Pharmacological research communications最新文献

Disopyramide (D) kinetics were studied after single oral dose (200 mg) in ten elderly male patients (mean age: 75.5 yrs) without clinical or laboratory signs of hepatic, renal or cardiac disease, and in six healthy male subjects. They were all non smokers and had not taken alcohol for at least 10 days. Peak plasma concentration and area under the curve (AUCo-oo) were 54% and 51% respectively higher in the elderly group, whereas plasma half life was virtually the same in both groups (about 9 hrs).

The major D metabolite, mono-N-desisopropyldisopyramide (MND), showed a tendency towards an increase of AUCo-24h and T1/2 but did not reach the 5% significance level. Eight of the ten elderly patients but only tow of the six young subjects complained of anticholinergic side effects. On the basis of the pharmacokinetic changes observed (and provided that plasma protein binding is unchanged), D oral dose should be reduced by 1/3, without modifying the dosage interval.

Flavonoid production and accumulation during the ontogenic cycle of Passiflora incarnate L. was studied. The highest concentration of isovitexin accurred between pre-flowering and flowering stages. The greatest accumulation of flavonoids took place in the leaveas. Furthermore some pharmacodiagnostic characteristics of the drug of P. incarnata were specified using a Scanning Electron Microscope.

Qualitative and quantitative variations in the diterpene alkaloids content in the neomontanum subspecies of Aconitum napellus, growing near lake of Como, were studied throughout its complete onthogenetic cycle. Aconitine, N-deethylaconitine and two compounds with m.w.- 688 and m.w. = 629 have been detected in the various organs of plant almost at any time during the vegetative cycle.

The active principles of the male fern, Dryopteris filix-mas (L.) Schott., consisting of a mixture of phloroglucinol derivatives called “crude filicin”, are localized by means of fluorescence microscopy under U.V. 365 nm and monochromatic blue 435-490 nm lights.

Crude filicin is autofluorescent, and therefore may be easily localized in the internal glandular hairs of the intercellular spaces of rhizome and leaf bases parenchyma, without pre-treatment of sections.

Localization is confirmed both morphologically and chemically, and is possible on a fresh material, as well as on a desiccated one.

The test allows also a complete anatomical examination of sections, and may be useful, for its easiness and quickness, in further taxonomic or pharmacognostic studies.

Atropa belladonna L. (Solanaceae) tincture was compared with atropine for its anticholinergic activity, both in vivo and in vitro. In all tests, the biological activity of A. belladonna resulted greater than that suggested by its alkaloid content. The results suggest the presence in A. belladonna leaves of unknown compounds with a significant biological activity.

BN-52021 preserves “in vitro” the actively sensitized guinea-pig heart from the immunological reaction. This ginkgolide reduces mediator release (histamine, thromboxane-A₂ and slow reacting substance of anaphylaxis) in a dose-dependent manner, particularly that of histamine. These results evidence either an important role for PAF in guinea pig anaphylaxis or a wider spectrum of activity for BN-52021.

The relaxant effect of resveratrol on guinea pig isolated trachea (EC50=100 μM) was not due to interactions with histaminergic or cholinergic systems, but appeared to be influenced by beta-blockers, indomethacin and mepacrine. Antigen-induced contraction on sensitized trachea was partially antagonized by resveratrol. Resveratrol action may be partially related to arachidonic acid metabolism.