Comparative biochemistry and physiology. C, Comparative pharmacology and toxicology最新文献

1. Four groups of rats were injected with four different anti-inflammatory drugs (indomethacin, phenylbutazone, acetylsalicylic acid and hydrocortisone) and the activities of superoxide dismutase, catalase and glutathione peroxidase were studied in the liver and kidney. 2. The drugs treatment resulted in decreased activity of the enzymes in both organs compared to the control animals. 3. In vivo tissue peroxidation was also effected by the drugs used. 4. Our results indicate that the changes of oxygen free-radical metabolism contribute to the action of these drugs in vivo.

1. This study was designed to investigate the clomiphene or tamoxifen binding to receptor sites for estradiol-17 beta (E2R) and estriol (E3R) in the rabbit uterus. 2. Those so-called anti-estrogenic compounds tended to inhibit E2-E2R and E3-E3R bindings equally. 3. The inhibitor constant of clomiphene for E2R was approximately 3.8 x 10(-8) M at 4 degrees C and that for E3R approximately 1.8 x 10(-8) M at 4 degrees C in a given case, determined by charcoal assay. 4. It is suggested that the anti-estrogenic compounds demonstrate their effects after binding either to E2R or to E3R. 5. There were some tissue differences of the contents between E2R and E3R. For example, the uterus and the cortex contained E2R, and the pituitary E3R more than the other.

1. After selective binding of [3H]pargyline to either monoamine oxidase (MAO) A or MAO B in the rat liver, MAO B alone in the rat brain and MAO in carp brain and liver, molecular weight and isoelectric points (pI) of these MAO were determined by sodium dodecyl sulphate (SDS)-polyacrylamide gel electrophoresis and isoelectric focusing and results obtained were compared. 2. For all tissues tested, SDS-polyacrylamide gel electrophoresis of [3H]pargyline-bound samples revealed a labelled protein band of an apparent mol. wt of 60,000 da. 3. Estimation of radioactivity of [3H]pargyline bound after isoelectric focusing revealed a single protein band with acidic pI values of about 5.5 for rat brain and liver MAO B. 4. Moreover, the pI values of about 7.5 were obtained for carp brain and liver MAO. This basic value was also found for MAO A in the rat liver MAO A.

1. Five sheep were used to investigate the influences of alpha-adrenergic subtype receptor blockade on the secretion of both glucagon and insulin. 2. The glucagon secretion was stimulated through an alpha 2-adrenergic subtype mechanism. 3. The secretion of insulin was inhibited by an alpha 2-adrenergic subtype mechanism in conscious sheep.

1. The effects of isoprenaline on the release of transmitter substances from perivascular adrenergic nerves were estimated from the excitatory junction potential (ejp) and outflow of noradrenaline in the dog mesenteric vein. 2. Isoprenaline increased the ejp amplitude and decreased the evoked release of noradrenaline. Yohimbine potentiated the former and converted the latter to an increased outflow. 3. Therefore, stimulation of prejunctional beta-adrenoceptor by isoprenaline increases the release of noradrenaline from perivascular adrenergic nerves. 4. Possible involvement of prejunctional alpha-adrenoceptors in the isoprenaline-induced modulation of transmitter release was also suggested.

1. Accumulation of 2,4,6-trichlorophenyl-4'-aminophenyl ether (CNP-amino) in carp was investigated for 14 days. CNP-amino in carp could be divided into free CNP-amino [CNP-amino(I)] and bound CNP-amino [CNP-amino(II)]. 2. The bioconcentration factors (BCF) of CNP-amino(I + II) in carp were 90 +/- 38 (mean +/- SD, n = 3) for muscle, 402 for liver, 501 for kidney and 5368 for gallbladder after 14 days exposure. 3. 2,4,6-Trichlorophenyl-4'-acetamide phenyl ether (CNP-acetamide) was detected as metabolites of CNP-amino in muscle and viscera of carp.

1. Bioconcentration and excretion of diazinon, IBP, malathion and fenitrothion were studied for carp (Cyprinus carpio L.). 2. The concentrations of these pesticides in muscle and viscera of the carp reached plateaus in 12-48 hr exposure. 3. The average values of bioconcentration factors (BCF) for diazinon were 20.9 in muscle, 60.0 in liver, 111.1 in kidney and 32.2 in gallbladder over the 168 hr exposure period. Similarly, those values were 4.3-26.7 for IBP, 2.7-17.3 for malathion, and 36.0-157.1 for fenitrothion. 4. The excretion rate constants of malathion (hr-1) were 0.13 for muscle, 0.12 for liver, 0.08 for kidney and 0.06 for gallbladder. Those of diazinon, IBP and fenitrothion (g.ng-1.hr-1) were 0.002-0.024 for muscle, 0.001-0.020 for liver, 0.0004-0.004 for kidney and 0.002-0.023 for gallbladder, respectively.

1. Wistar rats of both sexes daily received an ethanol solution of ammonium metavanadate (AMV) of 0.3 mg V/cm3 5% ethanol concentration as sole drinking liquid, for a period of 4 weeks. 2. The reference groups received for drinking aqueous AMV solution, or 5% ethanol, or water. 3. In animals drinking both water and ethanol AMV solution a decrease in the erythrocyte count and haemoglobin level was noted together with an increase of the percentage of reticulocytes and polychromatophilic erythrocytes in the peripheral blood. 4. A small rise of the percentage of polychromatophilic and orthochromatic erythroblasts was at the same time noted in the bone marrow of animals receiving ethanol AMV solution. 5. In the group of animals drinking 5% ethanol a fall of the erythrocyte count was observed and a rise of the leukocyte count, particularly of lymphocytes. 6. Substitution of water by 5% ethanol solution as solvent for AMV did not have any distinct influence on the toxicity of the tested compound.

1. Repeated oral administrations of tryptic hydrolysate of bovine milk casein (CEI) showed antihypertensive effect in spontaneously hypertensive rats. 2. Single oral administration of CEI antagonized the pressor response to angiotensin I. 3. Bovine milk casein hydrolysate inhibited the angiotensin I-converting enzyme (ACE) activity. Three peptides with ACE-inhibiting activity were isolated from CEI. 4. It is suggested that ACE-inhibiting peptides in the tryptic hydrolysate milk casein are absorbed from the intestinal tract and produce an antihypertensive effect.