The effect of losartan on differential reflex control of sympathetic nerve activity in chronic kidney disease.
J Hypertens
; 33(6): 1249-60, 2015 Jun.
Article
em En
| MEDLINE
| ID: mdl-25764047
ABSTRACT
BACKGROUND:
The effect of angiotensin II type I receptor (AT1R) inhibition on the pattern of reflex sympathetic nerve activity (SNA) to multiple target organs in the Lewis polycystic kidney (LPK) rat model of chronic kidney disease was determined.METHODS:
Mean arterial pressure (MAP), splanchnic SNA (sSNA), renal SNA (rSNA) and lumbar SNA (lSNA) were recorded in urethane-anaesthetized LPK and Lewis controls (total nâ=â39). Baroreflex, peripheral and central chemoreflex, and somatosensory reflex control of SNA (evoked by phenylephrine/sodium nitroprusside infusion, 10% O2 in N2 or 100% N2 ventilation, 5% CO2 ventilation and sciatic nerve stimulation, respectively) were determined before and after administration of losartan (AT1R antagonist 3âmg/kg, intravenous).RESULTS:
Baseline MAP was higher in LPK rats and baroreflex control of sSNA and rSNA, but not lSNA, was reduced. Losartan reduced MAP in both strains and selectively improved baroreflex gain for sSNA (-1.2â±â0.1 vs. -0.7â±â0.07â%/mmHg; Pâ<â0.05) in LPK. The peripheral and central chemoreflex increased MAP and all SNA in Lewis controls, but reduced or had no effect on these parameters, respectively, in LPK. The SNA response to somatosensory stimulation was biphasic, with latency to second peak less in LPK. Losartan ameliorated the depressor and sympathoinhibitory responses to peripheral chemoreflex stimulation in the LPK, but did not alter the central chemoreflex or somatosympathetic responses.CONCLUSION:
Inhibition of the AT1R selectively improved baroreflex control of sSNA and peripheral chemoreflex control of all three sympathetic nerve outflows in the LPK rat, suggesting these anomalies in reflex function are driven in part by angiotensin II.
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
1_ASSA2030
Base de dados:
MEDLINE
Assunto principal:
Sistema Nervoso Simpático
/
Barorreflexo
/
Losartan
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Bloqueadores do Receptor Tipo 1 de Angiotensina II
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Insuficiência Renal Crônica
Limite:
Animals
Idioma:
En
Revista:
J Hypertens
Ano de publicação:
2015
Tipo de documento:
Article