title: Dipyridamole-induced C-type natriuretic peptide mRNA overexpression in a minipig model of pacing-induced left ventricular dysfunction.
abstract: Dipyridamole (DP) restores ischemic tissue blood flow stimulating angiogenesis in eNOS-dependent pathways. C-type natriuretic peptide (CNP) is expected to mimic the migration-stimulatory effect of NO via a cGMP-dependent mechanism. Aim of this study was to assess the role of concomitant treatment with DP on CNP levels in blood and myocardial tissue of minipigs with left ventricular dysfunction (LVD) induced by pacing at 200bpm in the right ventricular apex. Minipigs with DP therapy (DP+, n=4) or placebo (DP-, n=4) and controls (C-SHAM, n=4) underwent 2D-EchoDoppler examination and blood collection before and after 4 weeks of pacing, when cardiac tissue was collected. Histological/immunohistochemical analyses were performed. CNP levels were determined by radioimmunoassay; cardiac CNP, BNP, natriuretic receptors expression by Real-Time PCR. After pacing, cardiac parameters resulted less impaired in DP+ compared to DP-. Histological sections presented normal morphology while the arteriolar density resulted: C-SHAM: 9.0±1.2; DP-: 4.9±0.3; DP+: 6.5±0.6number/mm(2); C-SHAM vs DP- and DP+ p=0.004, p=0.04, respectively. CNP mRNA resulted lower in DP- compared to C-SHAM and DP+ as well as NPR-B (p=0.011, DP- vs DP+). Both NPR-A/NPR-C mRNA expressions were significantly (p<0.001) lower both in DP- and DP+ compared to C-SHAM. BNP mRNA was higher in LVD. CNP plasma levels showed a similar trend with respect to gene expression (C-SHAM: 30.5±15; DP-: 18.6±5.5; DP+: 21.2±4.7pg/ml). These data suggest that DP may serve as a preconditioning agent to increase the protective CNP-mediated endocrine response in LVD. This response, mediated by its specific receptor NPR-B, may offer new insights into molecular targets for treatment of LVD.
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Cabiati
authors.affiliation: Fondazione Toscana G. Monasterio, Pisa, Italy.
authors.forename: S
authors.initials: S
authors.lastname: Burchielli
authors.affiliation: Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: M
authors.initials: M
authors.lastname: Matteucci
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy; Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Svezia
authors.affiliation: Fondazione Toscana G. Monasterio, Pisa, Italy.
authors.forename: L
authors.initials: L
authors.lastname: Panchetti
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Caselli
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy.
authors.forename: T
authors.initials: T
authors.lastname: Prescimone
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy.
authors.forename: M A
authors.initials: MA
authors.lastname: Morales
authors.affiliation: CNR Institute of Clinical Physiology, CNR, Italy. Electronic address: delry@ifc.cnr.it.
authors.forename: S
authors.initials: S
authors.lastname: Del Ry
mesh_terms: D000818:Animals; D002304:Cardiac Pacing, Artificial; D004176:Dipyridamole / Q000494:pharmacology* / Q000627:therapeutic use; D004195:Disease Models, Animal; D006321:Heart / Q000187:drug effects; D020098:Natriuretic Peptide, C-Type / Q000235:genetics / Q000378:metabolism*; D020011:Protective Agents / Q000494:pharmacology* / Q000627:therapeutic use; D012333:RNA, Messenger / Q000378:metabolism; D013552:Swine; D013556:Swine, Miniature; D015854:Up-Regulation; D018487:Ventricular Dysfunction, Left / Q000188:drug therapy / Q000209:etiology / Q000235:genetics / Q000378:metabolism*
chemical_list: D020011:Protective Agents; D012333:RNA, Messenger; D020098:Natriuretic Peptide, C-Type; D004176:Dipyridamole
keywords: C-type natriuretic peptide; Dipyridamole; Left ventricular dysfunction; RIA; mRNA