Reduced brain γ-amino-butyric acid (GABA) participates in the pathogenesis of schizophrenia. GABA scarcely penetrates the brain. We evaluated the pharmacological properties of BL-1020, a novel GABA ester of perphenazine. Oral BL-1020 or perphenazine were assessed in acute and subchronic schizophrenia rat models. Catalepsy, serum prolactin, receptor binding profile and cortical (PFC), hippocampal (Hip) and dopamine (DA) levels were determined. Radioactive [14C] labeled BL-1020 was used for pharmacokinetics (PK). Acute and subchronic treatment with BL-1020 antagonized amphetamine-induced hyperactivity, with significantly lower catalepsy and sedation compared to equimolar perphenazine. At the same time, BL-1020 increased DA release in the PFC and Hip. BL-1020 and perphenazine stimulated prolactin secretion equally. BL-1020 displayed strong DA and serotonin (5HT) receptor inhibition (D2L Kiz = 0.066 nM, D2S Ki = 0.062 nM, 5-HT2A Ki = 0.21 nM). PK data revealed that BL-1020 penetrated the brain. Conclusions: The advantages of BL-1020 for treatment of schizophrenia stem from its being a DA/5HT antagonist and a GABAergic agsonist that releases cortical DA and antagonizes amphetamine-induced hyperactivity with reduced catalepsy and sedation.
Bibliographical noteFunding Information:
The study was supported by grant provided by BiolineRX, and by the Chief Scientist of Israel.
We would like to acknowledge Shlomit Halachmi M.D., Ph.D. for her contribution to this study. The generous support for this work provided by the “Marcus Center for Pharmaceutical and Medicinal Chemistry” at Bar Ilan University, is gratefully acknowledged. Additional funding was provided by the Office of the Chief Scientist, Israel Ministry of Industry, Trade & Labor. We wish to thank Igor Tarasenko for his skilled technical contribution.