ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00655.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:A possible toxic effect of components in nasal drops on chemotaxis by human granulocytes was studied. The vasoactive substances oxymetazoline chloride and xylometazoline chloride gave a successive reduction of chemotaxis down to zero for a concentration of 500 mg/l which is around that used in commercial preparations. The preservative benzalkonium chloride which is used in nasal drops in a concentration of 200 mg/l was deleterious for chemotaxis at a concentration of 0.8 mg/l. Thiomersal was deleterious for chemotaxis at a concentration of 1 mg/l which should be compared with a concentration of 24 mg/l used as preservative in nasal drops. Together with previous studies the present results indicate that the addition of preservatives in nasal drops should be questioned especially as they can be safely distributed without any risk of bacterial contaminations nowadays.

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00656.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:In dogs anaesthetized with pentobarbital, the left anterior descending coronary artery (LAD) was occluded for 90 min. so that about 1/2 of the original flow was allowed to flow (partial occlusion). Bevantolol (a β1‐adrenoceptor antagonist) or propranolol (a reference drug) was injected intravenously 30 min. after partial occlusion. Regional myocardial pH was measured by a micro glass pH electrode inserted in the LAD area. Partial occlusion decreased myocardial pH by 0.62 to 0.74. Bevantolol (1.0 mg/kg) or propranolol (1.0 mg/kg) significantly increased myocardial pH, that had been decreased by partial occlusion, within 60 min. after the injection. Restoration of myocardial [H+] (defined as return towards a lower [H+] to the preocclusion level) (calculated from the pH data) induced by bevantolol and that induced by propranolol were 64.0 and 66.4% (measured 60 min. after the injection), respectively. Bevantolol or propranolol decreased heart rate also. Even in the paced heart, bevantolol restored the myocardial [H+] that had been increased by partial occlusion. These results suggest that bevantolol has a favorable effect on the ischaemic myocardium as has propranolol, and that the pH effect of bevantolol is not primarily due to a decrease in heart ra

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00657.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:In vitrodialysis using human blood andin vivoextracorporeal haemodialysis trials with dogs, in the presence and absence of various chelating agents, showed that haemodialysis alone facilitated efficient removal of the metal, even in the absence of any of the chelating agents.In vitrohaemodialysis for 5 hr without chelating agents caused the removal of 85% of the arsenic (As) added to the blood 1 hr before the beginning of the treatment. Ten–33% of the single dose given to the dogs, were removed into the dialysate during the first treatment and 8–15% during the second. The amounts of As excreted in the urine of dogs given 0.25 mg As/kg b.wt./day for 6 days were 6.8–7.4 mg As/24 hr, while the same amounts of the metal were removed into the dialysate during haemodialysis for 5 hr. This demonstrates the advantage of employing haemodialysis over the conventional treatment for the enhanced removal of As from the

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00658.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:The effect of nicotine on the neuroleptic‐induced changes in striatal dopamine (DA) metabolism of mice was studied. To investigate the mechanism of action of nicotine, its interactions with apomorphine (APO) and γ‐hydroxybutyric acid (GHBA) were also investigated. Mice were given nicotine, (0.3–3 mg/kg subcutaneously) repeatedly (4 times) at 30 min. intervals. Haloperidol (HAL), (±)‐sulpiride (SUL), APO or GHBA were administered after the second nicotine dose. Hexamethonium was given to prevent the effects of nicotine on autonomic ganglia. The striatal contents of DA and of its metabolites homovanillic acid (HVA), 3,4‐dihydroxyphenylacetic acid (DOPAC) and 3‐methoxytyramine (3‐MT) were measured. The drug‐induced hypothermia in mice was controlled by increasing ambient temperature. At ambient temperature of 32–34° nicotine and HAL increased the striatal DOPAC and HVA contents additively, whereas APO counteracted the effects of nicotine at this ambient temperature. At 20–22° nicotine decreased the 3‐MT content which indicates reduced release of DA. In hypothermic mice nicotine inhibited better the HAL‐ and SUL‐induced increases of HVA content than those of DOPAC content suggesting that the neuroleptic‐induced increases in DOPAC and HVA contents are mediated partly by different mechanisms. In APO‐treated mice both the GHBA‐ and nicotine‐induced decreases of 3‐MT content fell further. GHBA did not alter the nicotine‐induced decrease of 3‐MT content and so this effect of nicotine may be mediated indirectly via GABAergic neurones. Unlike GHBA and APO nicotine decreased 3‐MT content only in hypothermic mice. Thus the mechanism of action of nicotine differs from that of GHBA and APO and could be a depolarization block perh

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00659.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:The antinociceptive effect of intrathecally administered carbachol at the L1/L2 level in the rat was evaluated using the tail immersion test. A dose dependent increase in the nociceptive reaction times was evident following intrathecal carbachol in the dose range of 2.5–15 μg. At doses of 20 μg and above, although still effective in the test, motor impairment was pronounced. The antinociception was antagonized with atropine, and with either pirenzepine (PZ) or AFDX 116, which are selective M1 and M2 muscarinic receptor blocking drugs, respectively. Spinal cholinergic pain modulation was also studied in rats pretreated with DSP4 (N‐2‐chloroethyl‐N‐ethyl‐2‐bromobenzylamine), which causes a selective depletion of the noradrenergic nerve fibres in the CNS. The increased latency times after spinal carbachol were attenuated in animals depleted of spinal noradrenaline by DSP4. In conclusion, spinal analgesia by carbachol in the rat may therefore be mediated through both M1 and M2 muscarinic receptor stimulation in the spinal cord. It is also concluded that this spinal cholinergic pain modulation is interacting with spinal noradrenergic nerve terminals, but that the mechanism of the interaction remains to

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00660.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:Disulfiram, which is metabolized to diethyldithiocarbamate, is known to greatly influence the tissue distribution of lead (Pb) and potentiate the toxic effect of lead in the central nervous system. Effects on δ‐aminolevulinic acid dehydratase (ALAD) activity and urinary δ‐aminolevulinic acid (ALA) excretion were studied in rats pre‐ and postnatally exposed to lead and disulfiram, singly or in combination. Pregnant rats were treated with lead (0.25% Pb in the drinking water), with disulfiram (0.1 mmol/kg orally twice a week) or with both lead and disulfiram from day 1 of pregnancy until weaning. After parturition the disulfiram was given subcutaneously directly to the offspring. ALAD activity in blood was inhibited to a similar extent in the group treated with lead alone and in the group treated with lead and disulfiram (7 and 10% of control activity, respectively). Liver and kidney ALAD activities were not affected by the combined treatment with lead and disulfiram. However, urinary excretion of ALA was increased twice as much in the group treated with lead and disulfiram as in the group treated with only lead. The haematocrits were also significantly more depressed after combined exposure to lead and disulfiram. Two weeks after cessation of exposure ALAD activity in blood was inhibited to 47% of control activity in both the lead‐ and the lead plus disulfiram‐treated groups. At this time there was no effect due to treatment on urinary ALA excretion or haematocrit. The results indicate that disulfiram probably influences the effects of lead on ALAD activity at the site of haem synthesis in the bone marrow. It is suggested that a lipophilic lead‐diethyldithiocarbamate complex is formedin vivo, resulting in a higher uptake of lead in the bone marrow with subsequent effects on haem

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00661.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:Single intravenous dose pharmacokinetics of theophylline in 10 rabbits were investigated before and after 5 days oral administration of verapamil in daily doses of 6 mg/kg. Verapamil caused a significant inhibition of theophylline elimination. Theophylline clearance was reduced from 126 to 98 ml/hr/kg (22.2%) whereas the steady state volume of distribution of the drug increased from 461 to 550 ml/kg (19.3%). The terminal half‐life of theophylline increased from 2.7 to 4.0 hr (49.8%

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00662.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:The sympathoinhibitory effects of ketanserin were investigated in the spontaneously hypertensive rat. In conscious rats ketanserin (0.1–10.0 mg/kg intravenously caused dose‐related reductions in blood pressure and heart rate (carotid artery). The heart rate reduction was prevented by chemical sympathectomy (reserpine) and in anaesthetized rats the heart rate reduction was correlated to a reduction in the directly recorded preganglionic sympathetic activity in the left renal nerve. Ketanserin had no presynaptic effects on the sympathetic nerve terminals as evidenced by the lack of effect on the tachycardia induced by electrical stimulation of the sympathetic outflow in pithed rats. In rats, catecholamine‐depleted by reserpine, the heart rate reduction was prevented, and in atropine‐pretreated animals there was a partial blockade of the bradycardic effect. We conclude that the lack of reflexogenic tachycardia in response to the hypotension induced by ketanserin treatment is partly due to a preganglionic inhibition of sympathetic nerve a

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00663.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY

摘要:

Abstract:The effect of eight months of alcohol intake on the number and affinity of muscarinic receptor sites in the rat pancreatic tissue were measured by using N‐3H‐methylscopolamine (NMS) as a radioligand. There were no differences in the receptor affinities for NMS between the alcohol‐exposed and age‐matched control animals, but the number of muscarinic receptor sites was 60 percent lower in the alcoholic animals. The present experimental model is consistent with altered food and water intake as consequences of chronic alcoholism and thus changes in food and water consumption may participate in mediating the effects of chronic alcohol intake on NMS binding sites. We suggest that the previously reported marked alcohol‐induced increase in pancreatic acetylcholine levels, which has been proposed to play a crucial role in the pathogenesis of acute alcoholic pancreatitis, may be a secondary phenomenon induced by increased resistance at the muscarinic recep

ISSN:0901-9928    

DOI:10.1111/j.1600-0773.1989.tb00664.x

出版商:Blackwell Publishing Ltd    

年代:1989

数据来源: WILEY