Journal article
Brain perivascular macrophages and the sympathetic response to inflammation in rats after myocardial infarction
Hypertension (Dallas, Tex. 1979), Vol.55(3), pp.652-659
03/2010
DOI: 10.1161/HYPERTENSIONAHA.109.142836
PMCID: PMC2890291
PMID: 20142564
Abstract
Inflammation is associated with increased sympathetic drive in cardiovascular diseases. Blood-borne proinflammatory cytokines, markers of inflammation, induce cyclooxygenase 2 (COX-2) activity in perivascular macrophages of the blood-brain barrier. COX-2 generates prostaglandin E(2), which may enter the brain and increase sympathetic nerve activity. We examined the contribution of this mechanism to augmented sympathetic drive in rats after myocardial infarction (MI). Approximately 24 hours after acute MI, rats received an intracerebroventricular injection (1 microL/min over 40 minutes) of clodronate liposomes (MI+CLOD) to eliminate brain perivascular macrophages, liposomes alone, or artificial cerebrospinal fluid. A week later, COX-2 immunoreactivity in perivascular macrophages and COX-2 mRNA and protein had increased in hypothalamic paraventricular nucleus of MI rats treated with artificial cerebrospinal fluid or liposomes alone compared with sham-operated rats. In MI+CLOD rats, neither perivascular macrophages nor COX-2 immunoreactivity was seen in the paraventricular nucleus, and COX-2 mRNA and protein levels were similar to those in sham-operated rats. Prostaglandin E(2) in cerebrospinal fluid, paraventricular nucleus neuronal excitation, and plasma norepinephrine were less in MI+CLOD rats than in MI rats treated with artificial cerebrospinal fluid or liposomes alone but more than in sham-operated rats. Intracerebroventricular CLOD had no effect on interleukin 1beta and tumor necrosis factor-alpha mRNA and protein in the paraventricular nucleus or plasma interleukin-1beta and tumor necrosis factor-alpha, which were increased in MI compared with sham-operated rats. In normal rats, pretreatment with intracerebroventricular CLOD reduced (P<0.05) the renal sympathetic, blood pressure, and heart rate responses to intracarotid artery injection of tumor necrosis factor-alpha (0.5 microg/kg); intracerebroventricular liposomes had no effect. The results suggest that proinflammatory cytokines stimulate sympathetic excitation after MI by inducing COX-2 activity and prostaglandin E(2) production in perivascular macrophages of the blood-brain barrier.
Details
- Title: Subtitle
- Brain perivascular macrophages and the sympathetic response to inflammation in rats after myocardial infarction
- Creators
- Yang Yu - Department of Veterans' Affairs Medical Center, Iowa City, Iowa, USAZhi-Hua ZhangShun-Guang WeiJordi SerratsRobert M WeissRobert B Felder
- Resource Type
- Journal article
- Publication Details
- Hypertension (Dallas, Tex. 1979), Vol.55(3), pp.652-659
- Publisher
- United States
- DOI
- 10.1161/HYPERTENSIONAHA.109.142836
- PMID
- 20142564
- PMCID
- PMC2890291
- ISSN
- 0194-911X
- eISSN
- 1524-4563
- Grant note
- R01 HL073986-05A2 / NHLBI NIH HHS R01HL073986 / NHLBI NIH HHS R01 HL073986 / NHLBI NIH HHS
- Language
- English
- Date published
- 03/2010
- Academic Unit
- Iowa Neuroscience Institute; Cardiovascular Medicine; Internal Medicine
- Record Identifier
- 9984065385202771
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