Table 2. Radioactivity Distribution 30 min Post-injection Determined by Counting after Dissection.

	Uptake index (±SEM)					Uptake inhibition (%)d
Tissue or BS	Baseline conditions	blocking with naloxonea	blocking with U50,488b	blocking with JDTicc	BS/CB ratio (baseline)	naloxone	U50,488	JDTic
Blood	0.25 ± 0.04	0.33 ± 0.09	0.24 ± 0.03	0.27 ± 0.04	nae	nae	nae	nae
Pituitary	8.06 ± 0.28	5.58 ± 0.48	5.61 ± 0.19	4.59 ± 0.67	nae	31	30	43
1/2 Brain	0.06 ± 0.01	0.05 ± 0.01	0.05 ± 0.01	0.06 ± 0.01	nae
HY	0.23 ± 0.07	0.17 ± 0.02	0.13 ± 0.02	0.17 ± 0.02	3.70 ± 1.31		43
OT	0.15 ± 0.03	0.17 ± 0.08	0.09 ± 0.01	0.13 ± 0.02	2.09 ± 0.30		40
CPU	0.12 ± 0.04	0.08 ± 0.01	0.13 ± 0.04	0.09 ± 0.01	1.61 ± 0.23	37
HIP	0.10 ± 0.01	0.09 ± 0.02	0.10 ± 0.01	0.10 ± 0.02	1.59 ± 0.39
CTX	0.09 ± 0.01	0.11 ± 0.05	0.08 ± 0.01	0.09 ± 0.01	1.31 ± 0.30
TH	0.08 ± 0.02	0.11 ± 0.06	0.06 ± 0.01	0.06 ± 0.01	1.11 ± 0.31
CB	0.07 ± 0.02	0.06 ± 0.01	0.07 ± 0.01	0.06 ± 0.01	1.00 ± 0.01

^aPreinjection of naloxone (1 mg/kg; iv; 10 min).

^bPreinjection of U-50,488 (1 mg/kg; iv; 10 min).

^cPreinjection of JDTic (10 mg/kg; ip; 30 min).

^dOnly values for significant inhibition (P < 0.041).

^eNot applicable.