Estimation of total nephron number in Japanese subjects and the comparison with other races in relation to kidney and cardiovascular diseases

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K09631
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Kidney internal medicine
• Research Institution: Jikei University School of Medicine
• Principal Investigator: Tsuboi Nobuo 東京慈恵会医科大学, 医学部, 准教授 (40408422)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: ネフロン数 / CKD

Outline of Final Research Achievements

A total of 64 nephron kidneys were used to estimate the total number of nephrons. It was clarified that the total number of nephrons in the Japanese has a large individual difference even in the normal renal function, and is closely related to the function of the kidney. Furthermore, it was found that individuals with a history of hypertension had a lower number of nephrons than normotensive. It was revealed that the total number of nephrons in the Japanese population (600,000 / kidney) was lower as compared to the results of similar studies conducted in other races. This study was the first to be conducted for Asians, and its results were highly evaluated at domestic and overseas academic societies in the field of kidney disease and hypertension.

Free Research Field

腎臓内科学

Academic Significance and Societal Importance of the Research Achievements

総ネフロン数の差異は個人間の腎機能低下に対する感受性の違いのみならず、人種間でのCKDや末期腎不全の罹患率の違いにも影響することが予想される。既報の研究は、対象に多人種が混在しており、単一民族を対象とした検討は少ない。したがって、ほぼ単一民族とみなされる日本人を対象として総ネフロン数を計測する意義は大きい。
さらに、最近ではMRIを用いて腎の微細構造を解析し、総ネフロン数を非侵襲的に推定する試みもされている。このような新たな方法の確立においても、Stereologyを用いた総糸球体数の推算による検証は欠かせない。本研究結果はネフロン数研究における近未来的なアプローチを試みる上でも基礎となる。