Lithium administration and phosphate excretion

Publisher Website
Google Scholar
Abstract
The phosphaturic effect of parathyroid hormone (PTH), cyclic[c]AMP, acetazolamide (Az) and HCO3 loading was studied in normal, thyroparathyroidectomized (TPTX) and Li-treated dogs. PTH administration to normal animals markedly increased fractional excretion (F) of PO4 but had a blunted effect on FPO4 in the Li-treated animals. Amp likewise markedly increased FPO4 in the normal animals but had a markedly blunted effect in the Li-treated animals. Az led to a significant increase in FNa, FHCO3, and FPO4 in the normal animals. In the Li-treated dogs, Az induced a significant natriuresis and bicarbonaturia but failed to increase phosphaturia. HCO3 loading in normal dogs caused a significant phosphaturia while having little effect on FPO4 in Li-treated dogs. HCO3 loading to TPTX dogs was associated with a lower FPO4 as compared to normal HCO3-loaded animals. Li administration may not only block the adenyl cyclase-cAMP system in the renal cortex, but it may also interfere with a step distal to the formation of cAMP, since the phosphaturic effect of both PTH and cAMP was markedly diminished in Li-treated animals. Complications of the psychotherapeutic use of Li salts are discussed.].