Evaluation of the Phototoxic Potential of the Diuretic Agents by the Photohemolysis Test and the Candida albicans Test

Lee, Ho Seong; Kim, Tae Heung; Park, Ki Beom; Park, Cheol Keun

Abstract

BACKGROUND: Diuretic agents are widely used in the treatment of variable diseases. Although some diuretics may cause photosensitive reactions, this has been a relatively neglwted area of investigation.
OBJECTIVE
The study was undertaken to examine whether or not the diuretic agents could cause phototoxicity with the photohemolysis test and with the Candida albica as test. METHOD: Photohemolysis test: Fresh human red blood cells (RHC) were washed and diluted to 200 fold of original volume with TCM buffer. Test compound suspension, were added to the diluted blood at the final concentration of 10 M. Each sample was irradiated with 50 J/cm of UVA, and control samples were incubated in water bath with light shielding. After additional incubation in a dark water bath for 30 minutes the sarnples were centrifuged. After adding Drabkins reagent, measurement of absorbance of the supernatents by speetrophotometer at 420, 540, 550nm were performed. The degree of photohemolysis was determined by comparing the results wiith the control solution. Candide elbicens test wenty microliter of each solution of arious diuretics were applied to Sabourauds dextrose agar plate in which Candida albicanp had been diffusely applied previously. Four hours after the application, 80 J/cm of UVA was irradiated. The irraicated plates and nonirradiated controls were incubated in a darlI room for 48 hours, and were examined clearzones arround the drugs as the mean of positive results fcir the phototoxic potential of the drugs.
RESULTS
The photohemolyeii; vaIues of azosemide, spironolaetonet, iamterene, and xipamide at 420, 540, and 550nm were 70.57%/28.36%/31.61%/83.65%/16.40%/15.21%/75.66%/25.40%/28.17%, and 14.02%/9.11%/8.99% respectively, which exceeds the mear,injful positive value of above 5 , With the Candida olbicans test all teat solution at concentration of 1% and 5% showed negstive results.
CONCLUSION
A phototoxic reaction may be triggered by azosemide, spironolactone, triamterene, and xipamide, and the possible mechanism concerned may be directed to cellular membranes. However with the negative result of knowed photosensitizers like hydrochlorthiazid and furosemide, there may be other possibilities for the explenation of phototoxicity. Thus further stirdies may be necessary to investigate more details about the cliscrepancies in greates detail.