Tissue and species differences in bile salt-dependent neutral cholesteryl ester hydrolase activity and gene expression.
Tissue and species differences in bile salt-dependent neutral cholesteryl ester hydrolase activity and gene expression.
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DOI：
10.1161/01.atv.12.3.295
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发表时间：
1992-03
期刊：
影响因子：
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通讯作者：
R. Zolfaghari;E. Harrison;J. Han;W. Rutter;E. Fisher
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文献类型：
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作者：
R. Zolfaghari;E. Harrison;J. Han;W. Rutter;E. Fisher
在大鼠和兔组织中测定中性胆盐依赖性胆固醇酯水解酶（CEH）的酶活性和mRNA丰度。在大鼠肝脏和肠道中，酶活性和mRNA水平独立变化。在大多数组织样品中特别引人注目的是，在酶活性存在的情况下，没有可检测到的CEH mRNA，这表明存在酶的外源性来源。兔子和老鼠有四个方面的不同。首先，任何肝脏样本中都不存在CEH活性和mRNA。第二，CEH mRNA存在于几乎所有的肠道样品中，其丰度往往与酶活性相关。第三，兔CEH mRNA比大鼠短约250个碱基。第四，我们以前已经表明，大鼠血浆中含有CEH活性，而在本研究中，兔血浆中不含这种活性。总的来说，我们的研究表明，大鼠肝脏，肠道和血浆中的CEH活性可以来自外源性的，最有可能从胰腺酶的摄取和运输。相比之下，在兔中，血浆和肝脏中缺乏CEH活性以及肠原位合成CEH的能力表明该动物不具有相同的分配胰腺CEH的能力。CEH代谢的这些种属差异可能部分解释了家兔组织对胆固醇酯蓄积的更大敏感性。
Enzymatic activity and mRNA abundance for neutral bile salt-dependent cholesteryl ester hydrolase (CEH) were determined in rat and rabbit tissues. In rat liver and intestine, enzyme activity and mRNA levels varied independently. Particularly striking in most tissue samples was the absence of detectable CEH mRNA in the presence of enzymatic activity, suggesting that there was an exogenous source of enzyme. Rabbits differed from rats in four ways. First, neither CEH activity nor mRNA was present in any liver sample. Second, CEH mRNA was present in nearly all intestinal samples, and its abundance tended to correlate with enzymatic activity. Third, rabbit CEH mRNA was approximately 250 bases shorter than the rat message. Fourth, we have previously shown that rat plasma contains CEH activity, whereas in the present studies, rabbit plasma did not contain such activity. Overall, our studies indicate that CEH activity in rat liver, intestine, and plasma can be derived exogenously, most likely from the uptake and transport of pancreatic enzyme. In contrast, in rabbit the lack of CEH activity in plasma and liver and the capacity of the intestine for in situ synthesis of CEH suggest that this animal does not have the same ability to distribute pancreatic CEH. These species differences in CEH metabolism may partly explain the greater susceptibility of rabbit tissues to accumulate cholesteryl esters.