Effect of calcium channel blockers on vertebral bone marrow perfusion of the lumbar spine.
OBJECTIVE
To investigate the effect of calcium channel blockers on blood perfusion of vertebral bone marrow in the lumbar spine.


METHODS
Sixteen healthy volunteers (eight men and eight women) underwent dynamic contrast material-enhanced magnetic resonance (MR) imaging of the lumbar spine. One hundred twenty minutes after the first MR examination, each subject ingested 10 mg sublingual nifedipine before undergoing a second MR examination 20-25 minutes later. Semiquantitative (peak enhancement ratio and enhancement slope) and quantitative (amplitude and rate constant of the exchange [K(out)]) parameters were analyzed with the time-intensity curve. Data obtained before and after administration of nifedipine were compared. The Wilcoxon signed rank test and Spearman rank correlation test were used.


RESULTS
Median peak enhancement ratio of vertebral bodies decreased from 0.60 (mean +/- SD, 0.68 +/- 0.29) to 0.51 (mean, 0.56 +/- 0.24) after administration of nifedipine. Median and mean decreases were 0.11 and 0.12 +/- 0.15, respectively, and the percentage difference was 17% (P =.005). A P value of less than.05 was considered to indicate a statistically significant difference. Median enhancement slope changed from 0.45 (mean, 0.45 +/- 0.13) to 0.41 (mean, 0.40 +/- 0.24). Median and mean changes were 0.05 and 0.04 +/- 0.23, respectively, and the percentage difference was 9% (P =.334). Median amplitude changed from 0.059 (mean, 0.059 +/- 0.028) to 0.045 (mean, 0.048 +/- 0.023). Median and mean changes were 0.008 and 0.011 +/- 0.025, respectively, and the percentage difference was 18% (P =.072). Median K(out) changed from 0.068 (mean, 0.063 +/- 0.018) to 0.067 (mean, 0.066 +/- 0.028). Median and mean changes were 0.011 and 0.004 +/- 0.028, respectively (P =.404). Nifedipine affected peak enhancement ratio significantly but did not affect enhancement slope, amplitude, or K(out). Data before and after administration of nifedipine showed no differences between men and women. Spearman rank correlation coefficients suggest no significance between the differences in heart rate and blood pressure and the differences in peak enhancement ratio, enhancement slope, amplitude, or K(out).


CONCLUSIONS
After sublingual administration of nifedipine, the peak enhancement ratio of vertebral bone marrow decreased.
Shih
Tiffany Ting-Fang
TT
Department of Radiology and Internal Medicine, National Taiwan University, Medical College and Hospital, 7 Chung-Shan S Rd, Taipei 100, Taiwan. ttfshih@ha.mc.ntu.edu.tw
Chang
Chee-Jen
CJ
Tseng
Wen-Yih Isaac
WY
Hsiao
Jong-Kai
JK
Shen
Ling-Chun
LC
Liu
Tsang-Wu
TW
Yang
Pan-Chyr
PC
D000328:Adult; D001794:Blood Pressure / Q000187:drug effects; D001853:Bone Marrow / Q000000981:diagnostic imaging / Q000187:drug effects*; D002121:Calcium Channel Blockers / Q000008:administration & dosage*; D003971:Diastole / Q000187:drug effects; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging / Q000187:drug effects; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009543:Nifedipine / Q000008:administration & dosage; D010477:Perfusion; D011856:Radiographic Image Enhancement; D012016:Reference Values; D012737:Sex Factors; D018709:Statistics, Nonparametric; D013599:Systole / Q000187:drug effects
D002121:Calcium Channel Blockers; D009543:Nifedipine