Table 4.

Operational parameters describing DOR agonist responses in cAMP accumulation and internalization assays carried out in HEK293 cells

Internalization
	log KA ± SEM (M)	log τ ± SEM	log (τ/KA) ± SEM
SNC-80 (n = 12)	−4.28 ± 0.38a,b,c	1.23 ± 0.33e,f	5.51 ± 0.50i,i
DPDPE (n = 11)	−6.12 ± 0.10d	0.72 ± 0.07 g,h	6.85 ± 0.13
UFP-512 (n = 10)	−6.85 ± 0.23	−0.95 ± 0.04	5.90 ± 0.24
Morphine (n = 11)	N/A	N/A	N/A
TIPP (n = 9)	−7.83 ± 0.33	−1.00 ± 0.04	6.83 ± 0.33

Statistical comparisons among drugs done using one-way ANOVA followed by Bonferroni post hoc tests

N/A not applicable, minimal effect by morphine prevented meaningful curve fitting

Log KA comparisons

^aSNC-80 vs. DPDPE p < 0.01

^bSNC-80 vs. UFP-512 p < 0.001

^cSNC-80 vs. TIPP p < 0.001

^dDPDPE vs. TIPP p < 0.01

Log τ comparisons

^eSNC-80 vs. UFP-512 p < 0.001

^fSNC-80 vs. TIPP p < 0.001

^gDPDPE vs. UFP-512 p < 0.001

^hDPDPE vs. TIPP p < 0.001

Log τ/KA comparisons

ⁱSNC-80 vs. DPDPE p < 0.01

^jSNC-80 vs. TIPP p < 0.05