Influence of Secondary Hyperparathyroidism Induced by Low Dietary Calcium, Vitamin D Deficiency, and Renal Failure on Circulating Rat PTH Molecular Forms

Table 2

Evolution of rPTH and rPTH ratio with various diets and partial nephrectomy.

Parameters	Normal calcium (0.5%)	Low calcium (0.1%)	Vitamin D deficiency	Moderate renal failure	Severe renal failure
N	10	12	13	7	7
W-rTH (pmol/L)	4.0±1.2	7.7±3.9^∗	15.0±7.6^∗∗∗,++	11.6±4.9^∗∗∗	114±72.6^***,••
T-rPTH (pmol/L)	5.9±1.4	11.1±5.1	20.8±9.9^∗∗∗,++	13.4±6.9	116.1 ± 79.1^***,•
C-rPTH (pmol/L)	7.3±2.6	17.4±8.9^∗∗∗	37.2±15.8^∗∗∗,+++	23.1±15.0^∗∗∗	268.4±121.4^∗∗∗,••
T/W-rPTH ratio	1.50±0.13	1.48±0.12	1.41±0.10	1.12±0.38^∗	0.97±0.13^∗∗∗
C/W-rPTH ratio	1.85±0.46	2.35±0.47	2.66±0.70	2.02±0.84	2.73±1.51
C/T-rPTH ratio	1.24±0.35	1.58±0.29	1.88±0.49^∗	2.24±1.65	2.96±2.07^∗∗∗

Results are means + SD. All group statistics were assessed by ANOVA, followed by Dunnett’s multiple comparison test (Kruskal-Wallis ANOVA followed by Dunn’s comparison test for rTotal-PTH, rTotal/rWhole ratio, rCarboxyl/rTotal ratio) *𝑃<.05; **𝑃<.01; ***𝑃<.001. Unpaired T-test with or without Welch correction: low-calcium versus vitamin D-deficient diet: ⁺𝑃<.05; ⁺⁺𝑃<.01; ⁺⁺⁺𝑃<.001. Moderate versus severe renal failure: ^•𝑃<.05; ^••𝑃<.01; ^•••𝑃<.001.