Lithium transport across biological membranes.
Li+ is actively transported out of cells, and across different epithelia of both mammalian and amphibian origin. Due to the low affinity of the Na+/K(+)-ATPase for Li+, the transport is most likely energized by exchange and/or cotransport processes. The detailed mechanism by which Li+ is reabsorbed across the proximal tubule is not known, although it seems reasonable to assume that at least a part is by secondary active transcellular transport. The evidence further suggest that aldosterone and maybe vasopressin, through their effects on the Na+ channels in the late distal tubule and the collecting duct may be of significance in inducing distal Li+ reabsorption, as seen during severe sodium restriction in rats and dogs. Clearly more studies are needed to finally resolve these issues.
Holstein-Rathlou
N H
NH
Department of Physiology and Biophysics, University of Southern California School of Medicine, Los Angeles.
D000042:Absorption; D000818:Animals; D001692:Biological Transport / Q000502:physiology; D004848:Epithelium / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D007684:Kidney Tubules / Q000502:physiology; D008094:Lithium / Q000493:pharmacokinetics*; D010539:Permeability; D012867:Skin / Q000378:metabolism; D012964:Sodium / Q000378:metabolism
D008094:Lithium; D012964:Sodium