Recovery of erythrocyte Li+/Na+ countertransport and choline transport from lithium therapy.
Li+/Na+ countertransport, choline transport, and intracellular Li+ and choline were measured in the RBC of a manic-depressive subject as a function of time after termination of Li+ therapy. Countertransport recovered from its inhibition by Li+ in 10 days. This recovery involved a decrease in the Michaelis-Menten parameter Km, without change in Vmax. RBC choline decreased, and choline influx rose, much more slowly back towards pre-Li+ values over the course of two months. Thus, choline transport was still inhibited long after Li+ levels in RBC and plasma had become undetectable. Measurements on age-separated RBC fractions showed that recovery of choline transport was mainly in the young-cell fraction. Hence inhibition of choline transport by Li+ may be irreversible at the level of the individual RBC.
D001714:Bipolar Disorder / Q000097:blood / Q000188:drug therapy*; D002794:Choline / Q000097:blood*; D004912:Erythrocytes / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008094:Lithium / Q000097:blood / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012964:Sodium / Q000097:blood*
D008094:Lithium; D012964:Sodium; D002794:Choline