Detection of retinoic acid receptor mRNA in rat tissues by reverse transcriptase-polymerase chain reaction

The presence of retinoic acid receptor (RAR) alpha, beta and gamma mRNA was examined in 16 different kinds of rat tissue using the highly sensitive reverse transcriptase-polymerase chain reaction technique. The data demonstrated that each tissue expressed at least two types of RAR mRNA. Among the three types of RAR mRNA, RAR alpha was widely expressed in all types of organ and was the dominant form expressed in the gastrointestinal tract. RAR beta mRNA was not present in the intestine and spleen. In addition, RAR beta mRNA levels were high in the heart, lung, brain, testis and epididymis. RAR gamma mRNA was abundant in both male and female reproductive systems, as well as epidermal tissues. The prevalence of each RAR mRNA in the tissues suggests the diverse biological roles of these receptors.