Abstract
Background: Healing after myocardial infarction is characterized by the presence of macrophages in the infarcted area. Since augmented monocyte influx has been implicated as a potential mechanism for improved healing after reperfusion, we wished to study the induction of monocyte chemoattractant protein-1 (MCP-1) during reperfusion. Methods and Results: The cDNA for MCP-1 was cloned from a canine jugular vein endothelial cell (CJVEC) library and exhibited 78% identity with the deduced amino acid sequence of human MCP-1. Samples of myocardium were taken from control and ischemic segments after 1 hour of ischemia and various times of reperfusion: total RNA was isolated from myocardial samples and probed with a cDNA probe for canine MCP-1. Induction of MCP-1 mRNA occurred only in previously ischemic segments within the first hour of reperfusion, peaked at 3 hours, and persisted throughout the first 2 days of reperfusion. In the absence of reperfusion, no significant MCP-1 induction was seen. Both ischemic (but not preischemic) cardiac lymph and human recombinant TNF-α induced MCP-1 in CJVECs. MCP-1 was identified by immunostaining on infiltrating cells and venular (but not arterial) endothelium by 3 hours. In contrast, in situ hybridization showed MCP-1 mRNA to be confined to the endothelium of small veins (venules) 10 to 70 μm in diameter. Conclusions: MCP-1 mRNA is induced in the endothelium of a specific class of small veins immediately after reperfusion. MCP-1 induction is confined to the previously ischemic area that has been reperfused. We suggest a significant role for MCP-1 in monocyte trafficking in the reperfused myocardium.
Original language | English (US) |
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Pages (from-to) | 693-700 |
Number of pages | 8 |
Journal | Circulation |
Volume | 95 |
Issue number | 3 |
DOIs | |
State | Published - 1997 |
Externally published | Yes |
Keywords
- cytokines
- myocardial infarction
- proteins, monocyte chemoattractant
- reperfusion
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine
- Physiology (medical)