The Bezold-Jarisch Reflex and The Inflammatory Response Modulation in Unanesthetized Endotoxemic Rats

Author(s)

Brognara, Fernanda ^[1] ; Castania, Jaci Airton ^[1] ; Ribeiro, Aline Barbosa ^[1] ; Santos-Junior, Nilton Nascimento ^[2] ; Salgado, Helio Cesar ^[1]

Affiliation

^[1] Univ Sao Paulo, Ribeirao Preto Med Sch, Dept Physiol, Ribeirao Preto - Brazil

^[2] Minas Gerais State Univ, Passos - Brazil

• Document type: Journal article
• Source: FRONTIERS IN PHYSIOLOGY; v. 12, SEP 20 2021.
• Web of Science Citations: 0

Abstract

Evidence indicates that the activation of the parasympathetic branch of the autonomic nervous system may be effective in treating inflammatory diseases. Previously, we have described that baroreflex activation displays anti-inflammatory properties. Analogous to the baroreflex, the Bezold-Jarisch reflex also promotes parasympathetic activation with simultaneous inhibition of the sympathetic system. Thus, the present study aimed to evaluate whether the activation of the Bezold-Jarisch reflex would also have the ability to reduce inflammation in unanesthetized rats. We used lipopolysaccharide (LPS) injection (5mg/kg, i.p.) to induce systemic inflammation in male Wistar Hannover rats and phenylbiguanide (PBG) administration (5 mu g/kg, i.v.) to activate the Bezold-Jarisch reflex. Spleen, heart, hypothalamus, and blood samples were collected to determine the levels of cytokines. Compared to baseline, PBG reduced the arterial pressure (115 +/- 2 vs. 88 +/- 5mmHg) and heart rate (380 +/- 7 vs. 114 +/- 26bpm), immediately after its administration, confirming the activation of the parasympathetic system and inhibition of the sympathetic system. From the immunological point of view, the activation of the Bezold-Jarisch reflex decreased the plasma levels of TNF (LPS: 775 +/- 209 vs. PBG + LPS: 248 +/- 30pg/ml) and IL-6 levels in the spleen (LPS: 39 +/- 6 vs. PBG + LPS: 24 +/- 4pg/mg of tissue). However, it did not change the other cytokines in the plasma or the other tissues evaluated. These findings confirm that the activation of the Bezold-Jarisch reflex can modulate inflammation and support the understanding that the cardiovascular reflexes regulate the immune system.</p> (AU)

• FAPESP's process: 13/20549-7 - New insights in cardiovascular regulation under physiological and pathophysiological condition
• Grantee: Helio Cesar Salgado
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 20/06043-7 - Autonomic (sympathetic and parasympathetic) modulation of cardiovascular and inflammatory responses under physiopathological clinical and experimental conditions
• Grantee: Helio Cesar Salgado
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 18/10455-9 - Role of electrical activaton of the carotid sinus nerve, in conscious rats, in the attenuation of local and systemic inflammatory response elicited by periodontitis.
• Grantee: Aline Barbosa Ribeiro
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 18/20939-3 - New insights in Cardiovascular Regulation under Physiological and Pathophysiological Condition.
• Grantee: Nilton Nascimento dos Santos Júnior
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 17/05163-6 - Role of the parasympathetic and sympathetic autonomic nervous system in the modulation of sepsis in unanesthetized rats
• Grantee: Fernanda Brognara Penteado Dias
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)