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 intrastri atal ibotenic acid injections. The most pronounced effect registered w as that the number of PDGF-immunoreactive cells increased in the lesio ned area up to 10 weeks after the surgery. Double immunofluorescence s taining indicated that the PDGF-positive cells were astrocytes. The in creased PDGF immunoreactivity was associated with only minor changes i n total PDGF mRNA and PDGF protein levels in the lesioned area. Revers e transcription-polymerase chain reaction (RT-PCR) demonstrated a slig ht increase in PDGF mRNA after ibotenic acid lesion, but this was not reflected in an increase in PDGF A-and B-chain protein concentration a s measured with ELISA. After sham operation an increase in PDGF protei n concentration was seen, while the number of PDGF-immunoreactive cell s was unchanged. The accumulation of PDGF in the astrocytes might refl ect the role of PDGF in a repair process in neurodegenerative processe s.