Macrophage migration inhibitory factor in the nucleus of solitary tract decreases blood pressure in SHRs

Author(s)

Freiria-Oliveira, Andre Henrique ^{[1, 2, 3]} ; Blanch, Graziela Torres ^{[1, 2, 3]} ; Li, Hongwei ^[4] ; Colombari, Eduardo ^[3] ; Almeida Colombari, Debora Simoes ^[3] ; Sumners, Colin ^{[1, 2]}

Affiliation

^[1] Univ Florida, Coll Med, Dept Physiol & Funct Genom, Gainesville, FL 32610 - USA

^[2] Univ Florida, Coll Med, McKnight Brain Inst, Gainesville, FL 32610 - USA

^[3] Sao Paulo State Univ, Sch Dent, Dept Physiol & Pathol, Araraquara, SP - Brazil

^[4] So Med Univ, Sch Biotechnol, Guangzhou, Guangdong - Peoples R China

• Document type: Journal article
• Source: Cardiovascular Research; v. 97, n. 1, p. 153-160, JAN 1 2013.
• Web of Science Citations: 12

Abstract

The macrophage migration inhibitory factor (MIF) is an intracellular inhibitor of the central nervous system actions of angiotensin II on blood pressure. Considering that angiotensin II actions at the nucleus of the solitary tract are important for the maintenance of hypertension in spontaneously hypertensive rats (SHRs), we tested if increased MIF expression in the nucleus of the solitary tract of SHR alters the baseline high blood pressure in these rats. Eight-week-old SHRs or normotensive rats were microinjected with the vector AAV2-CBA-MIF into the nucleus of the solitary tract, resulting in MIF expression predominantly in neurons. Rats also underwent recordings of the mean arterial blood pressure (MAP) and heart rate (via telemetry devices implanted in the abdominal aorta), cardiac- and baroreflex function. Injections of AAV2-CBA-MIF into the nucleus of the solitary tract of SHRs produced significant decreases in the MAP, ranging from 10 to 20 mmHg, compared with age-matched SHRs that had received identical microinjections of the control vector AAV2-CBA-eGFP. This lowered MAP in SHRs was maintained through the end of the experiment at 31 days, and was associated with an improvement in baroreflex function to values observed in normotensive rats. In contrast to SHRs, similar increased MIF expression in the nucleus of the solitary tract of normotensive rats produced no changes in baseline MAP and baroreflex function. These results indicate that an increased expression of MIF within the nucleus of the solitary tract neurons of SHRs lowers blood pressure and restores baroreflex function. (AU)

• FAPESP's process: 10/09250-1 - Migration inhibitor factor and reactive oxigen species within nucleus tractus solitarius: role on cardiovascular control and hydroelectrolytic balance in SHR
• Grantee: André Henrique Freiria de Oliveira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 11/50770-1 - Neural mechanisms involved of hydroelectrolytic balance and cardiorespiratory control
• Grantee: José Vanderlei Menani
• Support Opportunities: Research Projects - Thematic Grants