To determine whether the pharmacokinetics and pharmacodynamics of beta-blockade differ among racial groups, we gave 10 men of Chinese descent and 10 American white men 10, 20, 40, and 80 mg of propranolol every eight hours; the dosages were given in random order, and each dose was given for one day. The degree of beta-blockade was measured as the reduction in the heart rate and blood pressure in the supine and upright positions and during treadmill exercise testing. The Chinese subjects had at least a twofold greater sensitivity to the beta-blocking effects of propranolol than the white subjects, as indicated by the mean (+/- SEM) plasma concentrations producing a 20 percent reduction in the heart rate in both the supine position (197 +/- 31 vs. 536 +/- 58 nmol per liter; P less than 0.05) and the upright position (131 +/- 27 vs. 343 +/- 39 nmol per liter; P less than 0.05) and after exercise testing (96 +/- 12 vs. 185 +/- 23 nmol per liter; P less than 0.05). In addition, the Chinese subjects had much greater sensitivity to the hypotensive effects of propranolol, as shown by the concentrations that reduced blood pressure by 10 percent in the supine position (73 +/- 5 vs. 748 +/- 7 nmol per liter; P less than 0.01) and in the upright position (89 +/- 5 vs. 401 +/- 6 nmol per liter; P less than 0.01). No difference in beta-receptor density or affinity of lymphocytes was found between the groups. The Chinese group had a 45 percent higher free fraction of propranolol in plasma, which may have contributed to the increased drug effect but cannot explain it entirely. This group metabolized propranolol more rapidly than the white group, which resulted in a 76 percent higher clearance of an oral dose (3740 +/- 737 vs. 2125 +/- 214 ml per minute; P less than 0.05) because of increased metabolism through multiple metabolic pathways. We conclude that Chinese men have greater sensitivity than white men to the effects of propranolol on heart rate and blood pressure. Decreased protein binding may be responsible in part, but most of the effect remains to be explained.
Source Information
Division of Clinical Pharmacology, Vanderbilt University, Nashville, TN 37232.
This article has been cited by other articles:
Kim, K., Johnson, J. A., Derendorf, H.
(2004). Differences in Drug Pharmacokinetics Between East Asians and Caucasians and the Role of Genetic Polymorphisms. J Clin Pharmacol
44: 1083-1105
[Abstract][Full Text]
Bjornsson, T. D., Wagner, J. A., Donahue, S. R., Harper, D., Karim, A., Khouri, M. S., Murphy, W. R., Roman, K., Schneck, D., Sonnichsen, D. S., Stalker, D. J., Wise, S. D., Dombey, S., Loew, C.
(2003). A Review and Assessment of Potential Sources of Ethnic Differences in Drug Responsiveness. J Clin Pharmacol
43: 943-967
[Abstract][Full Text]
Chong, A.-Y., Rajaratnam, R., Hussein, N.-R., Lip, G. Y.H.
(2003). Heart failure in a multiethnic population in Kuala Lumpur, Malaysia. Eur J Heart Fail
5: 569-574
[Abstract][Full Text]
Cheng, C., Wong, W.-m., Lai, K.-c., Chun-yu Wong, B., HC Hu, W., Hui, W.-m., Lam, S.-k.
(2003). Psychosocial Factors in Patients With Noncardiac Chest Pain. Psychosom. Med.
65: 443-449
[Abstract][Full Text]
Evans, W E
(2003). Pharmacogenomics: marshalling the human genome to individualise drug therapy. Gut
52: ii10-18
[Abstract][Full Text]
Benowitz, N. L.
(2002). Smoking Cessation Trials Targeted to Racial and Economic Minority Groups. JAMA
288: 497-499
[Full Text]
Roden, D. M., Brown, N. J.
(2001). Preprescription Genotyping : Not Yet Ready for Prime Time, but Getting There. Circulation
103: 1608-1610
[Full Text]
Williams, D. G., Hatch, D. J., Howard, R. F.
(2001). Codeine phosphate in paediatric medicine. Br J Anaesth
86: 413-421
[Abstract][Full Text]
Collins, L. M., Bevan, J. C., Bevan, D. R., Villar, G. C. P., Kahwaji, R., Smith, M. F., Donati, F.
(2000). The Prolonged Duration of Rocuronium in Chinese Patients. Anesth. Analg.
91: 1526-1530
[Abstract][Full Text]
Evans, W. E., Relling, M. V.
(1999). Pharmacogenomics: Translating Functional Genomics into Rational Therapeutics. Science
286: 487-491
[Abstract][Full Text]
Dallegri, F., Dapino, P., Arduino, N., Bertolotto, M., Ottonello, L.
(1999). Cefoperazone Prevents the Inactivation of alpha 1-Antitrypsin by Activated Neutrophils. Antimicrob. Agents Chemother.
43: 2307-2310
[Abstract][Full Text]
Darbar, D., Fromm, M. F., Dell'Orto, S., Kim, R. B., Kroemer, H. K., Eichelbaum, M., Roden, D. M.
(1998). Modulation by Dietary Salt of Verapamil Disposition in Humans. Circulation
98: 2702-2708
[Abstract][Full Text]
Hui, K. K., Pasic, J.
(1997). Outcome of Hypertension Management in Asian Americans. Arch Intern Med
157: 1345-1348
[Abstract]
Lin, K.-M., Poland, R. E., Anderson, D.
(1995). Psychopharmacology, Ethnicity and Culture. Transcultural Psychiatry
32: 3-40
Mills, P. J., Dimsdale, J. E., Ziegler, M. G., Nelesen, R. A.
(1995). Racial Differences in Epinephrine and ß2-Adrenergic Receptors. Hypertension
25: 88-91
[Abstract][Full Text]
Carter, B. L., Frohlich, E. D., Elliott, W. J., Moore, M. A., Mann, R. J., Roberts, R. W.
(1994). Selected Factors That Influence Responses to Antihypertensives: Choosing Therapy for the Uncomplicated Patient. Arch Fam Med
3: 528-535
[Abstract]
Lam, Y.W. F., Marshall, M. V.
(1992). Genetically Determined Polymorphisms in Drug Metabolism. Journal of Pharmacy Practice
5: 317-336
[Abstract]
Caporaso, N. E., Shaw, G. L.
(1991). Clinical Implications of the Competitive Inhibition of the Debrisoquin-Metabolizing Isozyme by Quinidine. Arch Intern Med
151: 1985-1992
[Abstract]
Anastos, K., Charney, P., Charon, R. A., Cohen, E., Jones, C. Y., Marte, C., Swiderski, D. M., Wheat, M. E., Williams, S.
(1991). Hypertension in Women: What is Really Known? The Women's Caucus, Working Group on Women's Health of the Society of General Internal Medicine. ANN INTERN MED
115: 287-293
[Abstract]
(1990). Therapeutic Substitution and Formulary Systems. ANN INTERN MED
113: 160-163
[Abstract]