Kinetics of wheat flour water uptake.

The kinetics of wheat flour water uptake at 15, 25, 35 and 45 degrees C and different relative humidities from 43.2 to 85.9 was investigated. The water uptake curves obtained were well described by the first-order kinetics equation. A suitable general empirical model was found that includes the effect of temperature and relative humidity.

[The effect of the beta adrenomimetic trimethoquinol and its rigid tetrahydroberberine conformer on histamine liberation induced by compound 48/80 in mast cells]. / Einfluss des beta-Adrenomimetikums Trimethoquinol und seines rigiden Tetrahydroprotoberberin-Konformers auf die durch Substanz 48/80 induzierte Histaminfreisetzung aus Mastzellen.

The effects of the beta 2-adrenomimetic trimethoquinol (TMQ) and one of its rigid tetrahydroprotoberberin conformer - compound Is-35 - on the histamine content and the compound 48/80 induced histamine release have been studied. The histamine content in skin parts of ears and in the whole heart of male rats has been determined spectro-photofluorometrically. TMQ and Is-35 were injected in doses of 3 mumol/kg and compound 48/80 in increasing doses (1, 2 and 3 mg/kg) during 3 successive days. It has been found that the antagonizing effect of TMQ on the mast cell histamine release is tissue-dependent: it prevents the release of 20% of the compound 48/80-releasable histamine in ears and of 40% in heart. Is-35 has not effect on the compound 48/80 induced histamine release in ears and prevents the release of only 12% of the compound 48/80-releasable histamine in heart. The morphological studies show quantitative and qualitative changes in the heart mast cell population which are in good agreement with the biochemical data obtained. The fixation of the flexible part of the TMQ molecule in a tetrahydroprotoberberin configuration results in a reduction of the antagonistic activity towards the compound 48/80 induced histamine release. On the basis of this finding it could be suggested that an aporphin-like conformation of the TMQ molecule is responsible for its activity established.

Neuro-endocrine effects of isotheoline.

Experiments are carried out to study the effect of isotheoline (IST) on the secretion of prolactin (PRL), somatotrophic hormone (STH) and testosterone, using cats and Wistar albino rats of both sexes. PRL, STH and testosterone using cats and wistar albino rats of both sexes. PRL, STH and testosterone were determined radioimmunologically at the 10th, 60th and 120th min after the administration of IST in doses of 0.5 to 5 mg/kg. Comparative experiments were carried out with bromocryptine and glaucine--1 mg/kg i.p., as well as experiments involving the administration of IST on the background of the dopaminergic antagonists haloperidol and pymoside--1 mg/kg i.p. The results obtained show that in doses not exceeding 1 mg/ks IST increases the plasma level of testosterone and, similar to bromocryptine, reduces the plasma level of PRL and increases that of STH. These effects are less pronounced for the 5 mg/kg dose and they are antagonized by the dopaminergic antagonists used. It is assumed that IST, similar to bromocryptine, achieves the described effects through selective stimulation of the D2 dopaminergic receptors involved in neuro-endocrine mechanisms responsible for the control and release of the hormones studied.

Flavonoids with antioxidant action (naringin and rutin) and the release of mastocytic and nonmastocytic histamine.

In view of the data about the antioxidant mechanism of the membrane-stabilizing action of the bioflavonoids, the participation of this mechanism in the release of histamine as well is assumed to be possible. Experiments are carried out on 35 male albino rats. The effect of the flavonoids naringin and rutin on the level of mastocytic and nonmastocytic histamine is studied, as well as on its release induced by compound 48/80 (2 mg/kg i. p.). The substances are applied intraperitonealy in doses of 200 mg/kg; corresponding to 10% DL50. The histamine content is determined fluorimetrically by the method of Schore et al. (1959). The results show that naringin and rutin have no effect on the levels of mastocytic and nonmastocytic histamine. They prevent the release of mastocytic histamine, induced by compound 48/80.