Table 1.

Na⁺ handling in nephron segments (in mmol/min)

Segment	Inflow	Reabsorption	Outflow	Fractional Na+ Reabsorption
Baseline
PT	9.63	5.79	3.83	0.60
Loop	3.83	2.84	0.99	0.74
DT	0.99	0.72	0.27	0.73
CD	0.27	0.20	0.07	0.74
BA
PT	7.58	3.70	3.88	0.49
Loop	3.88	2.95	0.93	0.76
DT	0.93	0.71	0.22	0.76
CD	0.22	0.15	0.07	0.69
BA + renal clamp
PT	8.60	5.21	3.40	0.61
Loop	3.40	2.54	0.86	0.75
DT	0.86	0.67	0.18	0.79
CD	0.18	0.12	0.07	0.63
BA + cardiac clamp
PT	7.91	3.84	4.07	0.49
Loop	4.07	3.07	0.99	0.75
DT	1.00	0.72	0.28	0.72
CD	0.28	0.21	0.07	0.75
BA + renal + cardiac clamp
PT	9.19	5.51	3.69	0.60
Loop	3.69	2.74	0.94	0.74
DT	0.94	0.69	0.25	0.74
CD	0.25	0.18	0.07	0.72

BA, baroreflex activation; PT, proximal tubule; Loop, loop of Henle; DT, distal tubule; CD, collecting duct.