In:
Physiological Reports, Wiley, Vol. 5, No. 6 ( 2017-03)
Abstract:
Under high sodium intake renal dopamine ( DA ) increases while NOS I expression in macula densa cells ( MD ) decreases. To explore whether renal DA and NOS I, linked to natriuresis and to the stability of the tubuloglomerular feedback, respectively, act in concert to regulate renal plasma flow ( RPF ) and glomerular filtration rate ( GFR ). Male Wistar rats were studied under a normal sodium intake ( NS , NaCl 0.24%) or a high sodium intake ( HS , NaCl 1% in drinking water) during the 5 days of the study. For the last two days, the specific D 1 ‐like receptor antagonist SCH 23390 (1 mg kg bwt −1 day −1 , sc) or a vehicle was administered. HS intake increased natriuresis, diuresis, and urinary DA while it decreased cortical NOS I expression ( P 〈 0.05 vs. NS ), Nicotinamide adenine dinucleotide phosphate diaphorase ( NADPH ‐d) activity in MD ( P 〈 0.001 vs. NS ) and cortical nitrates+nitrites ( NO x) production ( NS 2.04 ± 0.22 vs. HS 1.28 ± 0.10 nmol mg protein −1 , P 〈 0.01). Treatment with SCH 23390 to rats on HS sharply decreased hydroelectrolyte excretion ( P 〈 0.001 vs. HS ) while NOS I expression, NADPH ‐d activity and NO x production increased ( P 〈 0.05 vs. HS for NOS I and P 〈 0.001 vs. HS for NADPH ‐d and NO x). SCH 23390 increased RPF and GFR in HS rats ( P 〈 0.01 HS + SCH vs. HS ). It did not cause variations in NS rats. Results indicate that when NS intake is shifted to a prolonged high sodium intake, renal DA through the D 1 R, and NOS I in MD cells act in concert to regulate RPF and GFR to stabilize the delivery of NaCl to the distal nephron.
Type of Medium:
Online Resource
ISSN:
2051-817X
,
2051-817X
Language:
English
Publisher:
Wiley
Publication Date:
2017
detail.hit.zdb_id:
2724325-4
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