Dopamine D2-receptor imaging with 123I-iodobenzamide SPECT in migraine patients abusing ergotamine: does ergotamine cross the blood brain barrier?
Two migraine patients were studied by in vivo SPECT using the dopamine D2-receptor specific radioligand 123I-3-iodo-6-methoxybenzamide (123I-IBZM) during ergotamine abuse and after withdrawal. Results were compared with 15 healthy controls. Striatum/cerebellum and striatum/occipital cortex ratios of count rate density were calculated as a semiquantitative measurement for striatal dopamine D2-receptor binding potential. No differences were found in striatal uptake of 123I-IBZM between healthy controls and the patients when on or off ergotamine. Preliminary evidence suggests that ergotamine may not occupy striatal dopamine D2-receptors to a large extent and thus may not cross the blood brain barrier in large quantities.
Verhoeff
N P
NP
Department of Nuclear Medicine, Academic Medical Centre, Amsterdam, The Netherlands.
Visser
W H
WH
Ferrari
M D
MD
Saxena
P R
PR
van Royen
E A
EA
D001549:Benzamides; D001812:Blood-Brain Barrier; D001921:Brain / Q000000981:diagnostic imaging*; D003287:Contrast Media; D065127:Dopamine D2 Receptor Antagonists; D004878:Ergotamine / Q000009:adverse effects / Q000493:pharmacokinetics* / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007457:Iodine Radioisotopes; D008297:Male; D008875:Middle Aged; D008881:Migraine Disorders / Q000000981:diagnostic imaging* / Q000188:drug therapy / Q000378:metabolism*; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2 / Q000032:analysis*; D013375:Substance Withdrawal Syndrome / Q000378:metabolism; D019966:Substance-Related Disorders / Q000378:metabolism; D015899:Tomography, Emission-Computed, Single-Photon
D001549:Benzamides; D003287:Contrast Media; D065127:Dopamine D2 Receptor Antagonists; D007457:Iodine Radioisotopes; D011759:Pyrrolidines; D017448:Receptors, Dopamine D2; C055743:3-iodo-2-hydroxy-6-methoxy-N-((1-ethyl-2-pyrrolidinyl)methyl)benzamide; D004878:Ergotamine