Renal metallothionein metabolism after a reduction of renal mass. I. Effect of unilateral nephrectomy and compensatory renal growth on basal and metal-induced renal metallothionein metabolism.
The effects of unilateral nephrectomy and compensatory renal growth on renal metallothionein metabolism were evaluated in the present study. In rats, the renal content of metallothionein increased in proportion to the increase in renal mass after unilateral nephrectomy and compensatory renal growth. However, when zinc was used to induce the synthesis of renal metallothionein, the remnant kidney in uninephrectomized (NPX) rats produced significantly greater amounts of metallothionein on a per gram kidney basis than a normal kidney in sham-operated (SO) rats. In both NPX and SO rats, zinc pretreatment caused metallothionein synthesis to increase primarily in the renal cortex and renal outer stripe of the outer medulla. Zinc pretreatment also changed the pattern for the intrarenal accumulation of inorganic mercury in NPX rats. After pretreatment with zinc, the accumulation of inorganic mercury predominated in the renal cortex rather than in the outer stripe of the outer medulla in the NPX rats. In addition, both NPX and SO rats were afforded complete protection against the nephrotoxic effects of a low, toxic dose of inorganic mercury when they were pretreated with inorganic zinc. The protection is postulated to be related to the alteration in the pattern of renal accumulation of inorganic mercury. In conclusion, the capacity to synthesize metallothionein increases significantly in rats after they have undergone unilateral nephrectomy and compensatory renal growth. The increased capacity of the remnant kidney to synthesize metallothionein may involve adaptive changes both in transcriptional and/or translational controls of metallothionein synthesis.
Zalups
R K
RK
Division of Basic Medical Sciences, Mercer University School of Medicine, Macon, GA 31207.
Cherian
M G
MG
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D007668:Kidney / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008627:Mercuric Chloride / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D008668:Metallothionein / Q000096:biosynthesis / Q000378:metabolism*; D009392:Nephrectomy; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D015032:Zinc / Q000378:metabolism / Q000494:pharmacology
D008627:Mercuric Chloride; D008668:Metallothionein; D015032:Zinc