Aquaporin-4 and spinal cord injury

Table 1 Studies of aquaporin-4 expression following spinal cord injury

Ref.	Species	Model	Device	Parameters	Level	AQP4 RNA	AQP4 protein	AQP4 IHC	Water content	Behavioral outcome
Nesic et al[53]	Sprague dawley male rats	Contusion	IH Impactor	200 kdyn	T10	↑ AQP4 at 28 d post SCI	↑ AQP4 at 28 d post SCI	↑ AQP4 at 28 d and 5 m post SCI		↑ CNP in animals with increased AQP4
Nesic et al[36]	Sprague dawley male rats	Contusion	IH Impactor	150 kdyn,	T13		↓ AQP4 at 12 h, 24 h, 3 d and 7 d post SCI	↑ AQP4 at 5 m post SCI	↑ levels at lesion site at 3 d
				1 s dwell			↑ AQP4 at 14 d, 35 d, 40 d, 56 d, 3.5 m and 9 m post SCI	Astrocytes lacking AQP4 at dpi 14	↑ levels at all levels at 2 and 5 mo
Nesic et al[47]	Human				C5/6, C2, C8			↑ AQP4 in spared white matter
								↓ AQP4 in lesion epicenter
								(1-2 yr post SCI)
	Sprague dawley male rats	Contusion	IH Impactor	150 kdyn,	T10		↑ AQP4 at 2 and 11 m post SCI	↑ AQP4-/GFAP+ astrocytes at 14 d post SCI	↑ levels at 3 d, 2 and 5 m	BBB outcome coorelated with severity of injury
				1 s dwell			↓ AQP4 in severe SCI at 21 d	↑ AQP4 labeling in AQP4+ astrocytes post SCI
							↓ AQP4 in moderate SCI at 1, 7 and 14 d	↑ AQP4 at 1, 2, 3 and 5 m post SCI
							no change in moderate/mild SCI at 21 d
Leonard et al[79]	Rabbits	Compression	Balloon compression	8 atm pressure,	T10			↑ AQP4 at 5 h, 24 h, 3 d and 14 d post SCI	↑ levels at 5 h, 24 h and 3 d	↓ Tarlov score and sensory pin prick in SCI animals
				5 min hold

AQP4: Aquaporin-4; IH: Infinite Horizons; BBB: Basso, Beattie, Bresnahan; CNP: Chronic neuropathic pain; GFAP: Glial fibrillary acidic protein; SCI: Spinal cord injury.