL-alpha-alanine hydrochloride was synthesized from 3-pyridinecarboxyaldehyde via the azlactone which was hydrolyzed to the acrylic acid before hydrogenation. The methyl ester was effectively resolved with subtilisin. The optical purity of the D-isomer was established, since the D-isomer was used in synthesis of antagonists of the luteinizing hormone releasing hormone.
Nestor J J JJ - - 1984
In a continuation of our studies on the effects of hydrophobic substitutions in analogues of luteinizing hormone-releasing hormone (LH-RH), we have synthesized LH-RH antagonists containing the very hydrophobic amino acid 3-(2-naphthyl)-D-alanine (D-Nal(2)). The D-Nal(2) substitution was found to be effective when incorporated in positions 3 and 6. The most potent ...
Lorenson M Y - - 1984
Cysteamine [2-mercaptoethylamine (CySH)] displays a variety of neuroendocrine effects, the most potent being the depletion of immunoassayable tissue PRL. The present study used bovine adenohypophysial secretory granules to characterize this inhibition of measurable hormone (assayability). CySH decreased assayability in a dose-dependent manner at pH 7.4, with 50% inhibition observed close ...
Ogawa K - - 1984
LH and progesterone added to cultures of the follicle wall of hens increased the total activity of neutral and acid proteases and collagenase and the increase was greater for follicle tissues from the stigma region. Adenohypohysectomy of hens resulted in the decreased activities of neutral and acid proteases and collagenase ...
Ho T L - - 1984
The effect of combination of the hydrophilic aza-Gly substitution (NHNHCO) at position 10 with hydrophobic, unnatural D-amino acids in position 6 on the potency of luteinizing hormone-releasing hormone (LH-RH) analogues has been investigated. Previously the aza-Gly residue was shown to provide protection from enzymatic cleavage and lead to potency increases ...
Schuh B A - - 1984
Two monophagous sawflies,Neodiprion dubiosus andN. rugifrons, actively avoid feeding on the current season's needles of jack pine,Pinus banksiana, while the polyphagousN. lecontei feeds indiscriminately on foliage of all age classes. Bioassay studies with needle extracts indicate thatN. dubiosus andN. rugifrons larval feeding preference is governed by a group of tricyclic ...
Szirtes T - - 1984
Twenty-four thyrotropin-releasing hormone (TRH) analogues containing mainly aliphatic amino acids in position 2 were synthesized and tested for central nervous system (CNS) and hormonal (TSH) activity. Application of the pentafluorophenyl ester method in the syntheses resulted in optimal yields and high purity of the products. The neutral tripeptides pGlu- Nva ...
Menéndez-Patterson A - - 1984
Significant amounts of immunoreactive glucagon (IRG) were determined in acid-ethanol and acid-saline extracts of human thyroid. Glucagon content of healthy thyroid, expressed as ng/g wet tissue or pg/mg protein, was significantly greater after an acid-alcohol extraction than after an acid-saline one. Furthermore IRG in acid-alcohol extracts of healthy tissue was ...
Hidiroglou M - - 1984
The relationship of zinc to morphologic, physiologic, and metabolic functions in the male reproductive system are summarized, and gaps in current understanding are pointed out. Semen and its constituents generally contain high zinc, although concentrations vary among animals and species; the relationships between zinc and fertility of semen is unclear. ...
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