Fig. 3
High-affinity NT receptor involvement in NT-polyplex-mediated expression of the gene encoding chloramphenicol acetyl transferase. NT-polyplex-pSV2cat was microinjected into the pars compacta of the substantia nigra and into the molecular layer of the ansiform lobule of the cerebellum, where high-affinity NT receptors are absent. The figure is a representative autoradiography from three independent experiments showing a thin layer chromatography of [14C]-chloramphenicol enzymatic acetylation. CAT gene expression in lysates from N1E-115 cells transfected with pSV2cat by the DNA-CaPO4 co-precipitation technique was used as a positive control of the CAT assay (lane A). CAT activity in supernatants from homogenates of the entire pars compacta of the substantia nigra in the absence (lane B) or presence of SR-48692 (lane C). Neither homogenates from tissue over the polyfected substantia nigra pars compacta (lane D) nor those from the polyfected molecular layer of the ansiform lobule of the cerebellum (lane E) had detectable CAT activity.