Abstract

Introduction: Diacylglycerol lipase alpha (DAGLa) is an enzyme producing endocannabinoid 2-AG, the main endogenous ligand of CB1 receptors in the central nervous system. In regions that are relevant for the energy balance, such as the hypothalamus the expression of the enzyme DAGLa has been discretely studied. The wall of the third ventricle (3V), is cover by a group of cells denominated tanycytes, wich contact the cerebrospinal fluid (CSF) and through its processes take contact with the arcuate nucleus neurons. Therefore these cells metabolically coupling this cerebral region with the levels of peripheral molecules that reach the CSF in response to the energetic state. Materials and methods: Western blot and immunohistochemistry (IHC) were performed in basal hypothalamus sections of adult rats under several glycemic conditions to evaluate the expression and localization of DAGLa. Additionally, qRT-PCR and immunocytochemistry (ICC) were performed in tanycyte cultures incubated at 2, 5 and 15 mM glucose for 2h, to evaluate the mRNA and protein expression respectively. In addition, we evaluate the expression of Monoacylglycerol lipase (MAGL), enzyme that degrades 2-AG. Results: Using western blot, RT-PCR and immunohistochemistry we demonstrated the expression of DAGLa in the basal hypothalamus. In tanycytes cultures exposed at 15 mM glucose, we observed an increase in the expression of DAGLa mRNA. Additionally, the animals exposed to the hyperglycemia condition showed an increase of DAGLa protein. Discussion: The application of qRT-PCR, Western blot and immunolocalization techniques make it possible to demonstrate that the enzyme is expressed and located in tanycytes, suggesting that these glial cells can generate endocannabinoids and signal neurons of the arcuate nucleus to regulate food intake.