Abstract
125I-2′-iodospiperone (2′-ISP), which has a high and selective affinity for dopamine D2 receptors, produced a high myocardial accumulation of radioactivity in the early phase after intravenous injection into mice. A human scintigraphic study also showed that the myocardium was clearly visualized soon after intravenous injection of the tracer. Analysis of the myocardial homogenate obtained from mice showed that125I-2′-ISP was metabolically stable and was taken up the myocardium in its intact form. Administration of spiperone significantly reduced the myocardial uptake of125I-2′-ISP in mice. Treatment with haloperidol and (+) butaclamol, which have a high affinity for dopamine D2 receptors, also tended to reduce the myocardial uptake of radioactivity, while (−)-butaclamol, which has no affinity for dopamine D2 receptors, caused no change in uptake. These findings suggest that the myocardial accumulation of 2′-ISP occurred in association with dopamine D2 (DA2) receptors.
Similar content being viewed by others
References
Nakatsuka I, Saji H, Shiba K, et al: In vitro evaluation of radioiodinated butyrophenones as radio-tracer for dopamine receptor study.Life Sci 41: 1989–1997, 1987
Saji H, Nakatsuka I, Shiba K, et al: Radioiodinated 2′-iodospiperone: a new radioligand for in vivo dopamine receptor study.Life Sci 41: 1999–2006, 1987
Saji H, Iida Y, Magata Y, et al: Preparation of123I-labeled 2′-iodospiperone and imaging of D2 dopamine receptors in the human brain using SPECT.Nucl Med Biol 19: 523–529, 1992
Murphy MB, Bass AS, Goldberg LI: Modulation of the dopaminergic system in cardiovascular therapeutics. In Enzymes as Targets for Drug Design, Palfreyman MG, McCann PP, Lovenberg W, Temple JG, Sjoerdsma A, (eds), San Diego,Academic Press, pp 17–29, 1990
Terai M, Usuda S, Maeno H: Dopamine receptors.Protein Nucleic Acid Enzyme 29: 1328–1337, 1984
Eckelman WC, Grissom M, Conklin J, et al: In vivo competition studies with analogues of 3-quinuclidinyl benzilate.J Pharm Sci 73: 529–534, 1984
Syrota A, Comar D, Paillotin G, et al: Muscarinic cholinergic receptor in the human heart evidenced under physiological conditions by positron emission tomography.Proc Natl Acad Sci USA: 82: 584–588, 1985
Eckelman WC, Reba RC, Gibson RE, et al: Receptor-binding radiotracers: a class of potential radiopharmaceuticals.J Nucl Med 20: 350–357, 1979
Kung HF: Radiopharmaceuticals for CNS receptor imaging with SPECT.Nucl Med Biol 17: 85–92, 1990
Beer HF, Blauenstein PA, Hasler PH, et al: In vitro and in vivo evaluation of iodine-123-Ro 16-0154: a new imaging agent for SPECT investigations of benzodiazepine receptors.J Nucl Med 31: 1007–1014, 1990
Pappata S, Cornu P, Samson Y, et al: PET study of carbon-11-PK 11195 binding to peripheral type benzodiazepine sites in glioblastoma: a case report.J Nucl Med 32: 1608–1610, 1991
Rogers GA, Parsons SM: Very high-affinity analogs of vesamicol, and an acetylcholine storage inhibitor.Neuroreport 1: 11–14, 1990
Efange SMN, Dutta AK, Michelson RH, et al: Radioiodinated 2-hydroxy-3-4(-iodophenyl)-1-(4-phenylpiperidinyl)propane: poteitial radiotracer for mapping central cholinergic innervation in vivo.Nucl Med Biol 19: 337–348, 1992
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Saji, H., Yonekura, Y., Tanahashi, K. et al. Myocardial accumulation of a dopamine D2 receptorbinding radioligand, 2′-iodospiperone. Ann Nucl Med 7, 153–156 (1993). https://doi.org/10.1007/BF03164959
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF03164959