New in-situ hybridization method measuring serotonin 2A (5-HT2A) receptor mRNA levels in rats exposed to MDMA

This study aimed to identify changes in the expression of serotonin (5-hydroxytryptamine; 5-HT) receptor 5-HT2a mRNA in paraformaldehyde prefixed rat brain tissue after exposure to 3, 4 methylenedioxymethamphetamine (MDMA). Rather than use traditional, time-consuming methods that were highly prone to error, such as the use of radioactive riboprobes, we used recent advancements in the development of rapid in-situ hybridization to our advantage. The use of rapid in-situ hybridization (such as the RNAscope assay) has allowed us to use paraformaldehyde prefixed brain tissue sections, which are more widely available and easier to use, instead of fresh frozen tissue. Here we describe the results from the use of the RNAscope assay to measure the amount of dapB (a bacterial gene), ppiB (a eukaryotic housekeeping gene), and htr2a (a eukaryotic gene coding for 5-HT2A receptors) mRNA.