Potassium carbonate

Specific investigations: other studies

Administrative data

Endpoint:

biochemical or cellular interactions

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well documented publication report which meets basic scientific principles

Data source

Reference

Reference Type:

publication

Title:

Participation of urinary Na+, K+, pH, and L-ascorbic acid in the proliferative response of the bladder epithelium after the oral administration of various salts and/or ascorbic acid to rats

Author:

Shibata M-A, Tamano S, Kurata Y, Hagiwara A, Fukushima S

Year:

1989

Bibliographic source:

Food Chem. Toxic. 27(6): 403-413

Materials and methods

GLP compliance:

not specified

Type of method:

in vivo

Test material

Test material information

Constituent 1

Reference substance name:

Potassium carbonate

EC Number:

209-529-3

EC Name:

Potassium carbonate

Cas Number:

584-08-7

Molecular formula:

CH2O3.2K

IUPAC Name:

dipotassium carbonate

Test animals

Species:

rat

Strain:

Fischer 344

Sex:

male

Details on test animals or test system and environmental conditions:

They were housed in plastic cages on hard-wood chip bedding in an environmentally controlled room, maintained at 22 +/- 2 °C and artificially illuminated for 12 hours each day.

Administration / exposure

Route of administration:

oral: feed

Vehicle:

other: powdered basal diet

Details on exposure:

Powdered basal diet (Oriental M, Oriental Yeast Co, Tokyo, japan) suppemented with 3 % Potassium carbonate.

Applicant's summary and conclusion

Conclusions:

Changes in urinary parameters (electrolyte levels and pH) and DNA synthesis and the morphology of the bladder epithelium were investigated in male rats that were fed for 4 or 8 weeks on diets containing various 
Na, K, Mg or Ca carbonate salts (3 %) with or without L-ascorbic acid (5 %). Beside increases in urinary pH, sodium and potassium and decreases of chloride, DNA synthesis in the bladder epithelium was increased in groups given sodium bicarbonate, potassium carbonate with or without L-ascorbic acid. 
Furthermore some morphological alterations in the bladder epithelium were detected by light microscopy hyperplasia consisting of diffuse thickening of the epithelium with four to eight  layers of the epithelial cells addjected) and scanning electron microscopy (pleomorphic or short, uniform microvilli and ropy or leafy microridges). Administration of ascorbic acid in combination with the salts induced levels of change greater than those with the salts alone. 
After administration of ascorbic acid or NH4C alone, resulting in a drop of urinary pH, those effects on the bladder epithelium were not observed. 
Therefore, the study authors suggest that the degree of DNA synthesis and/or morphological alteration in the rat-bladder epithelium after treatment with various bases may depend on changes in urinary concentrations of Na- or K-ions and/or pH, and the presence of ascorbic acid in the urine.