ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01805.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:Addition of 1,1,1‐trichloroethane (TCE),in vitroto synaptosomes isolated from the mouse cerebellum and cerebral cortex inhibited the slow phase of K+‐stimulated45Ca2+influx and the net45Ca2+influx (Δk). In the brain stem, however, TCE increased the fast and slow phases of calcium uptake under depolarizing conditions and also Δk. The non‐depolarized calcium influx was not altered by TCE addedin vitro.Two hours after injection of TCE (2.4 g/kg) the calcium accumulation in the presence of high K+was lowered in the cerebellar synaptosomes, while it was increased in brain stem synaptosomes. TCE administeredin vivodid not alter the calcium influx into cerebrocortical synaptosomes nor did it affect the non‐depolarization‐induced45Ca2+influx. Thus, these data indicate that TCE may influence voltage‐dependent calcium channels in mouse brain

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01806.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:Male mice were exposed to two different preparations of PCBs. The pure congener 2,2′,4,4′,5,5′‐hexachlorobi‐phenyl (6‐CB) was given at daily doses of 4, 20, and 40 mg/kg b.wt. during the perinatal or pubertal period. A technical mixture of PCB (Clophen A50®) was administered during puberty at daily doses of 8, 40, 80, 120, and 160 mg/kg b.wt. Treatments were, in the different experiments, carried out every second or third day for three to five weeks. Treatment during puberty was started when the mice were 5 weeks old. The perinatal exposure was started on day 13 of gestation and ended on day 24 post partum. There were no significant differences in the plasma levels of testosterone between the treated mice and the controls after any of the treatments, but there was an increase in the relative testes weights for the animals treated perinatally. No influence on the biosynthesis of testosterone in the testicular interstitial cellsin vitrocould be

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01807.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:In untreated rats, the intraperitoneal injection of putrescine evoked a typical wet‐dog shake response, that was maximal at a dose of 300 mg/kg and at room temperature (22°) (number of shakes: 84.00$pL17.90/hr). In a hot environment (30°) the number of shakes was markedly reduced (29.60$pL5.19/hr). The putrescine‐induced shaking behaviour was unaffected by atropine, bicuculline, chlorpheniramine, cimetidine, methysergide, naloxone and noradrenaline, but was markedly antagonized by morphine. Naloxone pretreatment nullified the antagonistic activity of morphine. Histological studies showed marked alterations in brain vascular permeability, which was increased by putrescine. Morphine completely prevented this putrescine‐induced vascular effect. These results suggest a correlation between WDS produced by putrescine and increase in brain vascular permeability. Furthermore they show that morphine can affect brain vascular perme

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01808.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:Material injected into the cerebral ventricles can leave the cerebrospinal fluid (CSF) but remain in the cranial cavity. To analyze the disappearance of3H‐ and of14C‐labelled material from the cranial cavity, such material was injected into the lateral ventricles together with a bulk flow marker, labelled with the other radionuclide. In the present pilot study3H‐PAH and14C‐inulin were used. Five μl of a mixture was injected into each lateral cerebral ventricles in rats, which were killed at various intervals. The whole skull was analyzed without opening the CSF space after homogenization in the deep‐frozen state. The samples were combusted and analyzed by liquid scintillation counting. Probenecid, injected intraperitoneally, inhibited the removal of3H‐PAH from the skull cavity, as anticipated. Immediately after the intraventricular injection, however,3H‐PAH was transiently retained, probably by uptake into actively transporting tissue. After injection of probenecid, this delay in removal was reduced. The difference in disappearance rate between3H‐PAH and4C‐inulin was estimated by comparing the3H/14C ratio in the skulls with that in the injected solution, which appeared to be a better method than comparing the recover

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01809.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:Effects of alaproclate, an inhibitor of serotonin uptake, on the membrane of GH3/B6clonal pituitary cells were studied using whole cell patch clamp recording techniques. Application of alaproclate (5 μM) depolarized the cell and increased the rheobase. Such treatment also increased the frequency of spontaneous firing. It is suggested that alaproclate decreases the potassium conductance in a manner similar to 4‐aminopyridine and affects membrane calcium channe

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01810.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:A substantial proportion of a parenteral dose of emepronium given to dogs is excreted via the gastrointestinal tract by biliary excretion and by excretion through the intestinal mucosa (Hallénet al.1979). In the present paper the different routes of elimination were further investigated in mouse and man and compared to the dog. The disposition of emepronium‐derived radioactivity (14C) in the three species showed that about 45% was excreted via urine and 55% via faeces. The proportion of the faecal excretion of14C that could be referred to the intestinal route differed between the species and was about 20% in man, 60% in the mouse and most pronounced, 80%, in the d

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01811.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:To determine whether supplementation with the physiological radical scavenger, vitamin E, would modulate arachidonate metabolism in human inflammation, we performed equilibrium dialysis of rectum in eight patients with active ulcerative colitis confined to the rectum. The patients, all off drug treatment, were supplemented with 1920 IU/day of α‐tocopherol and had rectal dialysis done at entry and after three and 14 days. Luminal concentrations of prostaglandin E2(PGE2) and leukotriene B4(LTB4), determined by radioimmunoassay in purified dialysates, were significantly raised compared to healthy controls. Supplements caused no change in these levels either at day 4 or 15, although serum‐tocopherol showed a 3‐fold increase. Also disease activity was unaffected. This failure of vitamin E supplementation to suppress the mucosal release of PGE2and LTB4in active inflammation does not encourage controlled trials on the effect of oral vitamin E in ulcerative c

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01812.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:The therapy of copper poisoning and of Wilson's disease with 2,3‐dimercaptopropane‐1‐sulphonate (DMPS) may increase the copper‐induced haemolysis. Some aspects of the mechanism of this effect were investigated. The possible generation of activated oxygen species during the interaction of Cu++and DMPS was studied using a chemiluminescent method detecting oxygen radicals. It was found that incubation of DMPS with copper ions (free or bond with erythrocyte membranes) is accompanied with generation of oxygen radicals. Activated oxygen species produced via O2‐are able to increase the haemolytic effects of cupric salts. Hence DMPS treatment in cases of copper poisonings or Wilson's disease may involve risk of side effects on the basis of activated oxygen species g

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01813.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY

摘要:

Abstract:Hearts from rats, which received high doses of furosemide alone or the same doses of furosemide plus amiloride in a diet with low magnesium content for 4 weeks, were isolated and perfused in the Langendorff mode. After 15 min. of normoxic control perfusion no differences were found between the two groups of hearts with respect to cardiac physiology. After 20 min. of subtotal, global ischaemia and 15 min. of reperfusion the furosemide plus amiloride hearts showed a significantly higher recovery of function (judged by pressure rate product and coronary flow rate) than furosemide hearts. However, the myocardial content of adenosine triphosphate, creatine phosphate, and electrolytes at the end of the experiment exhibited no difference between the two groups. In separate experiments it was found that the addition of amiloride to the furosemide regimen significantly raised and almost normalized the values of plasma magnesium and potassium. Myocardial calcium was lower, whereas the magnesium and potassium content in the hearts was not different from the furosemide group. It is concluded that the administration of amiloride to rats provided high doses of furosemide and marginal magnesium supplies afforded some protection upon the ischaemic heart.

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1987.tb01814.x

出版商:Blackwell Publishing Ltd    

年代:1987

数据来源: WILEY