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71.
In vivo effects of some histamine H1-receptor antagonists on monoamine metabolism in the mouse brain 总被引:2,自引:0,他引:2
Setsu Shishido Ryozo Oishi Kiyomi Saeki 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):185-189
Summary The in vivo effects of four Hr-antagonists, diphenhydramine, chlorpheniramine, mepyramine, and promethazine, on the metabolism of noradrenaline (NA), dopamine (DA), and 5-hydroxytryptamine (5-HT) were investigated in the whole mouse brain. Diphenhydramine and chlorpheniramine had no significant effect on levels of NA, 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), DA, and 5-HT, but they significantly decreased levels of 3,4-dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA), and 5-hydroxyindoleacetic acid (5-HIAA). In particular chlorpheniramine markedly decreased 5-HIAA levels at doses as low as 1 mg/kg, i. p. Mepyramine significantly decreased 5-HIAA levels but not those of other substances. High doses of promethazine significantly decreased NA levels but markedly increased those of MHPG, DOPAC, HVA, 5-HT, and 5-HIAA. The DA reduction induced by -methyl-p-tyrosine (-MT) was significantly inhibited by diphenhydramine, chlorpheniramine, and promethazine, but the -MT-induced NA decrease was significantly enhanced by promethazine. The 5-HIAA accumulations induced by probenecid were significantly inhibited by chlorpheniramine and mepyramine. These results suggest: (1) Diphenhydramine and chlorpheniramine inhibit the turnover of both DA and 5-HT by blocking their neuronal uptake. (2) Promethazine and mepyramine inhibit DA and 5-HT turnover, respectively, as a result of the inhibition of the uptake mechanism. (3) Promethazine increases NA turnover by enhancing NA release. The discriminative effects of these drugs on the monoamine systems may be related to some differences in their CNS actions.
Send offprint requests to K. Saeki at the above address 相似文献
72.
Noboru Toda Kazuhide Yoshida Tomio Okamura 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):221-224
Summary Dog temporal artery strips without endothelium responded to transmural electrical stimulation with a contraction which was potentiated by NG-nitro-l-arginine (l-NNA). The noradrenaline-induced contraction and the release of 3H-noradrenaline were not affected. The stimulation-induced contraction was reversed to a relaxation by phentolamine. The relaxation was not influenced by timolol and atropine but inhibited by l-NNA; l-arginine abolished the inhibition. Transmural stimulation released NOx from the arteries, the release being abolished by l-NNA. Potentiation by l-NNA of the neurally-induced contraction appears to be due to elimination of NO produced by non-adrenergic, non-cholinergic vasodilator nerve activation.
Send offprint requests to N. Toda at the above address 相似文献
73.
Takashi Uno Jun Itami Takeki Shiima Takafumi Toita Syuichi Mikuriya Kazuo Hatano Noboru Arimizu 《Cancer chemotherapy and pharmacology》1992,31(Z1):S106-S110
From April 1978 through December 1989, a total of 17 patients with unresectable hepatocellular carcinoma (HCC) were treated with radiation therapy alone or radiation therapy in conjunction with percutaneous ethanol injection (PEI), transarterial infusion chemotherapy (TAI), or transarterial embolization (TAE) at the National Medical Center Hospital. The median survival of all patients was 13.8 months. The survival values determined at 1, 2, and 3 years were 58.8%, 26.1%, and 9.8%, respectively. Only the pretreatment liver function affected the survival value. Between patients who did not have liver cirrhosis (LC) as well as those who had LC of Child's class A and patients who had LC of Child's class B or C, the differences observed in the 1-year survival value and the median duration of survival were statistically significant (P<0.05). the=" serum=" cholinesterase=" (che)=" level=" seemed=" to=" be=" a=" good=" indicator=" of=" liver=" function=" during=" the=" radiation=" therapy.=" a=" field=" size=" of=" 150=">0.05).>2 and a total dose of 5000 cGy (TDF 82) seemed to be well tolerated by patients who did not have LC and those who had LC of Child's class A. The field size determined whether patients with poor liver function such as LC of Child's class B or C would develop severe hepatic deterioration after undergoing radiation therapy.Presented at The Second International Symposium on Treatment of Liver Cancer. Taipei, 3–4 February 1991 相似文献
74.
In order to clarify the interaction of volatile anesthetics and extracellular calcium ion on the myocardial contraction, effects of both isoflurane (1.0%) and halothane (0.5%) on the extracellular calcium ion concentration ([Ca2+]O)-tension curve were studied. Increasing [Ca2+]O enhanced the myocardial contraction response, and the maximal response was obtained at [Ca2+]O of 3.0mM. Halothane depressed the maximal value of the tension development in response to increasing [Ca2+]O, while isoflurane did not (P 0.01). The probit response of the developed tension to the changes in [Ca2+]O indicated that isoflurane increased the median effective concentration (EC50) of [Ca2+]O significantly from 0.484 ± 0.051 (mean ± SEM) to 0.870 ± 0.056mM (P = 0.001), but halothane did not (P = 0.018). Therefore, 1.0% isoflurane was concluded to move the [Ca2+]O-tension curve to the right, while a downwards shift occurred with 0.5% halothane.(Saeki S, Hirakawa M, Shimosato S: Effects of Isoflurane and Halothane on the Calcium Ion-tension Curve in Rat Myocardium. J Anesth 6: 172–175, 1992) 相似文献
75.
Hirohito Yano Takashi Funakoshi Jun Shinoda Noboru Sakai George Kokuzawa Kuniyasu Shimokawa 《Brain tumor pathology》1997,14(1):75-78
A 35-year-old woman had an intradural tumor in the posterior fossa adjacent to the posterior wall of the left pyramidal bone,
which was totally removed and histologically diagnosed as a pleomorphic adenoma. Follow-up examination for 2 years showed
no recurrence of the tumor. There was no primary lesion in any other gland of the body, and therefore there is no alternative
but to conclude a “migration” of some gland cells. The pathogenesis of this tumor remains unclassified. 相似文献
76.
77.
Proliferation, Vascular Endothelial Growth Factor Expression and Cavernous Sinus Invasion in Growth Hormone Secreting Pituitary Adenomas 总被引:4,自引:0,他引:4
Summary Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus
(CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular
endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance
of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade
3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67
expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels.
The Ki-67 index of high MR grade adenomas (1.17±0.62%) was significantly higher than that of low MR grade adenomas (0.55±0.42%,
p=0.027), whereas VEGF expression showed no significant correlation with MR grades (p>0.999). Tumour volume also showed a
significant correlation with MR grade (p=0.002). VEGF expression was not correlated with serum hormone level and volume, but
was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors
related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a
role in activation of tumour aggressiveness, which is required in CS invasion.
Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome,
pre-operative medical debulking is indicated, particularly, in such adenomas. 相似文献
78.
79.
灵芝多糖对小鼠脾脏树突状细胞的增殖作用 总被引:5,自引:0,他引:5
目的 观察灵芝多糖(GP)对小鼠脾脏树突状细(dendrirtie cells,DCs)的增殖作用。方法采用MTT法,以细胞因子(GM-CSF+IL-4)作比较,观察不同质量浓度GP以及细胞因子+不同浓度的GP对小鼠脾脏DCs的增殖作用。结果GP(5-80μg/mL)可明显刺激小鼠脾脏DCs增殖,与细胞因子组相比,其较高质量浓度组(20、40、80μg/mL)作用明显;GP+细胞因子,与对照组相比均有显著的增殖作用,且明显高于细胞因子组。结论GP不仅能促进小鼠脾脏DCs的增殖,而且与细胞因子有显著的协同作用。具有类生长因子和协同生长因子的作用。 相似文献
80.
Daisuke Tamanoi Koichi Saruwatari Kosuke Imamura Ryo Sato Takuya Jodai Shohei Hamada Yusuke Tomita Sho Saeki Shikiko Ueno Yuji Yonemura Hidenori Ichiyasu Takuro Sakagami 《Internal medicine (Tokyo, Japan)》2022,61(11):1731
The effect of radiotherapy during immunotherapy on immune-related adverse events (irAEs) is not fully understood. We herein report a 74-year-old woman diagnosed with lung adenocarcinoma with programmed death ligand 1 expression ≥50% and treated with pembrolizumab. She developed fatal immune thrombocytopenia associated with pembrolizumab immediately following radiotherapy. A flow cytometry analysis of peripheral blood detected an increased expression of programmed death-1 (PD-1) and Ki-67 in CD4+ and CD8+ T cells after radiotherapy, compared with pre-irradiation measurements. This case suggests that radiotherapy may evoke irAEs during treatment with anti-PD-1 antibodies, which physicians should consider when using radiotherapy in patients treated with these drugs. 相似文献