Lisinopril indifferently improves heart rate variability during day and night periods in spontaneously hypertensive rats

S. Albarwani, S. Al-Siyabi, M. O. Tanira

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7 Citations (Scopus)


The aim of this work was to investigate the effect of 10 weeks of lisinopril treatment to spontaneously hypertensive rats (SHRs) on day/night variations of blood pressure, heart rate and autonomic cardio-regulation parameters. Male SHR with surgically implanted radio-telemetry implant that provided direct measurements of arterial pressure and electrocardiogram wave were used. Animals were allocated to two groups (n=5 each). The first group was treated with lisinopril (20 mg/kg by gavage) daily for 10 weeks (treated group); whereas the second was gavaged daily with tap water (untreated group). Arterial blood pressure, ECG and other telemetry parameters were recorded at the start and at the end of 10-week treatment. Collected data were analyzed using specialized software and were statistically tested. In addition to the expected lowering of blood pressure, spectral analysis of R-R intervals revealed that lisinopril treatment for 10 weeks significantly caused 2-3 fold increase in heart rate variability (HRV) during both active and inactive periods. However, R-R interval durations demonstrated variable distribution patterns during those periods. The cause of observed distribution pattern of R-R intervals during active and inactive periods may be of significance to better understand HRV changes and warrants further investigations.

Original languageEnglish
Pages (from-to)237-245
Number of pages9
JournalPhysiological Research
Issue number3
Publication statusPublished - 2013



  • ACE-inhibitor
  • Circadian rhythm
  • Heart rate variability
  • Hypertension
  • Lisinopril
  • SHR
  • Telemetry

ASJC Scopus subject areas

  • Physiology

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