INTRACEREBRAL INJECTION OF HUMAN-IMMUNODEFICIENCY-VIRUS TYPE-1 COAT GLYCOPROTEIN GP120 DOES NOT PRODUCE NEURODEGENERATION IS RATS

The human immunodeficiency virus type 1 (HIV-1) coat glycoprotein, GP1 20 has been reported to cause death of several neuronal cell types mai ntained in vitro. In the present experiments the gross behavioural, el ectrocortical (ECoG) and neuropathological effects of GP120 were studi ed in rats chronically microinfused into one lateral cerebral ventricl e (i.c.v.) via mini-osmotic pumps. Treatment with GP120 (100 ng/day) f or 1, 7 and 14 consecutive days lacked postural, motor and ECoG effect s nor did it produce any apparent brain damage. In addition, acute i.c .v. injection of a subconvulsive dose (500 ng) of N-methyl-D-aspartate (NMDA) did not produce motor and ECoG epileptogenic discharges in rat s which received 1 h beforehand a dose of GP120 (900 ng) into the dors al hippocampus ipsilateral to the injected ventricle; per se this dose of GP120 was ineffective. In conclusion, the present experiments demo nstrate that acute or chronic microinfusion of GP120 into the rat cere bral ventricular system does not produce neurotoxic effects. In additi on, they demonstrate that intrahippocampal GP120 does not sensitize ra ts to the excitotoxic effects of a subconvulsive dose of NMDA.