HIV-1 GP120 PRODUCES DNA FRAGMENTATION IN THE CEREBRAL-CORTEX OF RAT

In the present experiments we have used morphological techniques to st udy the neuropathological pro file of the brain of rats after intracer ebroventricular (i.c.v.) injection of recombinant HIV-1 gp 120. Using brain cryostat sections (10 mu m) from rats treated with a single, dai ly dose of gp120 (100 ng/rat) given for 7 and 14 consecutive days, in situ DNA fragmentation was revealed in the neocortex but not in the hi ppocampus by terminal deoxylnucleotidyl transferase (TdT)-mediated dUT P-biotin nick end-labelling (TUNEL). In these rats, dark degenerating neurones were observed in the neocortex but not in the hippocampus. Tr eatment with bovine serum albumin (300 ng/rat i.c.v.) for up to 14 day s did not produce DNA fragmentation nor did it yield neuropathological lesions of the neocortex or hippocampus. In conclusion the present da ta demonstrate that gp 120 given i.c.v. produced DNA fragmentation in the neocortex, thus suggesting that apoptosis is the mechanism through which neurones ones of the neocortex are killed. (C) 1995 Academic Pr ess, Inc.