Prenatal developmental expression of rat brain 5-HT1A receptor gene followed by PCR.

Expression of the gene encoding the serotonin 5-HT1A receptor was investigated in the brain of rats from embryonic day (ED) 10 to postnatal day 18 using PCR. The 5-HT1A receptor transcripts were first detected as early as ED 12. Their concentration increased to a maximum at ED 15 and decreased progressively to very low levels just before birth (ED 20). In 18-day-old rats, the brain stem levels of 5-HT1A receptor mRNA were higher than at ED 20 but still markedly lower than at ED 15. The high rate of expression of the 5-HT1A receptor gene for a limited period during the fetal life further supports that this receptor might be involved in the trophic action of serotonin during brain maturation.