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SG Volsen NC Day AL McCormack W Smith PJ Craig RE Beattie D Smith PG Ince PJ Shaw SB Ellis N Mayne JP Burnett A Gillespie MM Harpold 《Canadian Metallurgical Quarterly》1997,80(1):161-174
The beta subunits of voltage-dependent calcium channels, exert marked regulatory effects on the biophysical and pharmacological properties of this diverse group of ion channels. However, little is known about the comparative neuronal expression of the four classes of beta genes in the CNS. In the current investigation we have closely mapped the distribution of beta1, beta2, beta3 and beta4 subunits in the human cerebellum by both in situ messenger RNA hybridization and protein immunohistochemistry. To our knowledge, these studies represent the first experiments in any species in which the detailed localization of each beta protein has been comparatively mapped in a neuroanatomically-based investigation. The data indicate that all four classes of beta subunits are found in the cerebellum and suggest that in certain neuronal populations they may each be expressed within the same cell. Novel immunohistochemical results further exemplify that the beta voltage-dependent calcium channel subunits are regionally distributed in a highly specific manner and studies of Purkinje cells indicate that this may occur at the subcellular level. Preliminary indication of the subunit composition of certain native voltage-dependent calcium channels is suggested by the observation that the distribution of the beta3 subunit in the cerebellar cortex is identical to that of alpha(1E). Our cumulative data are consistent with the emerging view that different native alpha1/beta subunit associations occur in the CNS. 相似文献
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PURPOSE: To evaluate the feasibility of introducing exogenous genes and phosphorothioate oligonucleotides into the anterior chamber tissues of rats and monkeys using the authors' fusogenic liposomes. METHODS: Hemagglutinating virus of Japan liposomes containing LacZ DNA-high-mobility group 1 complexes or fluorescein isothiocyanate (FITC)-labeled phosphorothioate oligonucleotides were prepared and injected into the anterior chambers of rats (3 microliters) and rhesus monkeys (30 microliters). The expression of LacZ DNA was visualized histochemically by beta-Galactosidase assay and was followed for as long as 60 days in rats and 30 days in monkeys. FITC-labeled phosphorothioate oligonucleotides were observed by fluorescence microscopy for as long as 14 days in rats and 7 days in monkeys. RESULTS: Injection of LacZ DNA-high-mobility group 1 complexes encapsulated in hemagglutinating virus of Japan liposomes resulted in blue staining in the trabecular meshwork and iris-ciliary body of rats and selectively in the trabecular meshwork of monkeys at the concentrations used. This LacZ expression lasted for as long as 14 days after injection in both animals. Phosphorothioate oligonucleotides (3 microM) also were introduced into the rat trabecular meshwork and iris-ciliary body and into the primate trabecular meshwork when encapsulated in hemagglutinating virus of Japan liposomes, although the injection of naked FITC-labeled phosphorothioate oligonucleotides at the same concentration resulted in little fluorescence in any anterior chamber tissue. CONCLUSIONS: This study shows that the use of hemagglutinating virus of Japan liposomes can transfer LacZ DNA and phosphorothioate oligonucleotides to adult rat and primate trabecular meshwork. This system may enable progress in glaucoma research and in the development of nonviral somatic gene therapy of the trabecular meshwork to treat glaucoma. 相似文献
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