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V Varró

Publications and source records attributed to V Varró.

At least 145 records · Page 8Linked to original sources
PubMed1978

Pentagastrin analogs containing alpha-aminooxy acids, I. Synthesis of analogs substituted at the N-terminus.

Nine new pentagastrin analogs containing a free or protected alpha-aminooxy acid at the N-terminus were synthesized stepwise. Analogs containing leucyl, norleucyl, norvalyl, L- and D-2-aminodecanoyl residues instead of methionyl residue were also prepared. The peptides were synthesized by the active ester method with subsequent removal of the protecting groups. The purification of the end products was performed by crystallization or column chromatography on silica gel.

Amino Acid Sequence↗
PubMed1978

Pentagastrin analogs containing alpha-aminooxy acids, II. Simultaneous substitutions at the N- and C-terminus.

Twenty-seven new pentagastrin analogs containing free or protected aminooxy acids at the N-terminus and D-2-aminooxy-3-phenyl-propionic acid, L-(4-chlorophenyl)glycine, L- and D-phenylglycine, or L- or D-cyclohexyglycine instead of the C-terminal L-phenylalanine and analogs extended by aminooxyacetic acid at the C-terminus, were synthesized stepwise. The end products were purified by chromatography on DEAE-cellulose or silica gel.

Amino Acid Sequence↗
PubMed1978

Pentagastrin analogs containing alpha-aminooxy acids, III. Biological studies and structure-activity relationships.

The stimulation of gastric acid flow by thirty-six new pentagastrin analogs administered intravenously, intrajejunally and intrarectally was determined in rats. Some of the analogs are several times more active than the pentagastrin (Peptavlon, I.C.I.) used as control. Unlike the control, some analogs are absorbed in active form from the jejunum. The N-terminal substitution with alpha-aminooxy acids seems to increase the gastric secretory response, probably by improving the enzymatic resistance of the molecule to various enzymes. None of the analogs tested significantly inhibit the gastric acid output in rats induced by pentagastrin. Structure-activity relationships are discussed.

Animals↗
PubMed1978

Interrelation between gastric blood flow and HCl secretion in dogs. The basal condition and influence of secretory stimulants and vasoactive substances.

Total and mucosal blood flow in the nonsecreting stomach and the interrelation between local blood flow changes and gastric hydrochloric acid secretion as influenced by various drugs or hormones were investigated in 188 anaesthetized dogs. Substances acting on gastric acid secretion (histamine, pentagastrin, atropine and metiamide) and those showing vasoactive properties (norepinephrine, epinephrine, Hypertensin, nicotinic acid and glucagon) were used. Instillation of 0.1 N HCl solution into the stomach provided a good estimate of the mucosal blood flow of the nonsecreting stomach as measured by the aminopyrine clearance technique of Jacobson et al. Simultaneous recording of the total gastric blood flow with an electromagnetic blood flowmeter revealed the distribution of blood flowing through the mucosal and non-mucosal (submucosa-muscle) tissues of the resting stomach. During acid stimulation a shift of the gastric blood flow to the mucosa was observed, which may reach even 75--80% of the total amount of the blood supply during a given period. Metiamide entirely inhibited the gastric acid secretion induced by both histamine and pentagastrin, but did not parallelly diminish mucosal blood flow. Given during histamine infusion, glucagon strongly inhibited acid secretion while it did not decrease mucosal blood flow.

Aminopyrine↗
PubMed1977

Effect of local circulatory arrest on the structure of the enterocytes of the isolated intestinal loop.

Fusion of the microvilli of the enterocytes, breakdown of the microvillous structure, vacuolization of the cytoplasm, and separation of the cells from one another, were observed in the early period of anoxia in the isolated small intestinal loop of dog. Filling the intestinal lumen with isotonic glucose solution inhibited the occurrence of the morphological changes observed. These observations furnish new data to the understanding of the very initial stage of small intestinal cell destruction due to anoxia.

Animals↗
PubMed1977

[Submicroscopic structure of the jejunal mucosa of human fetuses].

Authors investigated the submicroscopic structure of the jejunal mucosa of 6--12 week old human foetuses, obtained from arteficial abortions. It was established, that in this age the jejunal mucosa differentiates and develops intensively. In the third month it is build up of morphological units enterocytes. Their structure is morphologically similar to that of the enterocytes of the adult, although in this age they have no function at all.

Epithelial Cells↗
PubMed1977

[Changes in the structural localization of glycogen during glucose resorption].

Quantitative changes in the glycogen granula contents of the dog's small intestinal mucosa were investigated with light microscopy using Best-carmin dying. In fasting animals the glycogen could be detected in a patchy arrangement in the supranuclear cytoplasmic region of the enterocytes. During glucose abasorption glycogen appeared in continually increasing quantities also in the lamina propria. Injecting Glucagon (50-100 microgram/15') into the artery of the intestinal loop during glucose absorption, glycogen totally disappeared from the enterocytes, while it remained unchanged in the cells of the lamina propria.

Animals↗
PubMed1976

The distribution of 3H-gastrin and 14C-pentagastrin in the blood and lymph of rats.

3H-gastrin (0.83 mug/rat) or 14C-glycine-pentapeptide amide (100 mug/rat) were injected into the femoral vein in various groups of rats and radioactivity was measured in the arterial blood plasma and thoracic duct lymph in consecutive 5--10 min. periods for 60 minutes. Radioactivity excreted in the bile for 30 minutes was injected into the blood and lymph was followed for 120 minutes. It has been observed that labelled gastrin or pentagastrin activity reaches its peak in the plasma in the 5th minute after intravenous injection. Next, activity in the plasma decreased after the injection of labelled gastrin, but remained unchanged after the injection of labelled pentagastrin. In the lymph, radioactivity reached its peak value between 5--15 min. after the injection of the labelled hormones. This peak value was two- to threefold of plasma radioactivity measured at the same periods. After the intravenous injection of labelled pentagastrin radioactivity was excreted in the bile; injecting this radioactive bile into the jejunal lumen, radioactivity was reabsorbed mainly into the blood circulation.

Animals↗
PubMed1976

Diagnostic evaluation of gastric analysis (test meal) in Hungary.

On the basis of information received from 128 medical wards, the frequency of gastric analysis (test meal) used as a clinical diagnostic procedure, the spreading of the different methods and other problems connected with the examination are analysed. In about 3/4 of the institutions the test meal is performed in patients with all kinds of gastric complaint. This incidence decreases to 50% if the X-ray finding is positive. As acid-stimulants caffeine and a moderate dose of histamine are used most frequently. Of the data supplied by the test meal, the value for acid concentration (acidity) is registered by most of the examiners. The authors consider it as suprising that outdated methods such as a qualitative lactic acid assay (47%), isolation of Boas-Oppler's bacillus (25%) and of sarcinas (21%) are still in frequent use. The data are compared to the results of a similar survey made in England.

Gastric Acidity Determination↗
PubMed1976

Clinical significance and perspectives of gastrointestinal peptide hormones.

Present knowledge about gastrointestinal peptide hormones is discussed from three points of view: (a) diagnostic significance of these hormones; (b) states characterized by over-production or deficiency of peptide hormones; (c) clinical application and perspectives of gastrointestinal hormones. The data in the literature are subjected to a critical analysis; in addition, the author's own experiments are discussed.

Anemia, Pernicious↗