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861.
R. Christopher Pierce Amy J. Clemens Laura A. Shapiro George V. Rebec 《Psychopharmacology》1994,116(1):103-109
Acute administration of neuroleptic drugs alters the extracellular level of ascorbate in the neostriatum, and increasing evidence suggests a role for this vitamin in the behavioral, and possibly therapeutic, effects of these drugs. To shed further light on this issue, extracellular ascorbate was recorded in the neostriatum and nucleus accumbens of awake, behaving rats following chronic treatment with either classical (haloperidol) or atypical (clozapine) neuroleptics or ascorbate itself. Electrochemically modified, carbon-fiber microelectrodes were lowered in place the day after the last of 21 daily injections of either haloperidol (0.5 mg/kg, SC), clozapine (20 mg/kg, IP), sodium ascorbate (500 mg/kg, IP) or vehicle. Voltammetric measurements were obtained during quiet rest and following administration ofd-amphetamine (2.5 mg/kg). Repeated treatment with either haloperidol or ascorbate elevated basal extracellular ascorbate and potentiated the amphetamine-induced increase in ascorbate release in neostriatum but not nucleus accumbens. Both treatment groups also showed a significant increase in amphetamine-induced sniffing and repetitive head movements compared to vehicle-treated animals. In contrast, repeated clozapine had no effect on extracellular ascorbate in either neostriatum or nucleus accumbens, but increased the locomotor response to an amphetamine challenge. Thus, to the extent that increases in neostriatal ascorbate exert neuroleptic-like effects, such effects are likely to parallel haloperidol rather than clozapine. 相似文献
862.
Zh. A. Mamyrbekova S. A. Soldatova V. I. Abelentsev T. I. Solov'eva V. N. Guryshev A. T. Soldatenkov 《Pharmaceutical Chemistry Journal》1994,28(3):198-202
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 28, No. 3, pp. 48–51, March, 1994. 相似文献
863.
É. T. Oganesyan S. Kh. Chomaeva A. V. Ivchenko L. S. Sarkisov 《Pharmaceutical Chemistry Journal》1994,28(10):759-762
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 28, No. 10, pp. 53–56, October, 1994. 相似文献
864.
V. I. Nifontov N. P. Bel'skaya E. A. Shtokareva 《Pharmaceutical Chemistry Journal》1994,28(10):687-706
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 28, No. 10, pp. 4–18, October 1994. 相似文献
865.
M. M. Kozlovskaya S. V. Nikitin A. Gochmuradov L. D. Smirnov 《Pharmaceutical Chemistry Journal》1994,28(10):715-719
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 28, No. 10, pp. 23–26, October, 1994. 相似文献
866.
867.
868.
A rapid and sensitive method for measuring monooxygenase activities in hepatocytes cultured in 96-well plates 总被引:3,自引:0,他引:3
Summary Measurement of biotransformation activities in cells is of great importance for drug metabolism and toxicologic studies. It is currently done by measuring the enzymatic activities in partially purified microsomes. In the present work we report on a rapid, easy, sensitive, and reproducible fluorimetric assay for quantifying cytochrome P450-dependent monooxygenase activities (P450IA1, P450IIB1) in hepatocytes cultured in 96-well plates. The procedure involves the direct determination of enzymatic activities in intact hepatocytes while avoiding cell homogenization, thereby permitting use of a the reduced number of cells and allowing cultured cells to be used in later experiments. Substrates (7-ethoxyresorufin, 7-pentoxyresorufin) are added to culture medium and metabolized by hepatocytes. After enzymatic deconjugation, the fluorescent resorufin present in culture medium is quantified by means of a microplate fluorimetric reader. Major advantages of this technique, as compared to other available methods, are: a) no cell disruption is required; b) activity can be measured with a very small number of cells; c) rapid processing time; and d) possibility of performing repeated assays with the same cell monolayer. 相似文献
869.
B. B. Aleksandrov M. S. Gavrilov R. Z. Dautova R. Kh. Niyazov V. D. Sviridov N. D. Chkanikova B. Ya. Syropyatov V. S. Shklyaev Yu. V. Shklyaev 《Pharmaceutical Chemistry Journal》1992,26(1):57-58
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 26, No. 1, pp. 44–45, January, 1992. 相似文献
870.