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391.
392.
F V DeFeudis L M Orensanz Mu?oz M A Vidal G Corrochano M Sanchez del Alamo 《Experientia》1978,34(9):1169-1170
High-affinity, Na+-independent binding of beta-alanine to a synaptosomal fraction of rat brain was potently inhibited by glycine and by some other alpha-amino acids, but not by taurine or GABA. This binding mechanism, which was also sensitive to both bicuculline and strychnine, might involve synaptic receptors for both beta-alanine and glycine. 相似文献
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K J Mikolajczak R V Madrigal J K Rupprecht Y H Hui Y M Liu D L Smith J L McLaughlin 《Experientia》1990,46(3):324-327
Sylvaticin (I), a new tetrahydroxy annonaceous acetogenin with nonadjacent tetrahydrofuran rings, has been isolated from the dried fruits of Rollinia sylvatica St. Hil. (Annonaceae). This compound is extremely cytotoxic to human tumor cells and shows promising insect control properties. 相似文献
396.
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P. Milner V. Ralevic A. M. Hopwood E. Fehér J. Lincoln K. A. Kirkpatrick G. Burnstock 《Cellular and molecular life sciences : CMLS》1989,45(2):121-125
Substance P and choline acetyltransferase have been localised in a small proportion of endothelial cells of rat coronary arteries using electron microscopic immunocytochemistry. During a hypoxic period of 1 min, coronary vasodilatation was produced in the Langendorff heart preparation and increased levels of substance P and acetylcholine were released into the perfusate. The possibility that these substances are released from endothelial cells during hypoxia and contribute to the hyperaemic response is discussed. 相似文献
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Alexander V. Zhdanov Ruslan I. Dmitriev Dmitri B. Papkovsky 《Cellular and molecular life sciences : CMLS》2011,68(5):903-917
Bafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12
(dPC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in dPC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and ΔΨm. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect
of Baf on the ΔΨm. Baf induces stochastic flickering of the ΔΨm with a period of 20 ± 10 s. Under conditions of suppressed
ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels.
Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a
number of (patho)physiological conditions induced by Baf. 相似文献