Schematic and qualitative representation of the results of the RT-PCR analyses of mRNAs for cannabinoid and vanilloid receptors in the cell lines under study
Total RNA from cells was extracted, and its integrity was verified. RNA was further treated with RNase-free DNase I (Ambion DNA-free kit) to digest contaminating genomic DNA and to subsequently remove the DNase and divalent cations. The expression of mRNAs was examined by RT-PCR. Transcripts for fatty acid amide hydrolase (FAAH) and CB1 and CB2 receptors were analyzed and are classified as: a, abundant; m, medium; w, weak; and nd, not detected, based on the intensity of the band normalized to the band corresponding to glyceraldehyde-3-phosphate dehydrogenase as the housekeeping gene and on the number of cycles necessary to obtain a visible band. Results are based on n = 3 separate determinations.