Expression of platelet-derived growth factor after intrastriatal ibotenic acid injury

The expression of platelet-derived growth factor (PDGF) was studied in a rat model of Huntington's disease, produced by unilateral intrastriatal ibotenic acid injections. The most pronounced effect registered was that the number of PDGF-immunoreactive cells increased in the lesioned area up to 10 weeks after the surgery. Double immunofluorescence staining indicated that the PDGF-positive cells were astrocytes. The increased PDGF immunoreactivity was associated with only minor changes in total PDGF mRNA and PDGF protein levels in the lesioned area. Reverse transcription-polymerase chain reaction (RT-PCR) demonstrated a slight increase in PDGF mRNA after ibotenic acid lesion, but this was not reflected in an increase in PDGF A-and B-chain protein concentration as measured with ELISA. After sham operation an increase in PDGF protein concentration was seen, while the number of PDGF-immunoreactive cells was unchanged. The accumulation of PDGF in the astrocytes might reflect the role of PDGF in a repair process in neurodegenerative processes.