Effect of the intracerebroventricular and systemic administration of L-serine on the concentrations of D- and L-serine in several brain areas and periphery of rat.
To gain further insight into the metabolic mechanism of endogenous D-serine, the effect of the intracerebroventricular and intraperitoneal administration of L-serine on the concentrations of D- and L-serine in several brain areas and periphery was investigated. The intracerebroventricular injection of L-serine caused a rapid and marked increase in the L-serine levels in almost all brain regions of adult rats. This administration also produced a gradual increase in the D-serine levels in the forebrain, whereas a slight but significant elevation of D-serine was found in the cerebellum and pons-medulla. The intraperitoneal administration of L-serine caused a marked increase in the L-serine levels in all brain regions of both infant and adult rats. The treatment induced a significant augmentation of the D-serine levels in all brain regions of infant rats with higher concentrations in the cerebellum and cortex, whereas no significant change was observed in the cerebellum and pons-medulla of adult rats. These in vivo observation, together with the fact that immunohistochemical studies have indicated that both D-serine and serine racemase are highly concentrated in Bergmann glia of developing cerebellum, suggest that D-serine can be synthesized not only in the forebrain but also in the hindbrain by serine racemase. Furthermore, because the drastic decline in the cerebellar D-serine level coincides well with a dramatic increase in the cerebellar D-amino acid oxidase during early postnatal development, synthesized D-serine may be metabolized by D-amino acid oxidase in the hindbrain of adult rats.
Hashimoto
Atsushi
A
Department of Pharmacology, School of Medicine, Tokai University, Isehara, Kanagawa 259-1193, Japan. hashimot@is.icc.u-tokai.ac.jp
D000375:Aging / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000187:drug effects* / Q000378:metabolism*; D007276:Injections, Intraventricular; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012694:Serine / Q000008:administration & dosage* / Q000096:biosynthesis / Q000378:metabolism*; D013237:Stereoisomerism
D012694:Serine