Table 1.

Effect of EIPA on water and ion transport in perfused loops of Henle

	n	Perfusion rate (nl min−1)	(C/P)In	Jv (nl min−1)	Collectate [Na7plus;] (mmol l−1)	JNa (pmol min−1)	Collectate [K+] (mmol l−1)	JK (pmol min−1)
Standard perfusate
Control	34	19.7 ± 0.3	1.69 ± 0.06	7.7 ± 0.4	69 ± 3	1971 ± 71	2.5 ± 0.2	47 ± 2
EIPA	28	19.6 ± 0.3	1.61 ± 0.05	7.4 ± 0.4	76 ± 4	1851 ± 90	2.6 ± 0.1	44 ± 2
Low-Na+ perfusate-
Control	46	19.9 ± 0.2	1.08 ± 0.01	1.5 ± 0.1	73 ± 2	828 ± 41	2.4 ± 0.1	28 ± 2
EIPA	40	20.2 ± 0.2	1.08 ± 0.01	1.4 ± 0.2	80 ± 2 *	726 ± 37 *	2.5 ± 0.1	27 ± 2
Low-Na+ perfusate + bumetanide-
Control	32	19.8 ± 0.2	1.02 ± 0.01	0.4 ± 0.2	108 ± 1	86 ± 27	4.7 ± 0.2	−20 ± 3
EIPA	30	20.3 ± 0.4	1.00 ± 0.01	0.1 ± 0.2	112 ± 2	−24 ± 18 *	4.5 ± 0.1	−18 ± 2
Low-Na+, high-bicarbonate perfusate-
Control	15	19.9 ± 0.3	1.04 ± 0.02	0.8 ± 0.2	68 ± 2	887 ± 42	2.6 ± 0.2	24 ± 3
EIPA	16	19.8 ± 0.3	1.06 ± 0.01	1.1 ± 0.2	80 ± 1†	689 ± 24†	2.6 ± 0.1	25 ± 3

Values are means ±s.e.m.n, number of tubules perfused; (C/P)_In, collectate/perfusate [¹⁴C] inulin concentration ratio; J_v, net water flux; J_Na, net sodium flux;J_K, net potassium flux; EIPA, ethyl isopropyl amiloride.

^*P < 0.05

^†P < 0.001 compared with corresponding value in the absence of EIPA.