Table 7.

Binding affinity (K_i) and signaling efficiency (EC₅₀) of prostanoids and agonists on the recombinant TP receptors expressed in cell cultures and in human platelets, lung, and vascular smooth muscle

	Ki (nM)
Receptor	U46619	I-BOP	STA2	PGE2	PGF2a	Reference
hTP/HEK293a	35 ± 5	-	-	29,000 ± 6,702	8,700 ± 670	Abramovitz et al. 2000
hTP/HEK293b	100	16	-	2000c	5000c	Capra et al. 2013
hTP/COS-m6c	-	25	-	-	-	Hirata et al. 1996
mTP/CHOd	67	0.56	14	-	-	Sawyer et al. 2002, Kiriyama et al. 1997
hTP/plateletse	16 ± 5		-	-	-	Modesti et al. 1989
hTP/plateletse	39 ± 4.7	-	-	-	-	Miki et al. 1992
hTP/plateletsf	221 ± 21	-	87 ± 19	-	-	Armstrong et al. 1993
hTP/plateletsg	8.5 ± 2.5	0.21 ± 0.03	-	-	-	Dorn 1989
hTP/vascular smooth muscleg	88 ± 10	0.18 ± 0.02	-	-	-	Dorn 1991
hTP/purified in Tris/asolectine	19,900	-	870	-	-	Ushikubi et al. 1989a
	EC50 (nM)
Receptor	STA2	I-BOP	U46619	TXA2	PGH2	Reference
hTPα/COS-m6h	2	-	-	-	-	Hirata et al. 1996
hTPβ/COS-m6h	2	-	-	-	-	Hirata et al. 1996
hTPα/CHOi	-	17	-	-	-	Hirata et al. 1996
hTPβ/CHOi	-	NA	-	-	-	Hirata et al. 1996
hTP/CHOh	4	-	-	-	-	Hirata et al. 1994b
hTP/HEK293h	-	25	99	-	-	Capra et al. 2013
hTP/hand veinj	-	-	40	-	-	Arner et al. 1991
hTP/lung parenchymalk	-	-	32	-	-	McKenniff et al. 1988
hTP/bronchiolar ringl	-	-	16	-	-	McKenniff et al. 1988
hTP/plateletsm	-	0.209 ± 0.024	-	-	-	Dorn 1989
hTP/plateletsn	-	-	-	163 ± 21	45 ± 2	Mayeux et al. 1988
hTP/plateletsn	-	-	4.8 ± 0.2	-	-	Tymkewycz et al. 1991
hTP/plateletso	90	-	-	-	-	Ushikubi et al. 1989b

Abbreviations: h, human; HEK293, human embryonic kidney cells; COS M-6, Green monkey kidney cells; CHO. Chinese hamster ovary cells. The K_i values were determined from [³H]agonist displacement assays. The EC₅₀ determined from intracellular changes in IP₃, cAMP, [Ca²⁺] or the indicated physiological changes. NA= no activity. a) K_i determined from the displacement of [³H]SQ29548; b) IC₅₀ estimated from a graph of agonist vs. [³H]SQ29548 and the K_i value calculated using Cheng-Prusoff equation (Suganami et al. 2016); c) IC₅₀ estimated from graph of agonist vs. [³H]S-145 and the K_i value calculated using Cheng-Prusoff equation; d) K_i determined from the displacement of [³H]S-145; e) K_i determined from the displacement of [³H]U46619; f) K_i calculated from reported IC₅₀ of agonist vs [³H]SQ29548 using Cheng-Prusoff equation; g) K_i for high binding site calculated from IC₅₀ of agonist vs. [¹²⁵I]-BOP using Cheng-Prusoff equation; h) EC₅₀ determined from IP₃ generation; i) EC₅₀ determined from cAMP generation determined from titration curves; j) EC₅₀ determined from % maximal contraction of vein ring segments; k) EC₅₀ determined from % maximal contraction of lung parenchymal strip; l) EC₅₀ determined from % maximal contraction of bronchiolar ring segments; m) EC₅₀ determined from [Ca²⁺] increase; n) EC₅₀ determined from initiation of platelet aggregation; o) EC₅₀ determined from inhibition of PGI₂ analog iloprost (3 nM) induced cAMP increase.