5-I-R91150 Explained

5-I-R91150 (or R93274) is a compound that acts as a potent and selective antagonist of 5-HT_2A receptors.^[1] Its main application is as its iodine-123 radiolabeled form, in which it can be used in SPECT scanning^[2] in human neuroimaging studies, to examine the distribution of the 5-HT_2A receptor subtype in the brain, e.g. with respect to sex and age^[3] and in adults with Asperger syndrome^[4] or Alzheimer's disease.^[5]

An alternative 5-HT_2A receptor ligand also used in neuroimaging is altanserin.

Further reading

• Catafau AM, Danus M, Bullich S, Llop J, Perich J, Cunningham VJ, Plaza P, Penengo MM, Eersels JL, Squassante L, Ros D, Barbanoj M . 6 . Characterization of the SPECT 5-HT2A receptor ligand 123I-R91150 in healthy volunteers: Part 1--pseudoequilibrium interval and quantification methods . Journal of Nuclear Medicine . 47 . 6 . 919–28 . June 2006 . 16741300 .
• Catafau AM, Danus M, Bullich S, Nucci G, Llop J, Abanades S, Cunningham VJ, Eersels JL, Pavia J, Farre M . 6 . Characterization of the SPECT 5-HT2A receptor ligand 123I-R91150 in healthy volunteers: part 2--ketanserin displacement . Journal of Nuclear Medicine . 47 . 6 . 929–37 . June 2006 . 16741301 .

Notes and References

1. Peremans K, Audenaert K, Coopman F, Jacobs F, Dumont F, Slegers G, Verschooten F, van Bree H, Mertens J, Dierckx R . 6 . Regional binding index of the radiolabeled selective 5-HT2A antagonist 123I-5-I-R91150 in the normal canine brain imaged with single photon emission computed tomography . Veterinary Radiology & Ultrasound . 44 . 3 . 344–51 . 2003 . 12816380 . 10.1111/j.1740-8261.2003.tb00467.x . free .
2. Busatto GF, Pilowsky LS, Costa DC, Mertens J, Terriere D, Ell PJ, Mulligan R, Travis MJ, Leysen JE, Lui D, Gacinovic S, Waddington W, Lingford-Hughes A, Kerwin RW . 6 . Initial evaluation of 123I-5-I-R91150, a selective 5-HT2A ligand for single-photon emission tomography, in healthy human subjects . European Journal of Nuclear Medicine . 24 . 2 . 119–24 . February 1997 . 9021107 . 10.1007/BF02439542 . 33466680 .
3. Baeken C, D'haenen H, Flamen P, Mertens J, Terriere D, Chavatte K, Boumon R, Bossuyt A . 6 . 123I-5-I-R91150, a new single-photon emission tomography ligand for 5-HT2A receptors: influence of age and gender in healthy subjects . European Journal of Nuclear Medicine . 25 . 12 . 1617–22 . December 1998 . 9871092 . 10.1007/s002590050339 . 29644617 .
4. Murphy DG, Daly E, Schmitz N, Toal F, Murphy K, Curran S, Erlandsson K, Eersels J, Kerwin R, Ell P, Travis M . 6 . Cortical serotonin 5-HT2A receptor binding and social communication in adults with Asperger's syndrome: an in vivo SPECT study . The American Journal of Psychiatry . 163 . 5 . 934–6 . May 2006 . 16648340 . 10.1176/appi.ajp.163.5.934 .
5. Versijpt J, Van Laere KJ, Dumont F, Decoo D, Vandecapelle M, Santens P, Goethals I, Audenaert K, Slegers G, Dierckx RA, Korf J . 6 . Imaging of the 5-HT2A system: age-, gender-, and Alzheimer's disease-related findings . Neurobiology of Aging . 24 . 4 . 553–61 . 2003 . 12714112 . 10.1016/S0197-4580(02)00137-9 . 44937787 .