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F Diel

Publications and source records attributed to F Diel.

27 records · Page 2Linked to original sources
PubMed1984

Somatostatin-induced histamine release in mast cell incubates from thymusaplastic nude rats.

Both cyclic and linear somatostatin-14 are potent histamine secretagogues in rat mast cell incubates. Linear somatostatin-14 is more effective than cyclic somatostatin-14 in a concentration range up to 10(-6) mol/l, in normal Sprague-Dawley rats, and even more responsive in sensitized hooded Lister rats. This additional mast cell stimulation capacity of linear somatostatin-14 depends on circulating IgE levels. No differences are observed in athymic rat mast cell incubates between the linear and the cyclic isomer of somatostatin-14. A direct unspecific interaction of linear somatostatin with cell surface antibodies can be concluded.

Animals↗
PubMed1983

Histamine secretion in leukocyte incubates of patients with allergic hyperreactivity induced by somatostatin-14 and somatostatin-28.

Somatostatin is a potent histamine secretagogue found not only in rat mast cells but also in human leukocyte preparations. In concentrations greater than or equal to 5 mumol/l, somatostatin-14 induces histamine release, which correlates with the basophilic blood cell count, as shown in samples from allergic patients suffering from slight basophilia. Somatostatin-14 is twice as effective as somatostatin-28 on a molar basis, and acylating the tetradecapeptide with N-hydroxysuccinimidyl-p-hydroxy-phenyl-propionate decreases significantly the potency of histamine release.

Adult↗
PubMed1982

Somatostatin--a regulatory peptide of clinical importance.

Somatostatin was first discovered in the hypothalmus and has since been located in many parts of the central and peripheral nervous system, as well as in the pancreas and the gastrointestinal tract. Its main biological activity is to inhibit the action of somatotropin (growth hormone, STH, GH) and a number of other hormones. The therapeutic value of somatostatin has been demonstrated in the treatment of both acute bleeding gastric ulcers and acute pancreatitis. In addition, the measurement of somatostatin in the blood is a useful method for the screening of somatostatin-producing tumours. This paper reviewed the location, action, clinical significance and measurement of somatostatin.

Adrenal Glands↗
PubMed1981

Application of rat mast cell incubates as a possible short-time test for sensitizing occupational chemicals.

The direct action of sensitizing occupational chemicals (formaldehyde, phenol, phenylhydrazine, p-aminophenol) on rat mast cells was investigated by determination of histamine using HPLC separation and fluorimetric detection. It turned out that dispensed mast cells from immunized and non-immunized Wistar-rats are more sensitive than small-cut lung tissue slices. Passive cutaneous anaphylaxis was negative after a fortnight sensitizing experiment with the here described occupational chemicals. Short-time tests with rat mast cells reflect anaphylactoid response and are suitable for the screening of sensitizing chemicals.

Anaphylaxis↗
PubMed1981

Failure of somatostatin and beta-endorphin to affect bovine adrenal cortex cells in vitro.

The main intention of this study was to examine the effect of cyclic somatostatin (SRIF) on bovine adrenal cell activity in vitro. beta-Endorphin was applied in another course of experiments. Basal aldosterone secretion when measured was found to be 0.86 +/- 0.33 ng per 10(5) cells and 1.5 h incubation time in the glomerulosa cell fractions. Cortisol production was 1.6 +/- 0.3 ng per 10(5) cells in the fasciculata/reticularis cell incubates respectively. No effect was observed when cyclic somatostatin (SRIF) was added to cell incubates of the bovine adrenal cortex. However, aldosterone secretion was increased 4.5-fold in the presence of 10(-9)M ACTH or 10(-8)M At II. Cortisol production was enhanced similarly after addition of 10(-9)M ACTH.

Adrenal Cortex↗
PubMed1981

Somatostatin binding factor from chicken pancreas.

A soluble somatostatin binding factor was detected in cell-free extracts from chicken pancreas. For binding measurements Tyr1-somatostatin was radio-labeled with 125I by the lactoperoxidase technique. Specific radioactivity of about 18.5 MBq/nmol was achieved. Maximal total binding is approximately 0.17 (B/T) in the presence of 30 mg/l pancreatic protein. The specific binding is 0.10 and is suppressed by addition of 1 mg/l synthetic cold cyclic somatostatin. The dose-response curve of synthetic cyclic somatostatin is in the range of 0.6-600 nmol/l. Ca2+ and reduced thiol-reagents inhibit the specific binding. Insulin, glucagon and corticotropin show a low, and luliberin and reduced somatostatin a high cross-reactivity. Molecular weight was estimated by gel filtration and the specific binding molecule was eluted at a Kav = 0.2 on an Ultrogel (AcA 54) column. This corresponds to Mr 40 000. Electrophoretic properties of the binding complex and semipurification by polyacrylamide disc gel electrophoresis: relative mobility of the 125I-Tyr-somatostatin binding complex is about 0.6. Relative mobilities of binding-protein fractions are 0.71 and 0.74. Highest relative specific binding was detected in the (100 000 g) cytosol fractions. Binding with cell-free extracts from the splenic lobe area was 4-fold higher than that from other parts of the chicken pancreas.

Animals↗