Effect of aluminium on calcium-sensing receptor expression, proliferation, and apoptosis of parathyroid glands from rats with chronic renal failure.
BACKGROUND
To assess the effect of aluminium on the calcium-sensing receptor expression, proliferation, and apoptosis in parathyroid glands from rats with chronic renal failure, 2(1/2)-month-old male Wistar rats were 7/8 nephrectomized.


METHODS
Eight weeks after surgery the rats were divided into two groups, one receiving intraperitoneal AlCl3 for 8 weeks and the other receiving intraperitoneal placebo. Serum Al, Ca, P, creatinine, and PTH were measured. Parathyroid glands were removed, formaldehyde-fixed, and paraffin-embedded. Calcium-sensing receptor and proliferation were detected by immunohistochemistry and apoptosis by TUNEL and propidium iodide uptake.


RESULTS
At the end of the study, despite higher levels of serum P in the aluminium group (6.27 +/- 0.63 vs. 5.56 +/- 0.58 mg/dL; P = 0.045), serum PTH was lower (89.6 +/- 57.7 vs. 183.1 +/- 123.8 pg/mL; P = 0.059). No significant differences were found in the calcium-sensing receptor expression between groups (aluminium: 27.1 +/- 7.6; placebo: 25.4 +/- 3.5 RU). Rats receiving aluminium showed a significantly lower cell proliferation rate than the control rats (0.54 +/- 0.69 vs. 4.43 +/- 3.10 cells/mm2; P = 0.003). No apoptotic events were detected.


CONCLUSIONS
Aluminium was able to reduce the cell proliferation of the parathyroid glands. Due to the low apoptosis rate, however, it was not possible to find any change. Aluminium had no effect on the calcium-sensing receptor expression.
González-Suárez
Ignacio
I
Bone and Mineral Research Unit, Instituto Reina Sofía de Investigación, Hospital Central de Asturias, Oviedo, Spain.
Naves
Manuel
M
Díaz-Corte
Carmen
C
Fernández-Martín
José L
JL
Menéndez-Rodríguez
Primitiva
P
Cannata-Andía
Jorge B
JB
D000535:Aluminum / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry; D007676:Kidney Failure, Chronic / Q000150:complications / Q000378:metabolism*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D010280:Parathyroid Glands / Q000378:metabolism* / Q000473:pathology*; D010281:Parathyroid Hormone / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D044169:Receptors, Calcium-Sensing / Q000096:biosynthesis*; D014508:Urea / Q000378:metabolism
D010281:Parathyroid Hormone; D044169:Receptors, Calcium-Sensing; D014508:Urea; D000535:Aluminum