Gene expression for alpha- and beta-isoforms of phosphatidylinositol transfer protein (PITP) was examined using in situ hybridization histochemistry in developing and mature rat brains. During embryonic and early post-natal stages, gene expression for both PITP-alpha and -beta were detected widely throughout the entire neuraxis. In the adult brain, the expression for PITP-alpha was positive in almost all neurons throughout the entire brain while the expression for PITP-beta markedly decreased in the entire gray matter regions except for the cerebellar cortex. By comparison with the previous findings on the expression for various molecules involved in the PI turnover, the present finding suggests that PITP is involved more intimately in some differentiation-related functions of immature neurons than those of mature neurons in co-operation with PI-related molecules and that PITPs exert their functions in adult brain in concert with PLCs in subtype-preferable inter-relation.