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A.M. Ageel K.E.H. El-Tahir A.R. Abu-Jayyb 《Prostaglandins & other lipid mediators》1985,30(3):369-381
The effect of bromocriptine mesylate on cyclic nucleotides and PGI2 release by rat aortic and uterine tissues was investigated. Treatment of rats with bromocriptine (10 mg kg−1 I.P. daily for 14 days) increased PGI2 release by the thoracic aorta from 0.67 ± 0.02 to 1.4 ± 0.03 ng/mg wet tissue (P < 0.001; n = 6). This increase was antagonized by treatment with sulpiride (15 mg kg−1). Incubation of the arterial tissue with bromocriptive (50 ug ml−) in vitro also stimulated PGI2 release. Mepacrine (160 μg ml−) significantly decreased both basal and stimulated PGI2 release. Incubation of myometrial tissue from pregnant rats with bromocriptine (50 μg ml−1) in vitro significantly decreased PGI2 release from 1.25 ± 0.07 to 0.60 ± 0.08 ng/mg wet tissue (P < 0.05, n = 6).It also elevated uterine cAMP from 40 ± 2 to 64 ± 3 pmoles/100 mg wet tissue. Both effects were antagonized by sulpiride. Bromocriptine did not affect uterine cGMP or the cyclic nucleotides in the aorta. It is concluded that the increase in aortic PGI2 was mediated via activation of dopamine D-2 receptors that stimulate phospholipase A2 enzyme. The decrease in myometrial PGI2 release may be related to the increase in uterine cAMP resulting from activation of dopamine D-1 receptors. Previous studies suggested a role for PGI2 in implantation in the rat. The results suggest that the inhibitory effèct on uterine PGI2 may underlie the reported inhibition of bromocriptine on implantation. On broad basis, the decrease in uterine PGI2 together with the reported luteolytic effect of bromocriptine point to a potential role for the compound in postcoital contraception. 相似文献
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Adenine uptake by isolated rat thymocytes 总被引:1,自引:0,他引:1
P H Cartier 《The Journal of biological chemistry》1980,255(10):4574-4582
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K N Iarygin A N Kazimirski? G I Kositski? A Iu Rubina V A Vinogradov 《Biulleten' eksperimental'no? biologii i meditsiny》1986,101(6):680-682
The authors studied the anabolic effect of peptide morphogen of the hydra undecapeptide on normal and regenerating rat liver. Ornithine decarboxylase (EC 4.1.1.17) activity served as a marker. Intraperitoneal injection of the peptide into intact animals stimulated ornithine decarboxylase activity in a dose-dependent manner. In partially hepatectomized rats the peptide stimulated ornithine decarboxylase activity in the dose of 20 micrograms/kg body weight while greater doses inhibited the enzyme activity. 相似文献
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RNA was degraded at 60 degrees C for 24 h by halophilic nuclease H in supernatants from broth cultures of Micrococcus varians subsp. halophilus containing 12% NaCl. Since contaminating 5'-nucleotidase exhibited almost no activity under these conditions, the 5'-GMP formed could be recovered from the reaction mixture, and the yield was 805 mg from 5 g of RNA. 相似文献
230.
Immune deficiency in the X-linked lymphoproliferative syndrome. I. Epstein-Barr virus-specific defects 总被引:8,自引:0,他引:8
S Harada K Sakamoto J K Seeley T Lindsten T Bechtold J Yetz G Rogers G Pearson D T Purtilo 《Journal of immunology (Baltimore, Md. : 1950)》1982,129(6):2532-2535
Eleven males with XLP were evaluated for EBV-specific antibodies during periods of 2 to 7 yr. Variable responses to EBV-specific antigens were found. All 11 patients had subnormal anti-EBNA titers, which probably reflected a T cell deficiency. The patients showed four different patterns in their anti-VCA response: 1) two boys who had experienced malignant lymphoma mounted no antibodies at all; 2) two patients showed intermittent anti-VCA titers; 3) four males had persistently elevated anti-VCA titers; and 4) three patients showed normal anti-VCA titers. ADCC against EBV-infected cells was abnormally low in six patients and was elevated in two patients given gamma-globulin. ADCC titers did not correlate with anti-VCA titers. However, most patients with XLP failed to effect regression of autologous EBV-infected lymphoblastoid cell lines, indicating a deficiency in long-lived T cell-mediated immunity to EBV. 相似文献