The mechanism of polyuria in rats pretreated with lithium studies by in vitro microperfusion.

Abstract

The collecting ducts in papillae taken from normal rats have a measurable increase in diffusional tritiated water (THO) permeability with ADH 5 mu unit/ml and this increase is maximal with antidiuretic hormone (ADH) 100 mu unit/ml added to media. The presence of plasma from rats pretreated with lithium to make them polyuric inhibited the response to ADH. The lowest concentration of ADH that caused a measurable increase in diffusional water permeability was 50 mu unit/ml and the increase was maximal with ADH 2000 mu unit/ml. The maximum response to ADH did not differ whether plasma from control or lithium pretreated rats was used. However, the dose-response curve to ADH was shifted to the right by the plasma from lithium-pretreated rats. Lithium added to the plasma from control rats did not alter the response to ADH. It is proposed that lithium given to rats causes a circulatory factor to be produced that inhibits in a competitive fashion the response of the collecting duct to ADH. Such an effect would explain many features of the impairment of water excretion associated with lithium use.

• Authors: C Ray, T Morgan, S Carney
• Journal: Clinical and experimental pharmacology & physiology (Clin Exp Pharmacol Physiol) 1983 Mar-Apr Vol. 10 Issue 2 Pg. 153-60 ISSN: 0305-1870 [Print] Australia
• PMID: 6872333 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Vasopressins
• Lithium

Topics

• Animals
• Body Water (drug effects)
• Diabetes Insipidus (metabolism)
• Diuresis (drug effects)
• Kidney (drug effects)
• Lithium (pharmacology)
• Male
• Perfusion
• Permeability
• Rats
• Rats, Inbred Strains
• Vasopressins (pharmacology)