摘要:

The transport (membrane, Na+-K+-stimulated or Na+-K+-dependent) ATPase (EC 3.6.1.3) was prepared from fundic gastric mucosa of operated patients and the histamine effect was studied on its activity. It has been observed that histamine significantly stimulated the Mg2+-dependent part, on the one hand, and inhibited the total and Na+-K+-dependent ATPase activity from membrane fractions of human gastric mucosa, on the other hand. The interrelationship between the transport ATPase system and the adenyl cyclase system, at the level of the cell membrane, is reviewed.

ISSN:0031-7012    

DOI:10.1159/000136539

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The blood levels of 14C, emanating from 14C-acetyl-salicylic acid (14C-ASA) p.o. and 14C-salicylic acid i.v., were decreased and unchanged, respectively, by the concomitant oral ingestion of phenacetin. Subsequent investigation showed that phenacetin: (a) did not affect the total renal excretion of 14C or ASA metabolites; (b) enhanced the retention of 14C, from either 14C-ASA or 14C-phenacetin, in the stomach contents and stomach tissues; (c) delayed stomach emptying, and (d) did not form undialyzable or insoluble complexes with ASA. It was concluded that phenacetin reduced the blood levels of salicylate by inhibiting stomach emptying.

ISSN:0031-7012    

DOI:10.1159/000136540

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The brief neuromuscular blocking action of [4,4’-biphenylene-bis-(2-oxoethylene) ]-bis-[(di-2-ethoxyethyl) methyl-ammonium bromide], DEO, was studied on rat sciatic nerve-gastrocnemius muscle in vivo and frog sciatic-gastrocnemius in vitro. The release of acetylcholine induced by electrical stimulation of the frog sciatic nerve was not affected by DEO at concentration of 1.3 × 10-5M which produced the neuromuscular blockade. This result indicates that DEO does not inhibit acetylcholine release nor synthesis to paralyze cholinergic neurons although it is an analog of hemicholinium. Low doses of DEO (0.1–0.3 mg/kg or 1/20–1/7 of ED50 to block the neuromuscular junction) did not affect ED50 of d-tubocurarine but enhanced the neuromuscular blocking actions of decamethonium drastically (3- to 10-fold) on rat sciatic-gastrocnemius preparation. These results suggest that the major site of action of DEO is at the junctional cholinergic receptor but not at the postjunctional ‘curare’ receptor. The LD50 of DEO determined with ICR mice was

ISSN:0031-7012    

DOI:10.1159/000136541

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Studies were performed on the effects of the activation of the kinin-forming system on the action of chlorpromazine in rats and mice. It was found that in animals with CNS kinin enzymes previously activated with kallikrein, or in animals which had been given bradykinin, the psychodepressive activity of chlorpromazine became markedly higher. The administration of Trasylol® brought about a decrease of the postkallikrein activation of kinin-generating enzymes and abolished the potentiating kallikrein effect on the action of chlorpromazine. Under multiple pathological conditions which are followed by increased kinin levels, an altered potency of drugs acting on CNS should be taken into consideration

ISSN:0031-7012    

DOI:10.1159/000136542

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Carbenoxolone sodium at 10 mg/kg when given subcutaneously to adrenalectomized rats, does not show a retention of urinary sodium ion comparable to that observed with 0.2 μg/rat (1.0 μg/kg) of aldosterone, nor does carbenoxolone sodium at 10 mg/kg show any significant increase of urinary potassium excretion, whereas, under the same conditions, a significant increase in potassium excretion was observed with aldosterone at 0.2 μg/rat. At a higher dose of carbenoxolone sodium 50 mg/kg, which is comparable to 10 times the clinical dose in man, sodium retention and increased potassium excretion was observed which was significantly different from control animals but less than that observed for 2.0 μg of aldosterone. In similar experiments, no potentiation of aldosterone effects was observed when carbenoxolone sodium at 10 mg/kg was given concomitantly with aldosterone at 0.2 μg/rat (1.0 μg/kg). The present experiments confirm the anti-natriuretic action of carbenoxolone sodium but failed to demonstrate any enhancement of the mineralocorticoid action of aldosterone by carbenoxolone s

ISSN:0031-7012    

DOI:10.1159/000136543

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Water-soluble, non-nitrogenous polysaccharides isolated from dermatophytes were tested for prophlogistic activity in the rat. Unlike the type II galactomannans, glucan, mannan and type I galactomannans from various dermatophyte species induce a dose-related swelling of the paw, which follows the same time-course as the oedema caused by dextran. The effect of the dermatophyte polysaccharides can also be antagonized by aminopyrine, tripelennamine, BOL and methysergide. The demonstrable prophlogistic activity of the dermatophyte polysaccharides studies is therefore presumably due to liberation of serotonin and histamine.

ISSN:0031-7012    

DOI:10.1159/000136544

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Rats injected for 5–10 days with diphenyl-hydantoin (DPH) 75 mg/kg exhibit increased liver content of lactate dehydrogenase. However, the liver weight, the hepatic content of cytochrome P-450 and the microsomal ethanol oxidizing activity (MEOS) were unchanged. When rats were injected for 33–37 days with DPH (75 mg/ kg), the liver weight, the hepatic content of lactate dehydrogenase and cytochrome P-450 content, as well as hepatic MEOS activity, increased significantly. MEOS activity in the liver correlated significantly with lactate dehydrogenase activity (r = + 0.70) and cytochrome P-450 content (r = + 0.

ISSN:0031-7012    

DOI:10.1159/000136545

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The kinetics of hepatic microsomal ethanol oxidation (MEOS) was studied in microsomal suspension from rat liver. The estimated maximum elimination rate was 117 nmol acetaldehyde/ min/g liver and the half-saturation concentration 12.7 mmol ethanol/l. The MEOS activity was not influenced by the presence of antipyrine 0.1 mmol/l and 1.0 mmol/l in the microsomal incubations.

ISSN:0031-7012    

DOI:10.1159/000136546

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The relationship between the metabolic disposition of acetaminophen and the susceptibility of hamsters, mice and rats to acetaminophen-induced liver necrosis has been examined. The fraction of low doses of acetaminophen converted to the mercapturic acid metabolite was highest in the most susceptible species (hamsters, mice), and lowest in the more resistant species (rat). Pretreatment regimens known to potentiate the hepatotoxicity increased mercapturic acid formation whereas treatments which protect from liver damage decreased mercapturic acid formation. The data suggest that the activity of the mercapturic acid-forming pathway in vivo reflects the activity of the hepatotoxic pathway. As the dose of acetaminophen was increased to hepatotoxic levels, the fraction of the dose excreted as the mercapturic acid decreased markedly, commensurate with the known depletion of hepatic glutathione under these conditions. It is suggested that the normal metabolic intermediate which conjugates with glutathione in the mercapturic acid pathway is also the electrophilic metabolite which in the absence of glutathione arylates hepatic macromolecules and causes cell death.

ISSN:0031-7012    

DOI:10.1159/000136547

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Dopamine-β-hydroxylase (DBH) catalyzes the conversion of dopamine to norepinephrine and is present in human plasma. Plasma DBH activity shows little intrasubject variation with time, but varies greatly between subjects. Plasma DBH activity varied over a 40-fold range in a population of 140 normal adult volunteers with the distribution of activities skewed toward the lower values. Square root transformation of the plasma DBH activity values corrected the skewness to approach normal distribution. No correlation was found between plasma DBH activity and blood pressure, heart rate, or body weight. An antibody directed against bovine adrenal DBH has been prepared in rabbits which specifically inhibits human plasma DBH. In a population of 50 healthy blood donors we found a high, positive correlation (r = + 0.90) between plasma DBH activity and the quantity of DBH antibody required to completely remove enzyme activity from plasma. This correlation suggested that the large range in plasma DBH activity in the adult population reflects a similarly large range of immunoreactive DBH protein, and is not due to variations in plasma levels of enzyme inhibitors or activators

ISSN:0031-7012    

DOI:10.1159/000136548

出版商:S. Karger AG    

年代:1974

数据来源: Karger