Skau M, Pakkenberg B, Buschard K, Bock T
Diabetes Research Laboratory, Bartholin Instituttet, H.S. Kommunehospitalet, Copenhagen, Denmark.
Diabetes. 2001 Aug;50(8):1763-70. doi: 10.2337/diabetes.50.8.1763.
To understand the dynamics of islet population, especially during conditions with growth of the total islet mass, it is important to have reliable estimators of parameters describing the quantitative appearance of the islet population. We describe a stereological estimator of the volume-weighted mean islet volume based on unbiased assumption-free stereological principles. The volume-weighted mean islet volume is the mean islet volume if the islets are weighted (sampled) proportional to their volume. This method allows simultaneously unbiased estimation of the total islet mass. With use of this method, 22 male Sprague-Dawley rats within the age span of 34-102 days old were investigated. We found a linear correlation (P < 0.001) between total islet mass and the volume-weighted mean islet volume. The results support models demonstrating that the physiological growth of the total islet mass in the period studied is totally or mainly caused by proportional growth of existing islets. The functional meaning of the volume-weighted mean islet volume is discussed, and previous methods to study the mean islet volume and islet number are critically evaluated. We propose the volume-weighted mean islet volume to be a biologically useful parameter when describing the mean volume of the pancreatic islets and investigating the differences between experimental groups.
为了解胰岛群体的动态变化，尤其是在胰岛总体积增加的情况下，拥有可靠的参数估计器来描述胰岛群体的定量特征非常重要。我们基于无偏倚、无假设的体视学原理，描述了一种体积加权平均胰岛体积的体视学估计器。体积加权平均胰岛体积是指如果胰岛按其体积比例加权（抽样）时的平均胰岛体积。该方法能够同时对胰岛总体积进行无偏估计。使用此方法，对22只年龄在34 - 102天的雄性Sprague-Dawley大鼠进行了研究。我们发现胰岛总体积与体积加权平均胰岛体积之间存在线性相关性（P < 0.001）。这些结果支持了一些模型，这些模型表明在所研究的时期内，胰岛总体积的生理增长完全或主要是由现有胰岛的比例性增长引起的。文中讨论了体积加权平均胰岛体积的功能意义，并对先前研究平均胰岛体积和胰岛数量的方法进行了批判性评估。我们建议，在描述胰岛平均体积和研究实验组之间的差异时，体积加权平均胰岛体积是一个具有生物学意义的有用参数。
