title: Intramyocardial delivery of basic fibroblast growth factor-impregnated gelatin hydrogel microspheres enhances collateral circulation to infarcted canine myocardium.
abstract: The present study examined whether basic fibroblast growth factor (bFGF)-impregnated acidic gelatin hydrogel microspheres (AGHM) would enhance collateral development to the infarct area in dogs with coronary occlusion. Studies were conducted in 28 dogs with a 2-week occlusion of the proximal left anterior descending coronary artery (LAD). The dogs were divided into 3 groups according to treatment: Group A treated with bFGF-impregnated AGHM in the infarct area; Group B with free-form bFGF; Group C with AGHM alone. Coronary angiography (n=15; Group A, 7 dogs; Group B, 5 dogs; Group C, 3 dogs) and a regional myocardial blood flow study (n=13; Group A, 6 dogs; Group B, 4 dogs; Group C, 3 dogs) were repeated at a 2-week interval. Coronary angiography revealed that in Group A, antegrade flow in the LAD distal to the occlusion, which was assessed by Thrombolysis in Myocardial Infarction (TIMI) grade, was significantly increased after treatment. In contrast, in Groups B and C, the treatment did not change the flow grade in the LAD. In Group A, the regional myocardial blood flow in the collateral dependent area was significantly increased after treatment, and the regional myocardial blood flow reserve after adenosine injection was also significantly increased. These measurements remained after treatment in Groups B and C. The immunohistochemical study with factor VIII-related antigen revealed an increase of vascular density in the ischemic region in Group A. Intramyocardial delivery of bFGF-impregnated AGHM, but not free-form bFGF, improves the collateral circulation to the infarct area of a coronary occlusion in dogs.
authors.affiliation: Second Department of Internal Medicine, Hirosaki University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamamoto
authors.forename: N
authors.initials: N
authors.lastname: Suto
authors.forename: T
authors.initials: T
authors.lastname: Okubo
authors.forename: A
authors.initials: A
authors.lastname: Mikuniya
authors.forename: H
authors.initials: H
authors.lastname: Hanada
authors.forename: S
authors.initials: S
authors.lastname: Yagihashi
authors.forename: M
authors.initials: M
authors.lastname: Fujita
authors.forename: K
authors.initials: K
authors.lastname: Okumura
mesh_terms: D000818:Animals; D003097:Collateral Circulation / Q000187:drug effects*; D004285:Dogs; D016503:Drug Delivery Systems; D016222:Fibroblast Growth Factor 2 / Q000008:administration & dosage* / Q000627:therapeutic use; D005780:Gelatin; D008863:Microspheres; D009203:Myocardial Infarction / Q000188:drug therapy* / Q000473:pathology
chemical_list: D016222:Fibroblast Growth Factor 2; D005780:Gelatin