Abstract
Cholecystokinin (CCK) regulates various gastrointestinal functions through specific receptors. The mechanisms responsible for disorders of these functions could be elucidated by non-invasively localizing CCK receptors and quantifying their number in vivo. MK-329 is a highly selective and very high affinity antagonist at the peripheral CCK receptor. We investigated the in vivo binding of [3H](±)-MK-329 in mice to determine if binding to CCK receptors could be detected after systemic administration of the tracer. The uptake of [3H](±)-MK-329 increased in the pancreas from 5 min to 4 h after administration. The binding was saturable, stereospecific, and more than 80% specific. A total/non-specific binding ratio of 43 was reached at 8 h post-injection. The pancreas was the only organ where specific binding could be detected. Our results suggest that MK-329 labeled with a positron emitter such as C-11 could be used with positron emission tomography to image and quantify peripheral CCK receptors in man.
Original language | English (US) |
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Pages (from-to) | 195-201 |
Number of pages | 7 |
Journal | European Journal of Pharmacology |
Volume | 185 |
Issue number | 2-3 |
DOIs | |
State | Published - Aug 28 1990 |
Keywords
- (In vivo binding)
- CCK receptor antagonists
- CCK receptors (peripheral)
- MK-329
- PET (positron emission tomography)
- Pancreas
ASJC Scopus subject areas
- Pharmacology