Department of Pharmacology and Clinical Neuroscience, Umeå University, Umeå, Sweden.
FEBS J. 2013 May;280(9):1895-904. doi: 10.1111/febs.12212. Epub 2013 Mar 18.
Endocannabinoids are readily accumulated from the extracellular space by cells. Although their uptake properties have the appearance of a process of facilitated diffusion, it is by no means clear as to whether there is a plasma membrane transporter dedicated to this task. Intracellular carrier proteins that shuttle the endocannabinoid anandamide from the plasma membrane to its intracellular targets such as the metabolic enzyme, fatty acid amide hydrolase, have been identified. These include proteins with other primary functions, such as fatty-acid-binding proteins and heat shock protein 70, and possibly a fatty acid amide hydrolase-like anandamide transporter protein. Thus, anandamide uptake can be adequately described as a diffusion process across the plasma membrane followed by intracellular carrier-mediated transport to effector molecules, catabolic enzymes and sequestration sites, although it is recognized that different cells are likely to utilize different mechanisms of endocannabinoid transport depending upon the utility of the endocannabinoid for the cell in question.
内源性大麻素可被细胞从细胞外间隙轻易地摄取。尽管其摄取特性表现为易化扩散过程，但尚不清楚是否存在专门负责该任务的质膜转运体。已经鉴定出将内源性大麻素花生四烯酸乙醇胺从质膜转运至其细胞内靶标（如代谢酶脂肪酸酰胺水解酶）的细胞内载体蛋白。这些包括具有其他主要功能的蛋白质，如脂肪酸结合蛋白和热休克蛋白 70，并且可能还有类似脂肪酸酰胺水解酶的花生四烯酸乙醇胺转运蛋白。因此，尽管人们认识到不同的细胞可能根据内源性大麻素对特定细胞的用途而利用不同的内源性大麻素转运机制，但可以充分将花生四烯酸乙醇胺摄取描述为穿过质膜的扩散过程，随后是细胞内载体介导的运输至效应分子、代谢酶和隔离部位。
