Abstract：
BACKGROUND: Porcine liver is widely used in hepatologic research as a large animal model with many anatomical and physiological similarities with humans. However, only limited information on porcine liver spatial microstructure has been published, especially regarding the hepatic sinusoids and bile canaliculi. The aim of our study was to quantify the sinusoidal and bile canalicular network in healthy male and female porcine livers and to map the variability of these structures with heterogenous distribution to improve the evaluability of liver biopsy samples.
METHODS: Livers from 12 healthy piglets (6 females and 6 neutered males) were sampled into 36 tissue samples per organ, representing six hepatic lobes and three different regions related to the hepatic vasculature (peripheral, paracaval and paraportal region). Histological sections were processed with a random orientation of the cutting plane. The endothelium and the bile canaliculi were stained using Ricinus communis agglutinin I lectin histochemistry. The length densities of hepatic sinusoids LV(sinusoids,liver), of bile canaliculi LV(bile canaliculi,liver) and volume fraction VV(sinusoids,liver) and surface density SV(sinusoids,liver) of sinusoids were estimated using stereological methods. The newly acquired morphometric data were compared with previously published data on density of porcine hepatocytes and fractions of connective tissue.
RESULTS: The peripheral region had smallest LV(sinusoids,liver), smallest LV(bile canaliculi,liver) and greatest VV(sinusoids,liver). The six hepatic lobes had statistically comparable length densities of both sinusoids and bile canaliculi, but the left lateral lobe had smallest VV(sinusoids,liver). Regions with greater LV(sinusoids,liver) had also greater LV(bile canaliculi,liver) and SV(sinusoids,liver) and were accompanied by greater density of smaller hepatocytes. Regions with smaller LV(sinusoids,liver) and LV(bile canaliculi,liver) contained a greater fraction of interlobular connective tissue.
CONCLUSIONS: The length density of hepatic sinusoids is smaller in the peripheral regions of the porcine liver than in other regions related to the hepatic vasculature - paracaval and paraportal regions, and smaller in castrated males than in females. Greater length density of liver sinusoids was linked with greater local density of bile canaliculi, with local increase in the density of smaller hepatocytes and, simultaneously, with smaller fractions of hepatic connective tissue. The intrahepatic and inter-sexual variability of the porcine liver morphology needs to be taken into account when designing and interpreting experiments involving the histological quantification of the microvascular network. The complete primary morphometric data describing the distribution of morphometric parameters within porcine liver were made available in a form facilitating the power analysis to justify the minimal number of tissue samples or animals required when designing further histological evaluation studies. The macroscopic map of microvessels and bile canaliculi variability facilitates their assessment in liver biopsies in the pig.
METHODS: Livers from 12 healthy piglets (6 females and 6 neutered males) were sampled into 36 tissue samples per organ, representing six hepatic lobes and three different regions related to the hepatic vasculature (peripheral, paracaval and paraportal region). Histological sections were processed with a random orientation of the cutting plane. The endothelium and the bile canaliculi were stained using Ricinus communis agglutinin I lectin histochemistry. The length densities of hepatic sinusoids LV(sinusoids,liver), of bile canaliculi LV(bile canaliculi,liver) and volume fraction VV(sinusoids,liver) and surface density SV(sinusoids,liver) of sinusoids were estimated using stereological methods. The newly acquired morphometric data were compared with previously published data on density of porcine hepatocytes and fractions of connective tissue.
RESULTS: The peripheral region had smallest LV(sinusoids,liver), smallest LV(bile canaliculi,liver) and greatest VV(sinusoids,liver). The six hepatic lobes had statistically comparable length densities of both sinusoids and bile canaliculi, but the left lateral lobe had smallest VV(sinusoids,liver). Regions with greater LV(sinusoids,liver) had also greater LV(bile canaliculi,liver) and SV(sinusoids,liver) and were accompanied by greater density of smaller hepatocytes. Regions with smaller LV(sinusoids,liver) and LV(bile canaliculi,liver) contained a greater fraction of interlobular connective tissue.
CONCLUSIONS: The length density of hepatic sinusoids is smaller in the peripheral regions of the porcine liver than in other regions related to the hepatic vasculature - paracaval and paraportal regions, and smaller in castrated males than in females. Greater length density of liver sinusoids was linked with greater local density of bile canaliculi, with local increase in the density of smaller hepatocytes and, simultaneously, with smaller fractions of hepatic connective tissue. The intrahepatic and inter-sexual variability of the porcine liver morphology needs to be taken into account when designing and interpreting experiments involving the histological quantification of the microvascular network. The complete primary morphometric data describing the distribution of morphometric parameters within porcine liver were made available in a form facilitating the power analysis to justify the minimal number of tissue samples or animals required when designing further histological evaluation studies. The macroscopic map of microvessels and bile canaliculi variability facilitates their assessment in liver biopsies in the pig.
摘要：
背景：猪肝作为一种与人类具有许多解剖学和生理学相似性的大型动物模型被广泛用于肝脏研究。然而,关于猪肝空间微观结构的信息有限，特别是关于肝窦和胆管。我们研究的目的是量化健康的雄性和雌性猪肝中的正弦和胆管网络，并绘制具有异质分布的这些结构的变异性，以提高肝活检样本的可评估性。
方法：将12只健康仔猪（6只雌性和6只绝育雄性）的肝脏取样到每个器官的36个组织样本中，代表六个肝叶和三个与肝脉管系统相关的不同区域(外周，旁和旁区域)。用随机取向的切割平面处理组织学切片。使用蓖麻凝集素I凝集素组织化学对内皮和胆管进行染色。肝窦LV的长度密度(正弦曲线，肝脏),胆管LV(胆管，肝脏)和体积分数VV(正弦，肝脏)和表面密度SV(正弦，肝）的正弦是使用体视学方法估计的。将新获得的形态测量数据与先前发表的有关猪肝细胞密度和结缔组织分数的数据进行比较。
结果：周围区域的LV最小（正弦曲线，肝脏),最小的LV（胆管，肝脏)和最大VV(正弦，liver).六个肝叶的正弦和胆小管的长度密度在统计学上相当，但是左侧叶的VV最小(正弦曲线，liver).具有较大LV(正弦曲线,肝脏）也有更大的LV（胆管，肝脏)和SV(正弦，肝脏），并伴有较小肝细胞的较大密度。LV较小的区域(正弦曲线，肝脏)和LV(胆管，肝脏）包含更大比例的小叶间结缔组织。
结论：猪肝外周区域的肝血窦长度密度小于与肝血管相关的其他区域——腔旁和门旁区域，而去势男性的肝血窦长度密度小于女性。肝窦的长度密度较大与胆小管的局部密度较大有关，随着小肝细胞密度的局部增加，同时,肝结缔组织的分数较小。在设计和解释涉及微血管网络组织学定量的实验时，需要考虑猪肝形态的肝内和性交变异性。描述猪肝脏内形态计量学参数分布的完整初级形态计量学数据以有助于功率分析的形式提供,以证明在设计进一步的组织学评估研究时所需的最少数量的组织样品或动物。微血管和胆小管变异性的宏观图有助于在猪的肝活检中进行评估。
方法：将12只健康仔猪（6只雌性和6只绝育雄性）的肝脏取样到每个器官的36个组织样本中，代表六个肝叶和三个与肝脉管系统相关的不同区域(外周，旁和旁区域)。用随机取向的切割平面处理组织学切片。使用蓖麻凝集素I凝集素组织化学对内皮和胆管进行染色。肝窦LV的长度密度(正弦曲线，肝脏),胆管LV(胆管，肝脏)和体积分数VV(正弦，肝脏)和表面密度SV(正弦，肝）的正弦是使用体视学方法估计的。将新获得的形态测量数据与先前发表的有关猪肝细胞密度和结缔组织分数的数据进行比较。
结果：周围区域的LV最小（正弦曲线，肝脏),最小的LV（胆管，肝脏)和最大VV(正弦，liver).六个肝叶的正弦和胆小管的长度密度在统计学上相当，但是左侧叶的VV最小(正弦曲线，liver).具有较大LV(正弦曲线,肝脏）也有更大的LV（胆管，肝脏)和SV(正弦，肝脏），并伴有较小肝细胞的较大密度。LV较小的区域(正弦曲线，肝脏)和LV(胆管，肝脏）包含更大比例的小叶间结缔组织。
结论：猪肝外周区域的肝血窦长度密度小于与肝血管相关的其他区域——腔旁和门旁区域，而去势男性的肝血窦长度密度小于女性。肝窦的长度密度较大与胆小管的局部密度较大有关，随着小肝细胞密度的局部增加，同时,肝结缔组织的分数较小。在设计和解释涉及微血管网络组织学定量的实验时，需要考虑猪肝形态的肝内和性交变异性。描述猪肝脏内形态计量学参数分布的完整初级形态计量学数据以有助于功率分析的形式提供,以证明在设计进一步的组织学评估研究时所需的最少数量的组织样品或动物。微血管和胆小管变异性的宏观图有助于在猪的肝活检中进行评估。
