Kondo S, Sugiura T, Kodaka T, Kudo N, Waku K, Tokumura A
Faculty of Pharmaceutical Sciences, Teikyo University, Kanagawa, Sagamiko, 199-01, Japan.
Arch Biochem Biophys. 1998 Jun 15;354(2):303-10. doi: 10.1006/abbi.1998.0688.
Changes in the levels of various molecular species of N-acylethanolamine in CdCl2-administered rat testis were examined. We found that the levels of various N-acylethanolamines including anandamide (N-arachidonoylethanolamine), an endogenous cannabinoid receptor ligand, were dramatically increased in CdCl2-admin-istered rat testis. Such changes were particularlyprominent for saturated and monoenoic species such as N-palmitoyl species (39-fold at 9 h) and N-stearoyl species (21-fold at 9 h), compared with unsaturated fatty acid-containing species such as anandamide (5-fold at 9 h). Noticeably, increased levels were observed of not only N-acylethanolamines but also several species of N-acylphosphatidylethanolamine, potential precursors for N-acylethanolamines. We confirmed that the rat testis microsomal fraction contains phosphodiesterase activity catalyzing the release of N-acylethanolamine from N-acylphosphatidylethanolamine and transacylase activity catalyzing the formation of N-acylphosphatidylethanolamine from phosphatidylethanolamine and phosphatidylcholine. These enzyme activities were not dramatically different in the microsomal fraction obtained from CdCl2-administered rat testis compared with that in the case of control rat testis, at least when estimated in cell-free assay systems, suggesting that the accessibility of the substrates to the enzymes may be increased in CdCl2-administered rat testis to generate a large amount of N-acylethanolamine. Possible pathophysiological implications of the augmented generation of N-acylethanolamine including anandamide in CdCl2-administered rat testis were discussed.
研究了氯化镉处理的大鼠睾丸中N-酰基乙醇胺各种分子种类水平的变化。我们发现，包括内源性大麻素受体配体花生四烯酸乙醇胺（N-花生四烯酰基乙醇胺）在内的各种N-酰基乙醇胺水平在氯化镉处理的大鼠睾丸中显著升高。与含不饱和脂肪酸的种类如花生四烯酸乙醇胺（9小时时增加5倍）相比，饱和和单烯种类如N-棕榈酰基种类（9小时时增加39倍）和N-硬脂酰基种类（9小时时增加21倍）的变化尤为显著。值得注意的是，不仅N-酰基乙醇胺水平升高，而且几种N-酰基磷脂酰乙醇胺种类也有所增加，它们是N-酰基乙醇胺的潜在前体。我们证实大鼠睾丸微粒体部分含有催化从N-酰基磷脂酰乙醇胺释放N-酰基乙醇胺的磷酸二酯酶活性以及催化从磷脂酰乙醇胺和磷脂酰胆碱形成N-酰基磷脂酰乙醇胺的转酰基酶活性。与对照大鼠睾丸相比，从氯化镉处理的大鼠睾丸获得的微粒体部分中的这些酶活性没有显著差异，至少在无细胞测定系统中估计时是这样，这表明在氯化镉处理的大鼠睾丸中底物对酶的可及性可能增加，从而产生大量的N-酰基乙醇胺。讨论了在氯化镉处理的大鼠睾丸中包括花生四烯酸乙醇胺在内的N-酰基乙醇胺生成增加的可能病理生理意义。
