Figure 5.

Relative efficacy of ZJ43 and (R,S)-2-phosphono-methylpentanedioic acid (2-PMPA) in inhibition of N-acetylaspartylglutamate (NAAG) peptidase activity in vivo. (a) Saline or the peptidase inhibitors were injected (intraperitoneally (i.p.)) 30 min before injection of [³H]-NAAG into the lateral ventricle. Relative peptidase inhibition is estimated as a percent of [³H]-glutamate released from [³H]-NAAG over 30 min following [³H]-NAAG injection. [³H]-NAAG hydrolysis (enzyme activity) is expressed relative to the saline treatment group as 100%. Control group n=27; other treatment groups n=7–12. (b) [³H]-NAAG was injected at different intervals after i.p. injection of ZJ43 at 150 mg kg⁻¹ (i.p.) and hydrolysis was followed over 30 min intervals as in a. All values are means±s.e.m. Saline group n=20; treatment groups n=8–12.