3. Umbruch 4.4..2005 - Online Pot

Endocannabinoids and regulation of fertility 71
Figure 2. Interactions between blastocyst and uterine epithelium. At the site of implantation blastocysts
release a lipid compound able to activate fatty acid amide hydrolase (FAAH) in uterine epithelial
cells, termed the FAAH activator. This leads to the cleavage of anandamide (AEA), thus reducing
its uterine levels and noxious effects towards the implanting blastocyst (see also Fig. 1). AEA-synthesizing
phospholipase D (PLD), AEA membrane transporter (AMT) and AEA-binding type 1
cannabinoid receptors (CB 1Rs) of uterine epithelial cells are not modulated by the FAAH activator.
production of the activator by an unhealthy embryo might contribute to
implantation failure. Alternatively, a non-receptive, unhealthy uterus might be
unable to respond properly to a normal activator, leading to blastocyst death.
Though the molecular details of the embryo–uterine cross-talks remain to be
elucidated, present evidence strongly suggests that FAAH regulates these
cross-talks by controlling the endogenous tone of AEA.