Among the biological activities of the endocannabinoid anandamide (N-arachidonoylethanolamine) (AEA), growing interest has been attracted by the regulation of mammalian fertility. Recently we have shown that treatment of mouse primary Sertoli cells with FSH enhances the activity of the AEA hydrolase [fatty acid amide hydrolase (FAAH)], though the molecular details were not elucidated. Here, we investigated whether FSH was also able to affect the enzymes that synthesize AEA (N-acyltransferase and N-acyl-phosphatidylethanolamine- phospholipase D), the endogenous content of this endocannabinoid, and the level of the AEA-binding vanilloid receptor 1 (transient receptor potential channel vanilloid receptor subunit 1).Weshow thatFSHenhancedFAAH activity (up to 500% of the controls) and expression (up to 300%), leading to a marked reduction (down to15%) of AEA content. However N-acyltransferase and N-acyl-phosphatidyl- ethanolamine-phospholipase D activity, and transient receptor potential channel vanilloid receptor subunit 1 binding were not affected. We also show that diacylglycerol lipase and monoacylglycerol lipase, which respectively synthesize and degrade 2-arachidonoyl-glycerol, were not regulated by FSH, neither was themembranetransport of this endocannabinoid. In addition, we show that FAAH stimulation by FSH was abrogated by inhibitors of protein kinase A (PKA) and cytochrome- P450 aromatase, and was conversely mimicked by N,O’-dibutyryl cAMP and estrogen. Finally, we demonstrate that FSH protects Sertoli cells against the pro-apoptotic activity of AEA, through PKA and aromatase-dependent activation of FAAH. Altogether these data suggest that FAAH is the only target of FSH among the elements of the endocannabinoid system, and that its regulation by PKA and aromatasedependent pathways impacts Sertoli cell proliferation. (Endocrinology 148: 1431–1439, 2007)
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