摘要:

A study on galanthamine hydrobromide (Nivalin®) pharmacokinetics was carried out on male Wistar rats following single intravenous and oral administration. Plasma samples were collected after decapitation of the animals. The drug concentrations were determined spectrophotofiuorometrically. A two-compartment open model was found to describe best the experimental data. Galanthamine has an elimination half-life of 40–50 min, a volume of distribution over 2 liters/kg, a plasma clearance of about 2 liters/h · kg and an oral bioavailability of about

ISSN:0031-7012    

DOI:10.1159/000138184

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

Plasma, heart, and extracardiac tissue verapamil concentrations were measured after sustained intravenous infusions in 11 dogs to determine the differential tissue accumulation of verapamil. A steady state verapamil concentration of 327 ± 50 ng/ml decreased the mean arterial blood pressure from 104 ± 9 to 90 ± 6 mm Hg (p = 0.08) and the P-R interval increased from 118 ± 4 to 176 ± 13 ms (p fat = skeletal muscle. Levels in the ventricular free wall were consistently greater than atrial levels, but no difference was observed between left versus right-sided cardiac chambers. In summary, affinity of different organs for verapamil is highly variable and organ-specific; furthermore, differential intracardiac chamber accumulation

ISSN:0031-7012    

DOI:10.1159/000138185

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

The effects of aging on acetaminophen metabolism and elimination in male Fischer 344 rats were examined after intravenous injection of 300 mg/kg. Age as a variable had only a small effect on the total clearance of acetaminophen. However, the fraction of administered dose recovered from urine as acetaminophen sulfate and the partial clearance to acetaminophen sulfate decreased while the fraction recovered as acetaminophen glucuronide and the partial clearance to acetaminophen glucuronide increased with increasing age. Renal clearances of acetaminophen and acetaminophen glucuronide were unchanged while that of acetaminophen sulfate decreased. These data point to an age-related decrease in sulfation and increase in glucuronidation of acetaminophen and further emphasize that the major conjugated metabolites are excreted by renal transport processes that operate under separate control. Moreover, they raise the possibility that advancing age may be accompanied by a general decline in processes that govern sulfate conjugate formation and elimination.

ISSN:0031-7012    

DOI:10.1159/000138186

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

The effects of two dopamine agonists, dopamine itself and SKF 38393, alone and in the presence of several dopamine antagonists, have been studied in the partially contracted, isolated and perfused renal artery of the rat. In this preparation, earlier used by other authors in vascular pharmacological experiments, the dopaminergic agents produced clear vasodilator effects which were inhibited by all antagonists used. Due to its low cost and simplicity, such a preparation would be of practical value in testing dopaminergic drugs.

ISSN:0031-7012    

DOI:10.1159/000138187

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

The effects of verapamil on gastric wall mucus and ulceration were studied in rats which were restrained and exposed to 4 °C (stress). Stress for 2 h significantly depleted stomach wall mucus and produced marked gastric glandular ulcers. Verapamil pretreatment (2, 4, 8 or 16 mg/kg), injected intraperitoneally 30 min before experimentation, significantly prevented stress-induced mucus depletion and gastric ulceration; however, it did not itself influence stomach wall mucus levels in nonstressed animals. Intragastric administration of carbenoxolone (100 or 200 mg/kg), also given 30 min before stress, exhibited similar actions as verapamil. A 15% solution of N-acetylcysteine (10 ml/kg), given orally, strongly decreased the mucus content in both nonstress and stress conditions; it induced ulcers in nonstressed rats, and worsened stress ulceration. These effects were not reversed by verapamil pretreatment. The influence of multiple-dose pretreatment with verapamil or carbenoxolone on mucus content and ulceration in the gastric glandular mucosa during stress is also discussed. It is concluded that gastric wall mucus depletion is likely to play an important role in stress ulcer formation; the antiulcer action of verapamil could partly be due to the preservation of mucus

ISSN:0031-7012    

DOI:10.1159/000138188

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

The effect of morphine, fentanyl, pethidine and pentazocine was studied in gerbils against air blast-induced seizures. Major, generalized seizures were suppressed by morphine (ED50 = 4.0 mg/kg s.c), fentanyl (ED50 = 64 μg/kg s.c), and pethidine (ED50 = 2.4 mg/kg s.c), but not by pentazocine. The anticonvulsant effect of the drugs was lost with higher doses which partly induced spontaneous convulsions. The comparatively high potency of pethidine in this model may point to a role of other receptors (or processes) besides the μ-receptor for this dru

ISSN:0031-7012    

DOI:10.1159/000138189

出版商:S. Karger AG    

年代:1986

数据来源: Karger

摘要:

Substance P and two recently identified neurokinins, substance K and neuromedin K as well as the nonmammalian tachykinin kassinin were compared for (a) histamine-releasing abilities from rat mast cells, (b) plasma extravasation effects on rat skin, and (c) wheal and flare responses on human skin. Among the four tachykinins, a significantly dose-dependent histamine release from rat mast cells and a flare response in human skin was observed only with substance P, indicating the possible implication of histamine in this response. On the other hand, the four peptides were similarly active on the wheal response (plasma extravasation produced by increased permeability of capillaries and venules) in human skin and on the plasma extravasation in the rat skin, suggesting a dissociation of effects and possibly of receptors.

ISSN:0031-7012    

DOI:10.1159/000138190

出版商:S. Karger AG    

年代:1986

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000138191

出版商:S. Karger AG    

年代:1986

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000138192

出版商:S. Karger AG    

年代:1986

数据来源: Karger

ISSN:0031-7012    

DOI:10.1159/000138183

出版商:S. Karger AG    

年代:1986

数据来源: Karger