Radiosynthesis and preclinical evaluation of [11C]prucalopride as a potential agonist PET ligand for the 5-HT4 receptor

EJNMMI Research

Table 2 Distribution of radioactivity in several brain regions and peripheral organs in rats

Organ/region	Percentage ID/g (mean ± SD, n= 4 per time point)
	5 min	15 min	30 min	60 min
Olfactory bulb	0.13 ± 0.04	0.05 ± 0.03	0.10 ± 0.05	0.04 ± 0.01
Striatum	0.07 ± 0.01	0.05 ± 0.02	0.08 ± 0.05	0.04 ± 0.01
Hippocampus	0.09 ± 0.02	0.05 ± 0.02	0.05 ± 0.01	0.03 ± 0.01
Medulla oblongata	0.06 ± 0.00	0.03 ± 0.01	0.05 ± 0.00	0.03 ± 0.00
Frontal cortex	0.06 ± 0.00	0.03 ± 0.02	0.03 ± 0.00	0.02 ± 0.00
Thalamic region	0.05 ± 0.00	0.03 ± 0.01	0.03 ± 0.01	0.02 ± 0.01
Posterior cortex	0.06 ± 0.01	0.04 ± 0.02	0.03 ± 0.01	0.03 ± 0.01
Rest of the brain	0.06 ± 0.00	0.03 ± 0.02	0.05 ± 0.00	0.03 ± 0.00
Cerebellum	0.08 ± 0.01	0.04 ± 0.02	0.04 ± 0.00	0.02 ±0.00
Liver	1.60 ± 0.58	1.32 ± 0.59	1.53 ± 0.19	0.83 ± 0.05
Kidney	2.57 ± 0.24	1.06 ± 0.49	0.79 ± 0.10	0.43 ± 0.04
Lungs	1.55 ± 0.61	0.51 ± 0.23	0.39 ± 0.13	0.24 ± 0.04
Colon	1.01 ± 0.29	0.54 ± 0.26	0.32 ± 0.07	0.22 ± 0.03
Heart	0.39 ±0.04	0.21 ± 0.10	0.19 ± 0.01	0.10 ± 0.01
Blood	0.16 ± 0.01	0.08 ± 0.04	0.10 ± 0.01	0.06 ± 0.00

Radioactivity is measured ex vivo at various time points following IV injection of 53 ± 2 MBq (SA 42 ± 8 GBq·μmol⁻¹) of [¹¹C]prucalopride. Tissue samples were not flushed with saline prior to the radioactivity measurement. Experiments were performed on two separate days, day 1 at 5 and 15 min and day 2 at 30 and 60 min.