Effect of chlorpromazine on the cytoplasmic phosphatidate phosphohydrolase in rat liver.
The inhibitory effect of chlorpromazine on phosphatidate phosphohydrolase (EC 3.1.3.4) activity was studied with respect to the selectivity of the molecular species of phosphatidate. Rat liver microsomes which include endogenously labeled [(14)C]phosphatidic acid were prepared by the incubation of microsomes with sn-[(14)C]glycerol-3-phosphate and used as substrate. The distribution of radioactivity among the molecular species of [(14)C]phosphatidate remaining after incomplete hydrolysis of the substrate exhibited little difference from that of the untreated substrate. When the hydrolysis was suppressed by the addition of chlorpromazine, however, the radioactivity distributed in the monoenoic and dienoic [(14)C]phosphatidate increased. The preference of the molecular species of phosphatidate in the inhibition was further confirmed by the experiment run with microsomes containing 2-[1-(14)C]palmitoyl, oleoyl, linoleoyl and arachidonyl species of phosphatidate as substrate.
Ide
H
H
Medical Research Institute, Tokyo Medical and Dental University, 3-10, 2-chome, Kanda-Surugadai, Chiyoda-ku, Tokyo 101, Japan.
Nakazawa
Y
Y
D000818:Animals; D002746:Chlorpromazine / Q000494:pharmacology*; D003593:Cytoplasm / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008297:Male; D008862:Microsomes, Liver / Q000378:metabolism; D010711:Phosphatidate Phosphatase / Q000378:metabolism*; D010712:Phosphatidic Acids / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013347:Subcellular Fractions / Q000378:metabolism; D013379:Substrate Specificity
D010712:Phosphatidic Acids; D010711:Phosphatidate Phosphatase; D002746:Chlorpromazine