We thank Fukuda and Kimura for their comments on our article. While we concur with them that a reduction in glomerular pressure may be renoprotective, we do not a priori accept the statement that diuretics work that way. In this regard, several arguments need to be considered.
First, many other mechanisms, including, for instance, stimulation of the renin-angiotensin-aldosterone system, are involved in attaining a new steady state of sodium balance, when sodium intake is reduced by dietary manipulation or when sodium output is enhanced by a diuretic. The adaptation to diuretic treatment occurs swiftly and may precede any fall in blood pressure. In other words, it is not absolutely necessary to lower GFR to achieve a new steady state of sodium balance.
de Leeuw PW, Ruilope LM, INSIGHT Investigators. Can Calcium Channel Blockers Preserve Renal Function Better Than Diuretics During Antihypertensive Treatment?—Reply. Arch Intern Med. 2005;165(11):1312–1313. doi:10.1001/archinte.165.11.1312-b