Analysis of the respiratory component of heart rate variability in the Cururu toad Rhinella schneideri

Author(s)

Zena, Lucas A. ^{[1, 2]} ; Leite, Cleo A. C. ^{[1, 3]} ; Longhini, Leonardo S. ^{[1, 2]} ; Dias, Daniel P. M. ^[4] ; da Silva, Glauber S. F. ^{[1, 2]} ; Hartzler, Lynn K. ^[5] ; Gargaglioni, Luciane H. ^{[1, 2]} ; Bicego, Kenia C. ^{[1, 2]}

Affiliation

^[1] Natl Inst Sci & Technol Comparat Physiol INCT Fis, Jaboticabal, SP - Brazil

^[2] Sao Paulo State Univ, Coll Agr & Vet Sci, Dept Anim Morphol & Physiol, BR-14884900 Jaboticabal, SP - Brazil

^[3] Univ Fed Sao Carlos, Dept Physiol Sci, Sao Carlos, SP - Brazil

^[4] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Physiol, Ribeirao Preto, SP - Brazil

^[5] Wright State Univ, Dept Biol Sci, Dayton, OH 45435 - USA

• Document type: Journal article
• Source: SCIENTIFIC REPORTS; v. 7, NOV 23 2017.
• Web of Science Citations: 4

Abstract

Beat-to-beat variation in heart rate (fH) has been used as a tool for elucidating the balance between sympathetic and parasympathetic modulation of the heart. A portion of the temporal changes in fH is evidenced by a respiratory influence (cardiorespiratory interaction) on heart rate variability (HRV) with heartbeats increasing and decreasing within a respiratory cycle. Nevertheless, little is known about respiratory effects on HRV in lower vertebrates. By using frequency domain analysis, we provide the first evidence of a ventilatory component in HRV similar to mammalian respiratory sinus arrhythmia in an amphibian, the toad Rhinella schneideri. Increases in the heartbeats arose synchronously with each lung inflation cycle, an intermittent breathing pattern comprised of a series of successive lung inflations. A well-marked peak in the HRV signal matching lung inflation cycle was verified in toads whenever lung inflation cycles exhibit a regular rhythm. The cardiac beat-to-beat variation evoked at the moment of lung inflation accounts for both vagal and sympathetic influences. This cardiorespiratory interaction may arise from interactions between central and peripheral feedback mechanisms governing cardiorespiratory control and may underlie important cardiorespiratory adjustments for gas exchange improvement especially under extreme conditions like low oxygen availability. (AU)

• FAPESP's process: 08/57712-4 - The National Institute of Comparative Physiological Research
• Grantee: Augusto Shinya Abe
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 12/17379-0 - Arterial baroreflex function in toads Rhinella schneideri: temperature effect, hydration state and role of renin-angiotensin system
• Grantee: Lucas Aparecido Zena
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 14/12190-1 - Serotonin and respiratory control in vertebrates
• Grantee: Glauber dos Santos Ferreira da Silva
• Support Opportunities: Scholarships in Brazil - Young Researchers
• FAPESP's process: 13/17606-9 - Serotonin and respiratory control in vertebrates
• Grantee: Glauber dos Santos Ferreira da Silva
• Support Opportunities: Research Grants - Young Investigators Grants