Neuroprotection of nerve growth factor-loaded microspheres on the D2 dopaminergic receptor positive-striatal neurones in quinolinic acid-lesioned rats: a quantitative autoradiographic assessment with iodobenzamide.

Huntington's disease (HD) results from the degeneration of striatal neurones, mainly gamma-aminobutyric acid (GABA)ergic projection neurones and lately cholinergic interneurones. The use of trophic factors as agents able to prevent such neural degeneration is a promising strategy. The aim of this study was to validate nerve growth factor-loaded (NGF-loaded) poly-D,L-lactide-co-glycolide (PLGA) microspheres for treatment of HD in a rat model with quinolinic acid lesion using autoradiographic study of D2 dopaminergic receptors (D2R). This target is expressed by about half of striatal neurones and its scintigraphic exploration has already been performed for the follow-up of this degenerative process. Ex vivo autoradiography of D2R performed with iodobenzamide, the widely used ligand for single photo emission computerized tomography, revealed slight neuroprotection. Moreover, tolerance of microspheres was demonstrated by in vitro autoradiography with the marker of gliosis, [(3)H]-PK 11195.

Quantification of alpha 1-adrenoceptor subtypes in human tissues by competitive RT-PCR analysis.

Alpha 1-Adrenoceptors are a heterogeneous subfamily of receptors comprising at least three pharmacologically- and structurally- distinct subtypes named alpha 1a-, alpha 1b- and alpha 1d-adrenoceptors. A competitive reverse transcription-polymerase chain reaction methodology using subtype selective competitor RNAs as reference internal standards was adopted to determine the absolute amounts of each of the three cloned to date alpha 1-adrenoceptor subtype encoding mRNAs in selected human tissues. Our data demonstrated that each of these alpha 1-adrenoceptor subtypes exhibits a distinctive tissular expression pattern.