mRNA expression of serotonin receptors in cells of the immune tissues of the rat.
Serotonin (5-hydroxytryptamine, 5-HT) has been shown to play a role in immunoregulation; however, little is known about specific subtypes of 5-HT receptors involved in peripheral immunomodulation. In the present study we used RT-PCR methods to examine the mRNA expression of 5-HT receptors in the cells of lymphoid tissues of the rat. All 13 rat 5-HT receptor genes cloned so far were examined in ex vivo isolated spleen, thymus, and peripheral blood lymphocytes, as well as in mitogen-stimulated spleen cells. Positive signals were obtained for 5-HT1B, 5-HT1F, 5-HT2A, 5-HT2B, 5-HT6, and 5-HT7 receptor mRNAs in all three compartments. Mitogen (ConA and PWM) stimulated cells additionally expressed mRNA corresponding to the 5HT-3 receptor subtype. In contrast, 5-HT1A, 5-HT1D, 5-HT2C, 5-HT4, 5-HT5A, and 5-HT5B mRNAs were not detected in any of the examined cell populations. These results may be useful as a starting point for future functional studies on immunomodulatory effects of 5-HT and may help to understand conflicting serotonergic effects on immune functions as found in the literature.
Stefulj
J
J
Department of Molecular Genetics, Rudjer Boskovic Institute, Bijenicka 54, Zagreb, HR-10000, Croatia.
Jernej
B
B
Cicin-Sain
L
L
Rinner
I
I
Schauenstein
K
K
D000818:Animals; D001773:Blood Cells / Q000378:metabolism; D003208:Concanavalin A / Q000494:pharmacology; D007107:Immune System / Q000378:metabolism*; D008214:Lymphocytes / Q000378:metabolism; D008221:Lymphoid Tissue / Q000378:metabolism*; D008297:Male; D011043:Pokeweed Mitogens / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011985:Receptors, Serotonin / Q000235:genetics*; D013154:Spleen / Q000166:cytology / Q000378:metabolism; D013950:Thymus Gland / Q000166:cytology / Q000378:metabolism
D011043:Pokeweed Mitogens; D012333:RNA, Messenger; D011985:Receptors, Serotonin; D003208:Concanavalin A