抄録
In order to investigate distribution of PAL, PAL-P, PAM and PAM-P in the living body after oral administration of B_6 derivatives, the authors studied the adsorption and elution of four types of B_6 for Dowex 1×8 and Amberlite CG-120 and established the following fractional determination method. When the blood was deproteinized with trichloroacetic acid and the solution was charged on Dowex 1×8 column previously equilibrated at pH 4.0. PAL-P was selectively adsorbed. On the other hand, PAL, PAM and PAM-P were not adsorbed by the resin but passed through completely. Dowex effluent was adsorbed to Amberlite CG -120 (pH 4.0) . Then PAL, PAM and PAM-P were separated with 0.1_M phosphate buffer (pH 7.5), 0.4_M Na_2 HPO_4 solution and 0.4_M phosphate buffer (pH 7.5) respectively. PAM and PAM-P were transformed to PAL and PAL-P with Na-glyoxalate. PAL-P adsorbed to Dowex 1×8 was eluted with 0.1_M phosphate buffer (pH 7.5) containing M NaCl. PAL and PAL-P were determined as 4-pyridoxic acid lactone and pyridoxic acid-5' -phosphate, respectively. When 2 mμmol of four types of vitamin B_6 were added to 1 ml of milk and plasma the recoveries of PAL, PAM and PAM-P were 95 to 104%, by the above method, but that of PAL-P was consistently 90%. The sums of the four types of B_6 in blood after oral administration of various B_6 derivatives in rabbits were 80 to 120% of total amount of B_6 obtained by a biological assay using Sacch. carlsbergensis.
