Table 1.

A₁AR ligands with antinociceptive effects in preclinical models of pain.

Ligand	Pharmacological Behavior	Pain Model	Species	Route of Administration
2′-Me-CCPA	agonist	formalin test	rat	intra-PAG, i.p. [20]
		plantar test	rat	intra-PAG, i.p. [20]
		tail flick test	rat	intra-PAG, i.p. [20]
CCPA	agonist	formalin test	mouse	i.p. [69]
		writhing test	mouse	i.p. [69]
		STZ-induced mechanical allodynia	mouse	i.p. [69]
		CFA induced-mechanical allodynia and thermal hyperalgesia	mouse	Zusanli acupoint-injection [28]
		SCNL induced-mechanical allodynia and thermal hyperalgesia	mouse	Zusanli acupoint-injection [28]
CPA	agonist	formalin test	mouse	i.p. [49]; i.t. [54]
		CFA-induced-mechanical allodynia and thermal hyperalgesia	mouse	i.m. [30]; i.p. [42]; Weizhong acupoint-injection [46]
		carrageenan-induced mechanical allodynia	rat	i.pl. [18]
		PGE2-induced mechanical allodynia	rat	i.pl. [18]
		SCNL-induced mechanical allodynia and thermal hyperalgesia	rat	i.p. [21]
		colonic distension-induced visceral pain	rat	s.c., i.c. [23,24]
R-PIA	agonist	plantar incision-induced mechanical allodynia	rat	i.t. [25]
		photochemical SCI-induced mechanical and thermal allodynia	rat	i.t. [47]
		SCNL-induced mechanical allodynia	rat	i.t. [50]
		photochemical sciatic nerve injury-induced mechanical and thermal allodynia	rat, mouse	i.t. [52]
		carrageenan-induced mechanical and thermal allodynia	rat, mouse	i.t. [52]
T62	positive allosteric modulator	SNL-induced mechanical allodynia	rat	i.p. [63]; i.t. [63,64]; p.o. [64]
		carrageenan-induced thermal hyperalgesia	rat	i.t. [65]
		plantar incision-induced mechanical allodynia	rat	i.t. [66]
TRR469	positive allosteric modulator	formalin test	mouse	i.p. [69]
		writhing test	mouse	i.p. [69]
		STZ-induced mechanical allodynia	mouse	i.p. [69]

PAG (periaqueductal grey); i.p. (intraperitoneal); STZ (streptozotocin); CFA (Complete Freund’s adjuvant); SCNL (sciatic nerve ligation); i.t. (intrathecal); i.m. (intramuscular); i.pl. (intraplantar); s.c. (subcutaneous); i.c. (intracisternal); SCI (spinal cord injury); SNL (spinal nerve ligation); p.o. (per os).