To elucidate the early effects of lithium treatment on the kidney, arginine-vasopressin (AVP) binding sites in the renal medulla were measured by radiolabeled receptor assay (RRA) in rats injected intra-peritoneally with lithium chloride (4 mmol/kg body weight) for 7 days. After the 8th day, urine volume of rats injected lithium (Li group ) increased and was significantly larger than that of the control rats that were injected physiological saline (control group). On the same day, the AVP binding capacities of renal medualla membranes of the Li group (Bmax = 28.9 ± 7.2 fmol/100 μg protein) were significantly lower than that of the control group ( Bmax = 50.0 ± 6.3 fmol/100 μg protein), but there was no difference in the dissociation constant between the two groups. Our findings suggested that lithium-induced diabetes insipidus was due to a reduction in the number of AVP binding sites in the kidney.
|Number of pages||8|
|Journal||Research Communications in Chemical Pathology and Pharmacology|
|Publication status||Published - 1985|
ASJC Scopus subject areas