Chronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats

dc.creatorSilva, Fernanda C.
dc.creatorPaiva, Franciny A.
dc.creatorMueller-Ribeiro, Flavia C.
dc.creatorCaldeira, Henrique M. A.
dc.creatorFontes, Marco A. P.
dc.creatorde Menezes, Rodrigo C. A.
dc.creatorCasali, Karina R. [UNIFESP]
dc.creatorFortes, Glaucia H.
dc.creatorTobaldini, Eleonora
dc.creatorSolbiati, Monica
dc.creatorMontano, Nicola
dc.creatorDias Da Silva, Valdo J.
dc.creatorChianca, Deoclecio A., Jr.
dc.date.accessioned2020-08-14T13:44:11Z
dc.date.accessioned2023-09-04T18:40:46Z
dc.date.available2020-08-14T13:44:11Z
dc.date.available2023-09-04T18:40:46Z
dc.date.created2020-08-14T13:44:11Z
dc.date.issued2016
dc.identifierFrontiers In Physiology. Lausanne, v. 7, p. -, 2016.
dc.identifier1664-042X
dc.identifierhttps://repositorio.unifesp.br/handle/11600/57530
dc.identifierWOS000380217900002.pdf
dc.identifier10.3389/fphys.2016.00305
dc.identifierWOS:000380217900002
dc.identifier.urihttps://repositorioslatinoamericanos.uchile.cl/handle/2250/8617682
dc.description.abstractA low resting heart rate (HR) would be of great benefit in cardiovascular diseases. Ivabradine a novel selective inhibitor of hyperpolarization-activated cyclic nucleotide gated (HCN) channels- has emerged as a promising HR lowering drug. Its effects on the autonomic HR control are little known. This study assessed the effects of chronic treatment with ivabradine on the modulatory, reflex and tonic cardiovascular autonomic control and on the renal sympathetic nerve activity (RSNA). Male Wistar rats were divided in 2 groups, receiving intraperitoneal injections of vehicle (VEH) or ivabradine (IVA) during 7 or 8 consecutive days. Rats were submitted to vessels cannulation to perform arterial blood pressure (AP) and HR recordings in freely moving rats. Time series of resting pulse interval and systolic AP were used to measure cardiovascular variability parameters. We also assessed the baroreflex, chemoreflex and the Bezold-Jarish reflex sensitivities. To better evaluate the effects of ivabradine on the autonomic control of the heart, we performed sympathetic and vagal autonomic blockade. As expected, ivabradine treated rats showed a lower resting (VEH: 362 +/- 16 bpm vs. IVA: 260 +/- 14 bpm, p = 0.0005) and intrinsic HR (VEH: 369 +/- 9 bpm vs. IVA: 326 +/- 11 bpm, p = 0.0146). However, the chronic treatment with ivabradine did not change normalized HR spectral parameters LF (nu) (VEH: 24.2 +/- 4.6 vs. IVA: 29.8 +/- 6.4
dc.description.abstractp > 0.05)
dc.description.abstractHF (nu) (VEH: 75.1 +/- 3.7 vs. IVA: 69.2 +/- 5.8
dc.description.abstractp > 0.05), any cardiovascular reflexes, neither the tonic autonomic control of the HR (tonic sympathovagal index
dc.description.abstractVEH: 0.91 +/- 0.02 vs. IVA: 0.88 +/- 0.03, p = 0.3494). We performed the AP, HR and RSNA recordings in urethane-anesthetized rats. The chronic treatment with ivabradine reduced the resting HR (VEH: 364 +/- 12 bpm vs. IVA: 207 +/- 11 bpm, p < 0.0001), without affecting RSNA (VEH: 117 +/- 16 vs. IVA: 120 +/- 9 spikes/s, p = 0.9100) and mean arterial pressure (VEH: 70 +/- 4 vs. IVA: 77 +/- 6 mmHg, p = 0.3293). Our results suggest that, in health rats, the long-term treatment with ivabradine directly reduces the HR without changing the RSNA modulation and the reflex and tonic autonomic control of the heart.
dc.languageeng
dc.publisherFrontiers Media Sa
dc.relationFrontiers In Physiology
dc.rightsAcesso aberto
dc.subjectivabradine
dc.subjectHCN channels
dc.subjectrenal sympathetic nerve activity
dc.subjectcardiovascular reflexes
dc.subjecttonic control
dc.subjectvagal activity
dc.subjectsympathetic activity
dc.titleChronic Treatment with Ivabradine Does Not Affect Cardiovascular Autonomic Control in Rats
dc.typeArtigo


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