In reply

Abstract

We thank Drs Keven and Ekmekçi for their comments on our article. Adenosine, similar to other factors, such as nitric oxide1Welch W.J. Wilcox C.S. Thomson S.C. Nitric oxide and tubuloglomerular feedback.Semin Nephrol. 1999; 19: 251-262PubMed Google Scholar or thromboxane,2Welch W.J. Wilcox C.S. Potentiation of tubuloglomerular feedback in the rat by thromboxane mimetic Role of macula densa.J Clin Invest. 1992; 89: 1857-1865Crossref PubMed Scopus (76) Google Scholar seems to have a role in the physiology of the tubuloglomerular feedback mechanism. However, because angiotensin-converting enzyme inhibitors and angiotensin II blockers do not influence adenosine levels, any potentially protective effect from these agents could not be explained through this mechanism. One could argue that they counteract the vasoconstriction of adenosine, but direct modulation of renin release probably is much more effective. However, we believe it would be too early to postulate a true protective effect of angiotensin-converting enzyme inhibitors or angiotensin II blockers on posttransplantation kidney function. Our results rather should be interpreted as evidence for the safety of the administration of these drugs immediately after transplantation. ALL LETTERS TO THE EDITOR MUST BE SUBMITTED ONLINE VIA EDITORIAL MAN-AGER (http://ajkd.edmgr.com). Letters should be in response to an AJKD article, and that article should have appeared no more than 6 months previously. The title must be different from that of the original article. Letters must not exceed 250 words (excluding references, maxi-mum number 10) and contain no more than 1 figure or table. Letters are subject to editing and abridgment without notice and there is no guarantee that your letter will be published. Submitting the letter constitutes your permission for its publication in any current or subse-quent issue or edition of AJKD, in any form or media, now known or hereafter developed. ALL LETTERS TO THE EDITOR MUST BE SUBMITTED ONLINE VIA EDITORIAL MAN-AGER (http://ajkd.edmgr.com). Letters should be in response to an AJKD article, and that article should have appeared no more than 6 months previously. The title must be different from that of the original article. Letters must not exceed 250 words (excluding references, maxi-mum number 10) and contain no more than 1 figure or table. Letters are subject to editing and abridgment without notice and there is no guarantee that your letter will be published. Submitting the letter constitutes your permission for its publication in any current or subse-quent issue or edition of AJKD, in any form or media, now known or hereafter developed. The effect of ACE inhibitor and angiotensin II blocker therapy on early posttransplant kidney graft functionAmerican Journal of Kidney DiseasesVol. 43Issue 6PreviewBackground: It is unknown whether continuation of angiotensin-converting enzyme (ACE) inhibitor or angiotensin II (ATII) blocker therapy after kidney transplantation has an influence on early kidney graft function. Methods: We compared early postoperative graft function between 260 cadaveric kidney transplant recipients, either with or without peritransplantation ACE inhibitor/ATII blocker therapy. Regression analysis was used to show the influence of variables interfering with posttransplantation serum creatinine levels. Full-Text PDF Opposing mechanisms in tubuloglomerular feedbackAmerican Journal of Kidney DiseasesVol. 44Issue 3PreviewWe read with interest the article by Lorenz et al1 reporting the beneficial effect of early angiotensin-converting enzyme (ACE) inhibitor and angiotensin II receptor blocker (ARB) therapy after transplantation. They found that ACE inhibitors and ARBs have induced faster recovery on allograft function, whereas delayed graft function was similar in treatment and control groups. The investigators state that decreased absorption of sodium and fluid due to severe injury of the proximal tubule causes more volume delivery to the distal tubule, which stimulates macula densa cells to release renin. Full-Text PDF