Investigation of the use of positron emission tomography for neuroreceptor imaging in rabbit eyes.
To determine whether positron emission tomography (PET) can be used for imaging of neuroreceptors in eyes of rabbits. PET imaging of dopamine D(2) receptor, dopamine transporter, serotonin(1A) receptor and sigma(1) receptor in the eyes and brain was performed using corresponding positron-emitting ligands in baseline, pretreatment and displacement conditions. The 4 radioligands outlined the eyes and brain in the baseline. Pretreatment resulted in a slight reduction (26-28%) in the uptake in the anterior segments of eyes. The binding of each radioligand in the iris-ciliary body and retina was confirmed by ex vivo autoradiography. However, the PET signal in the eyes was unexpectedly higher than the autoradiography signal. The identification of radioligand-neuroreceptor binding by PET in the rabbit eyes is not specific enough.
Wang
Wei-Fang
WF
Positron Medical Center, Tokyo Metropolitan Institute of Gerontology, Japan.
Ishiwata
Kiichi
K
Kiyosawa
Motohiro
M
Kawamura
Kazunori
K
Oda
Keiichi
K
Matsuno
Kiyoshi
K
Kobayashi
Tadayuki
T
Mochizuki
Manabu
M
D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000000981:diagnostic imaging; D002924:Ciliary Body / Q000000981:diagnostic imaging; D050483:Dopamine Plasma Membrane Transport Proteins; D005123:Eye / Q000000981:diagnostic imaging*; D007498:Iris / Q000000981:diagnostic imaging; D008297:Male; D008562:Membrane Glycoproteins / Q000032:analysis*; D026901:Membrane Transport Proteins / Q000032:analysis*; D009419:Nerve Tissue Proteins / Q000032:analysis*; D049268:Positron-Emission Tomography; D011817:Rabbits; D011869:Radioligand Assay; D044282:Receptor, Serotonin, 5-HT1A / Q000032:analysis*; D017448:Receptors, Dopamine D2 / Q000032:analysis*; D017480:Receptors, sigma / Q000032:analysis*; D012160:Retina / Q000000981:diagnostic imaging
D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D017448:Receptors, Dopamine D2; D017480:Receptors, sigma; D044282:Receptor, Serotonin, 5-HT1A