Table 3. Glomerular filtration rate (GFR) and fractional electrolyte excretion prior to (baseline) and after intervention (Tempol, PEG-catalase, vehicle).

	CON		CKD		P-value
	baseline	Tempol	baseline	Tempol	CKD-cat	Tempol	Interaction
N	4		6
GFR (µl/min/100g)	672±65	485±60 $$	302±18 ###	262±21 ##	<0.001	= 0.003	= 0.029
FE Na (%)	0.28±0.12	0.23±0.13	1.02±0.26	1.91±0.54 # $$	= 0.042	= 0.066	= 0.043
FE K (%)	26.09±1.94	25.11±0.73	64.22±4.61 ###	62.43±3.90 ###	<0.001	= 0.665	= 0.898
	baseline	PEG-catalase	baseline	PEG-catalase	CKD	PEG-catalase	Interaction
N	5		8
GFR (µl/min/100g)	784±105	510±112 &&&	354±40 ###	273±24 ##	<0.001	<0.001	= 0.021
FE Na (%)	0.15±0.04	0.12±0.04	0.47±0.08	0.79±0.14 ### &&&	= 0.005	= 0.026	= 0.009
FE K (%)	30.47±3.53	28.67±3.56	63.42±5.41 ###	60.96±4.98 ###	<0.001	= 0.501	= 0.915
	baseline	vehicle	baseline	vehicle	CKD	vehicle	Interaction
N	4		4
GFR (µl/min/100g)	741±102.13	523±107 §	303±32 ##	240±28 #	= 0.013	= 0.007	= 0.066
FE Na (%)	0.17±0.04	0.16±0.05	1.27±0.60	1.60±0.92	= 0.145	= 0.364	= 0.342
FE K (%)	30.67±0.79	26.77±1.94	73.50 ±8.58 ##	73.45±7.64 ##	= 0.001	= 0.273	= 0.284

Mean ± SEM, ANOVA RM, Tukey post-hoc test for comparison between groups ### P<0.001, ## P<0.01, #P<0.05 vs. CON; $$P<0.01 Tempol vs. baseline; &&& P<0.001 PEG-catalase vs. baseline; § P<0.05 vehicle vs. baseline.