Safety of oral sulfates in rats and dogs contrasted with phosphate-induced nephropathy in rats.
An oral sulfate salt solution (OSS), under development as a bowel cleansing agent for colonoscopy in humans, is studied in rats and dogs. In rats, amaximumpractical oral OSS dose (5 g/kg/d) is compared with an oral sodium phosphate (OSP) solution, both at about 7 times the clinical dose. OSS induces the intended effects of loose stools and diarrhea. In rats, higher urine sodium and potassium accompany higher clearance rates, considered adaptive to the osmotic load of OSS. OSS for 28 days is well tolerated in rats and dogs. In contrast, OSP causes increased mortality, reduced body weight and food consumption, severe kidney tubular degeneration, and calcium phosphate deposition in rats. These are accompanied by mineralization in the stomach and aorta, along with cardiac and hepatic degeneration and necrosis. The greater safety margin of OSS over OSP at similarmultiples of the clinical dose indicates its suitability for human use.
Pelham
Russell W
RW
Braintree Laboratories Inc, 60 Columbian Street West, Braintree, MA 02185, USA. RPelham@braintreelabs.com
Russell
Robert G
RG
Padgett
Eric L
EL
Reno
Frederick E
FE
Cleveland
Mark vB
Mv
D000284:Administration, Oral; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002118:Calcium / Q000097:blood; D003113:Colonoscopy; D003404:Creatinine / Q000378:metabolism; D004285:Dogs; D005260:Female; D007668:Kidney / Q000187:drug effects* / Q000473:pathology; D008297:Male; D010710:Phosphates / Q000633:toxicity*; D011188:Potassium / Q000652:urine; D051381:Rats; D012964:Sodium / Q000097:blood / Q000652:urine; D013431:Sulfates / Q000633:toxicity*
D010710:Phosphates; D013431:Sulfates; D012964:Sodium; D003404:Creatinine; D011188:Potassium; C018279:sodium phosphate; D002118:Calcium