LITHIUM TRANSPORT IN THE CHICKEN AND MARINE TELEOST KIDNEY

The clearance ratio-C-Li/C-In (Excretion Fraction of Lithium-EF(Li)) i n the cod (Gadus morrhua L.) kidney amounts to 15.1 +/- 4.7, in the bl ack sculpin (Myoxocephalus scorpius L.) kidney, to 6.88 +/- 1.22, whic h indicates secretion of lithium by the marine teleost kidney. A direc t correlation,nas been found between EF(Li) and EF(Mg). Injection of f urosemide (15 mg/kg B.W.) increases while injection of the 20% para-am ino-hippurate solution (1.6 ml/kg B.W.) does not change EF(Li) in the cod kidney. Infusion of 10 mM LiNO3 in the 0.9% NaCl solution (3.5 ml/ kg B.W.) into the chicken (Gallus domesticus L.) left v. saphena produ ces, owing to the lithium inflow into the renoportal system, a marked unilateral increase of the renal lithium excretion. Infusion of 10% Na Cl solution (3.5 ml/kg B.W.) together with 10 mM LiNO3 into the chicke n left v. saphena is accompanied by a more pronounced ipsilateral incr ease of the lithium excretion and EF(Li). The data obtained indicate d iversity of mechanisms (glomerular filtration, reabsorption and secret ion) participating in the renal lithium excretion in the animals studi ed.