Serotonin receptor subtype mRNA expression in human oculartissues, determined by RT-PCR

[摘要] Purpose: To determine the relative density and tissue localizationof mRNAs for serotonin (5-hydroxytryptamine; 5HT) receptor subtypes inhuman ocular tissues and correlate with their possible functions in theeye.Methods: Total RNA was extracted from human ocular tissues samplesfrom multiple donors and transcribed into cDNA. An optimized reversetranscriptase polymerase chain reaction (RT-PCR) procedure was then usedto amplify the signals using primers designed against human 5HT receptorcDNAs. The PCR products were analyzed by gel electrophoresis andconfirmed by endonuclease digestion.Results: Variable amounts of total RNA were extracted from differenttissues with the least amount from ciliary epithelium and most amountfrom retina. 5HT2 receptor subtype mRNAs were the most abundantwith 5HT2A and 5HT2B being the most predominant in theretina, ciliary body, ciliary epithelium, choroid, conjunctiva, andiris. Ciliary body, choroid, and conjunctiva were most enriched in5HT3 receptor mRNA, with relatively lower levels in the iris.5HT4 receptor mRNA was most enriched in the retina, ciliary body,choroid, conjunctiva, and somewhat detectable in the iris. 5HT5receptor mRNA was abundant in the retina, ciliary body, and iris.5HT6 receptor mRNA was the least abundant of all subtypes studiedand could only be detected in the iris. 5HT7 receptor mRNA wasenriched in the ciliary body, choroid, conjunctiva, and iris, with muchlower levels in the retina and ciliary epithelium. Optic nerve tissue of1-2 donors exhibited the presence of 5HT2B, 5HT5, and5HT7 receptor mRNAs. Data for human trabecular meshwork cellsindicated a high density of mRNAs for 5HT2A and 5HT2B, withmuch lower levels of 5HT2C, 5HT5, and 5HT7 receptormRNAs.Conclusions: Human ocular tissues differentially expressed mRNAs forthe various 5HT receptor subtypes. These studies suggest a diverse rangeof possible physiological and pharmacological functions of 5HT receptorsin these human ocular tissues.

[学科分类] 生物化学/生物物理