Lipid overload induced in myocardial cells by vegetable oils. Observation using electron microscopy]

Comparative studies were made to estimate the lipid overloading of myocardiac cells in rats fed by groups, for 3 and 6 days, one of the following dietary oils: peanut oil, maize oil, sunflower oi, soyabean oil, rapeseed-primor oil, rapeseed-canbra oil and rapeseed oil.     

Hypolipidemic effects of garlic oil in rats fed ethanol and a high lipid diet

Summary Feeding of ethanol and a high fat-high cholesterol diet to rats markedly increased the total lipids in the liver, and cholesterol and triglyceride levels in the serum, liver and kidneys. However, when ethanol mixed with 0.5% garlic oil was fed to animals maintained on the high fat-high cholesterol diet, these lipid levels were significantly reduced to levels near to those seen in untreated control rats. Garlic oil did not reduce the serum albumin or the total proteins of liver, kidneys or serum when fed along with ethanol. Probably the garlic oil enhances the catabolism of dietary cholesterol and fatty acids.The authors acknowledge with thanks the financial assistance of the University of Maiduguri for carrying out this project.     

Increase in Na+, K+ -ATPase enzyme units in liver and kidneys from essential fatty acid deficient rats.

(3H)-Ouabain binding to liver and kidney preparations was utilized to estimate the number of Na+, K+-ATPase enzyme units in livers and kidneys from rats fed 2% corn oil supplemented or fat-free diets. The specific (3H)-ouabain binding in liver and kidney preparations from fatty acid deficient rats was increased approximately 40%, but the affinity of the binding sites for ouabain (Kd-value) remained unchanged. The increased concentration of Na+, K+-ATPase enzyme units observed in the essential fatty acid deficient rats may contribute to the reduced body fat accumulation and elevated heat production observed in these animals.     

Certain biochemical effects of garlic oil on rats maintained on high fat-high cholesterol diet

The feeding of a high fat-high cholesterol (HF-HC) diet to normal rats for 1 month increased the lipid components cholesterol and triglyceride in serum, liver and kidneys and decreased the serum albumin very significantly. Administration of garlic oil (100 mg/kg b. wt/day) for 1 month together with the HF-HC diet to another group almost nullified the lipid-increasing and albumin-decreasing effects of that diet. The reduction in total lipids, cholesterol and triglycerides and the restoration to normal level of serum albumin were highly significant in the garlic oil group. Adipose tissue triglyceride lipase activity was significantly increased in both the above groups with a much greater rise in the oil group.     

Certain biochemical effects of garlic oil on rats maintained on high fat-high cholesterol diet

Summary The feeding of a high fat-high cholesterol (HF-HC) diet to normal rats for 1 month increased the lipid components cholesterol and triglyceride in serum, liver and kidneys and decreased the serum albumin very significantly. Administration of garlic oil (100 mg/kg b. wt/day) for 1 month together with the HF-HC diet to another group almost nullified the lipid-increasing and albumin-decreasing effects of that diet. The reduction in total lipids, cholesterol and triglycerides and the restoration to normal level of serum albumin were highly significant in the garlic oil group. Adipose tissue triglyceride lipase activity was significantly increased in both the above groups with a much greater rise in the oil group.     

超临界CO2萃取法提取库尔勒香梨精油及其成分分析研究

采用超临界CO2萃取法提取库尔勒香梨精油,用气相色谱-串联质谱技术对其成分进行分析,并对几种提取方法进行综合比较。结果表明,与水蒸气蒸馏法、固相微萃取法相比,超临界CO2萃取法具有香梨精油提取率最高,为0．0549％。感官分析的结果表明,超临界CO2萃取法所得的库尔勒香梨精油颜色为橙色透明液体,而且风味好。气相色谱-质谱联用（GC-MS）分析结果表明：超临界CO2萃取法所得的香梨精油中共鉴定出28种成分。丁酸乙酯、顺-7-十四烯-1-醇和乙酸己酯的含量最高,含量分别为5．19％、4．85％和4．37％。     

Differential expression of genes for uncoupling proteins 1, 2 and 3 in brown and white adipose tissue depots during rat development

The different expression patterns of genes for uncoupling proteins (UCPs) 1, 2 and 3 (ucp1, ucp2 and ucp3) were studied in interscapular brown adipose tissue (BAT) and in four white adipose tissue (WAT) depots (epididymal, inguinal, mesenteric and retroperitoneal) in male rats of different ages (18 days-12 months). UCP mRNA expression levels were determined by Northern blotting. In BAT, there were high levels of expression of UCP1 and UCP3 mRNA, but no detectable levels of UCP2 mRNA. Both ucp1 and ucp3 followed a similar expression pattern with age, with high levels in suckling rats which decreased to 50% or less in rats just under 2 months old, declining thereafter until 5 months and then recovering with age. However, an additional peak of expression was observed for ucp3 at the age of 3 months. In WAT, ucp1 expression was rare: occasional expression was found for UCP1 mRNA in the retroperitoneal depot in suckling rats and in the epididymal and inguinal depots in suckling and mature adult rats. ucp2 and ucp3 had different developmental expression patterns, but these were similar for each gene in the different depots studied. UCP3 mRNA was highly expressed in rats soon after birth, it decreased until 3 months, and increased thereafter, except for the mesenteric WAT where ucp3 expression decreased until 7 months before recovering. The fact that changes with age of both ucp1 and ucp3 expression have a similar profile in BAT, which is also similar to the ucp3 and also ucp1 profiles in some WAT depots, might reflect a common regulatory pattern for the expression of these genes, and also a common function. In contrast to ucp1 and ucp3, ucp2 had a peak of expression at about 2 months, and lower expression at 3 months, suggesting different regulation and probably a different role for this UCP.     

Effect of diabetes on the vertebral column of rats and its modification by estradiol

Summary In vertebrae of genetically selected sucrose-fed diabetic rats a statistically significant bone deficit was found after diabetes had been present for about 8 months. No osteopenia was observed in diabetic rats following treatment with estrogenic hormone for 5–7 months. The development of osseous centers in the end plates of the vertebrae was retarded in diabetic rats, but was about normal in diabetic rats given estrogen.—No differences were noted in the growth zones or in the tendency to develop articular lesions in rats of the various groups. Possible differences in the amount of GAG in intervertebral discs of diabetic and non-diabetic rats respectively await further confirmation.These investigations were aided by grant No. 2 RO1 EYO 1837-03, of the Institute of Arthritis and Metabolic Disease, National Institutes of Health, Bethesda, Maryland, USA.We are indebted to Professor Dr J. Rüttner, Institute of Pathology, University of Zürich, for his permission to use the calculator.     

50 ppm MnBK subclinical neuropathy in rats

Summary 40 rats were subjected daily for 6 months to an atmosphere containing 50 ppm MnBK. 32 of the rats presented with demyelination of the sciatic nerve and 2 of these with axonal hypertrophy.This work was supported in part by General Support Grant RR. 5414.We thank Dr Cedric Raines, Einstein Medical Center, New York, for helpful criticisms and suggestions and Dr Saul Francis for intoxicating the rats.     

Developmental and ageing changes in aminopeptidase activities in selected tissues of the rat

Aminopeptidase activities, assayed as arylamidase activities, were investigated in selected tissues of 1, 6, 12 and 24-month-old rats. The enzyme activities were found to have a heterogeneous distribution and age-related changes were observed. The highest levels of soluble arginyl-aminopeptidase activity were detected in brain homogenate at all the studied ages, whereas membrane-bound activity presented the highest levels in brain and kidney in the four ages tested. Aspartyl-aminopeptidase activity was detected mainly in the particulate fraction of kidney at all four ages. In 1, 6 and 12-month-old animals, soluble aspartyl-aminopeptidase activity was also higher in the kidney than in the rest of the tissues, whereas in the group of 2-year-old rats, the highest levels were found in both kidney and liver. Age-related changes were observed in all the studied tissues and for all the assayed enzymatic activities. In general, the maximal levels were detected in both the youngest and the oldest animals, and the minimal ones in 6 and 12-month-old rats. However, in the adrenals, the soluble and membrane-bound arginyl-aminopeptidase activity was higher in 6-month and 2-year-old rats than in 1-month and 12-month-old rats. These changes may reflect the functional status of the susceptible endogenous substrates of aminopeptidases.     

Methimazole treatment reduces cardiac hypertrophy and mortality without a concomitant reduction in blood pressure in established Goldblatt two-kidney one clip hypertension

The effects of methimazole, and antithyroid drug, on blood pressure and other parameters were evaluated in the established phase of Goldblatt two-kidney one clip (G2K-1C) hypertension. Methimazole was administered via drinking water for five weeks, starting five weeks after hypertension had been induced. After this period of treatment, similarly high blood pressures were observed in methimazole-treated and non-treated G2K-1C rats, despite the fact that a hypothyroid state had been achieved in methimazole-treated rats. Methimazole-treated G2K-1C rats showed reductions in heart rate, ventricular weight, ventricular/body weight ratio and mortality in comparison with rats not treated with methimazole. These results clearly demonstrate that hypothyroidism induced by methimazole: a) does not reverse G2K-1C hypertension, but b) improves the rate of survival and c) reduces relative cardiac hypertrophy, possibly by the reduction in cardiac work observed in Goldblatt hypothyroid rats.     

Methimazole treatment reduces cardiac hypertrophy and mortality without a concomitant reduction in blood pressure in established Goldblatt two-kidney one clip hypertension.

The effects of methimazole, an antithyroid drug, on blood pressure and other parameters were evaluated in the established phase of Goldblatt two-kidney one clip (G2K-1C) hypertension. Methimazole was administered via drinking water for five weeks, starting five weeks after hypertension had been induced. After this period of treatment, similarly high blood pressures were observed in methimazole-treated and non-treated G2K-1 C rats, despite the fact that a hypothyroid state had been achieved in methimazole-treated rats. Methimazole-treated G2K-1 C rats showed reductions in heart rate, ventricular weight, ventricular/body weight ratio and mortality in comparison with rats not treated with methimazole. These results clearly demonstrate that hypothyroidism induced by methimazole: a) does not reverse G2K-1 C hypertension, but b) improves the rate of survival and c) reduces relative cardiac hypertrophy, possibly by the reduction in cardiac work observed in Goldblatt hypothyroid rats.     

Age variation in the increase of hypothalamic and brain stem contents of phenylethanolamine m-octopamine and p-octopamine in spontaneously hypertensive rats (SH Kyoto).

Phenylethanolamine, m-octopamine and p-octopamine contents were determined as a function of age in the hypothalamus and brain stem of spontaneously hypertensive rats and controls Wistar Kyoto. In hypothalamus, the content of the 3 amines was 2--4-fold greater for the SH rats. In the brain stem, the phenylethanolamine and p-octopamine contents were 2--3-fold greater in SH rats but 5--6-fold higher in the case of m-octopamine. The difference appears at 3 weeks and correlates the blood pressure with the increase of age. The significance of these findings is discussed.     

Luteolytic potency of 16-phenoxy-derivatives of prostaglandin F2 alpha

The binding of 16-phenoxy derivatives of prostaglandin (PG) F2 alpha to rat luteal membranes, and also their abortifacient potency in pregnant rats, have been studied. Competitive binding studies with various PG-analogues were performed in ovaries of juvenile rats pretreated with PMSG and HCG, and in parallel studies the abortifacient potency of these substances was tested in pregnant rats. It was observed that this class of derivatives bound to the PGF2 alpha receptor as well as, or even better than the parent compound PGF2 alpha. Modifications in the carboxyl group at C-1 yielded derivatives with a higher affinity for the receptor, in decreasing order of effectiveness as follows: -COOR greater than COOH greater than OH. The data obtained from the binding studies also compared well with data on the abortifacient potency in pregnant rats. It is concluded that the addition of a phenoxy group to either the lower or upper side chain of PGF2 alpha may augment the binding to the receptor as well as the biological responses induced by the post receptor effect.     

Attenuation of diabetic retinopathy by the molecular chaperone-inducer amino acid analogue canavanine in streptozotocin-diabetic rats

The effect of canavanine treatment on the electroretinograms of healthy and streptozotocin-diabetic rats was studied. The characteristic amplitudes of the a-wave, W₂ and W₃ oscillatory potentials were markedly diminished in the 2-week streptozotocin-diabetic rats compared with those of the control rats. In contrast, the amplitudes of all the responses of the canavanine-pretreated streptozotocin-diabetic rats were practically indistinguishable from those of the control animals. Our results prompt further investigations for the use of amino acid analogues and other inducers of molecular chaperones in easing the chronic consequences of diabetes such as retinopathy. Received 3 June 1998; received after revision 14 August 1998; accepted 14 August 1998     

Synergism between long-acting bromocryptine microcapsules and cyclosporine A in the prevention of various autoimmune diseases in rats

Pre-treatment of male Sprague-Dawley rats with long-acting bromocryptine microcapsules (CBLA) significantly inhibited the arthritic response to Freund's complete adjuvant and reduced weight loss, thymolysis, splenomegaly and leukocytosis. In the prevention of adjuvant arthritis (AA), the combination of CBLA plus sub-optimal doses of cyclosporine A (CsA) was more efficient than either of the drugs alone. Sub-optimal doses of CsA were 0.1 and 1.0 mg/kg/day s.c. for 5 days. Furthermore, CBLA alone did not decrease the incidence of experimental allergic uveitis (EAU) in the male Lewis rats. Low-dose CsA reduced the incidence of uveitis by 50%, and with the addition of CBLA, 100% of rats were protected. Low-dose CsA was 2 mg/kg/day i.m. for 14 days. Long-term treatment of male Sprague-Dawley rats with CBLA alone reduced the incidence and severity of spontaneous autoimmune periateritis nodosa (PN) in a dose-dependent manner; CsA was less potent than CBLA, and only additive effects were obtained. Finally, for the prevention of spontaneous autoimmune insulin-dependent diabetes (DM), the administration of CBLA did not improve the effect of a low-dose CsA in male BB rats. Nevertheless, a delay in onset of DM could be achieved. A sequential therapy using CsA plus CBLA clearly showed beneficial effects. The dose of CsA was 10 mg/kg p.o. 6 days/week for 21 weeks. Compared with Sprague-Dawley or Lewis male rats, BB male rats showed only weak prolactin suppression after the same doses of CBLA. It is suggested that the use of CBLA may be particularly beneficial in autoimmune disorders. The effectiveness of the combination therapy CBLA plus CsA, however, was dependent on the model considered. Various factors could play a role: (1) the different ways of administering CsA (s.c. in AA, i.m. in EAU and PN, oral in DM); (2) strain-dependency in the capacity of CBLA to suppress Prl secretion; and(3) at least in the BB rats, the transient increase of CsA bioavailibility which was possibly induced by CBLA.     

内源性硫化氢与皮质发育障碍模型大鼠认知功能损害的相关性研究。

目的探讨皮质发育障碍DCDs（disorders of cortical development）模型鼠的认知功能与H2s的变化关系。方法用1射线照射孕15d Wistar大鼠,制作DCDs模型。采用Morris水迷宫法测试P30（出生后30天）、P60、P90F1代DCDs模型鼠和对照组大鼠的学习能力和空间记忆能力。用敏感硫电极法检测大鼠血液及海马组织中H2s浓度。用亚甲基蓝法测定大鼠海马神经元细胞胱硫醚,B-合酶CBS（cystathionine。beta-synthase）酶活性。结果水迷宫实验：P60、P90模型组大鼠较正常对照组潜伏期明显延长（P〈0．05）,且随月龄增加潜伏期越长。P60、P90模型纽大鼠较对照组血液也s浓度分别降低6．5、11．5μmol,／L、海马组织H2s含量分别减少3．2、5．6μLmol／L．mg,海马组织神经元细胞CBS酶活性降低24．94、34．46μmol／L．g．min。P30模型组与对照组的各项变化不明显。结论DCDs模型鼠脑内H,S含量及海马组织神经元细胞CBS酶活性降低,内源性H2s降低与DCDs认知功能损害可能具有相关性,并为治疗皮质发育障碍的认知功能损害可能提供治疗途径。     

Age variation in the increase of hypothalamic and brain stem contents of phenylethanolamine m-octopamine and p-octopamine in spontaneously hypertensive rats (SH kyoto)

Summary Phenylethanolamine, m=octopamine and p-octopamine contents were determined as a function of age in the hypothalamus and brain stem of spontaneously hypertensive rats and controls Wistar Kyoto. In hypothalamus, the content of the 3 amines was 2–4-fold greater for the SH rats. In the brain stem, the phenylethanolamine and p-octopamine contents were 2–3-fold greater in SH rats but 5–6-fold higher in the case of m-octopamine. The difference appears at 3 weeks and correlates the blood pressure with the increase of age. The significance of these findings is discussed.This work has been completed at the Tokyo University. The author is grateful to Professor Z. Tamura, Dr K. Imai and A. Ooshima as well as to the French Foreign Office and the Japanese Society for the Promotion of Sciences.     

Les glycoprotéines sériques dans le granulome expérimental provoqué par la carrageenine

Summary We studied serum glycoproteins in rats and guinea pigs during the development of granulomas, provoked by carrageenin injection. In rats total serum sialic acid was raised as well as sialic acid soluble in sulfosalicylic acid and haptoglobin. The rise of these 2 fractions, seromucoid and haptoglobine accounts quantitatively for the rise of the total sialic acid. In guinea pigs total serum sialic acid was unchanged, but sulfosalicylosoluble sialic acid as well as haptoglobin were much higher than basal values. Quantitatively the serum glycoprotein reaction was much higher in rats than in guinea pigs.     

Studies on chemically induced tumors in rats: I. Heterogeneity of tumor cells and establishment of syngeneic, tumor-specific cytotoxic T cell clones

Sarcoma P1 was induced in DA rats by DMBA. Anti-P1 antibodies were produced in DA rats, purified via fixed tumor cells and used to induce anti-idiotypic antibodies in syngeneic rats. The anti-idiotypic antibodies were used to generate cytotoxic, P1 specific DA T cells in vitro. These cytotoxic T cells and P1 tumor cells were cloned by limiting dilution. Using the DA anti-P1 specific cytotoxic T cell clones, we were able to characterize 2 types of P1 tumor cell clones, namely those which were susceptible and those which were resistant to the P1 specific cytotoxic T cells. Cytotoxic T cell injected i.v. into syngeneic DA rats could not prevent the development of lethal P1 tumors.