Enhanced accumulation of injected inorganic mercury in renal outer medulla after unilateral nephrectomy

The effects of unilateral nephrectomy on renal accumulation and intrarenal distribution of mercury following a single injection of mercuric chloride (HgCl2, 0.5 mumol Hg/kg body wt, ip) were evaluated in the rat. In rats injected with HgCl2 immediately after nephrectomy or 10, 28, or 43 days after nephrectomy, the accumulation of mercury in the renal outer medulla was significantly greater than in respective sham-operated control rats. The increased accumulation of mercury in renal outer medulla was evident at 24 hr after injection of HgCl2 and persisted for at least 72 hr. The effect appeared to be a phenomenon associated specifically with the renal outer medulla in that elevated concentrations of mercury in the outer medulla were observed in the absence of similar elevations in the renal cortex, inner medulla, liver, and blood or in the whole body mercury content. Urinary excretion of mercury was unaffected by nephrectomy. Thus, associated with unilateral nephrectomy are changes in the renal accumulation and intrarenal distribution of systemically administered inorganic mercury that persist long after the rapid phase of compensatory renal growth (0-7 days) is completed.