Netopilova M, Drsata J, Ulrichová J
Department of Biochemical Sciences, Faculty of Pharmacy, Charley University, Kradec Králové, Czech Republic.
Pharmazie. 1996 Aug;51(8):589-91.
The inhibitory activity of the quaternary benzophenanthridine alkaloid sanguinarine on rat brain glutamate decarboxylase (GAD; EC 4.1.1.15) was studied in vitro. A value of Ki 7.10(-4) mol.1(-1) for sanguinarine was found. The inhibition was irreversible and increased during the preincubation time of sanguinarine with the GAD preparation. The results suggest that reaction of the iminium bond in the benzophenanthridine molecule with thiol groups of the enzyme participates in GAD inhibition. As GAD catalyzes the rate-limiting step of GABA synthesis, its inhibition by sanguinarine may contribute to its physiological action in vivo.
在体外研究了季铵型苯并菲啶生物碱血根碱对大鼠脑谷氨酸脱羧酶（GAD；EC 4.1.1.15）的抑制活性。发现血根碱的Ki值为7.1×10⁻⁴ mol·L⁻¹。这种抑制是不可逆的，并且在血根碱与GAD制剂预孵育期间会增强。结果表明，苯并菲啶分子中的亚胺键与该酶的巯基反应参与了对GAD的抑制作用。由于GAD催化γ-氨基丁酸（GABA）合成的限速步骤，血根碱对其的抑制作用可能有助于其在体内的生理作用。
