A. Schematic representation of heat shock treatments (arrows) and cardiac cryoinjury. Immunostaining of sections of cryoinjured hearts of Tg(0.8flt1:RFP) (Ctrl) (A’) and Tg(hsp70l:emilin2a); Tg(−0.8flt1:RFP)
(A”) sibling zebrafish at 96 hpci; sections stained for RFP (coronaries, magenta), PCNA (proliferation marker, green), and DNA (DAPI, blue). Arrowheads point to PCNA+ cECs. B. Percentage of PCNA+ cECs in the border zone of Tg(−0.8flt1RFP) (Ctrl) (n=4) and Tg(hsp70l:emilin2a); Tg(−0.8flt1:RFP) ventricles (n=4) at 96 hpci. C. Schematic representation of heat shock treatments (arrows) and cardiac cryoinjury. Immunostaining of sections of cryoinjured hearts of non-transgenic sibling (Ctrl) (C’) and Tg(hsp70l:emilin2a)
(C”) zebrafish at 7 dpci; sections stained for MEF2 (CMs, magenta), PCNA (proliferation marker, green), and DNA (DAPI, blue). Arrowheads point to PCNA+ CMs. D. Percentage of PCNA+ CMs in the border zone of non-transgenic sibling (Ctrl) (n=6) and Tg(hsp70l:emilin2a) (n=6) ventricles at 7 dpci. E. Schematic representation of heat shock treatments (arrows) and cardiac cryoinjury. AFOG staining of sections of non-transgenic sibling (Ctrl) (E’) and Tg(hsp70l:emilin2a)
(E”) ventricles at 30 dpci. Orange, Muscle; red, Fibrin; blue, Collagen. F. Percentage of scar area relative to ventricular area in non-transgenic sibling (Ctrl) (n=5) and Tg(hsp70l:emilin2a) (n=6) ventricles at 30 dpci. G. Schematic representation of Ethanol (EtOH) or 4-hydroxytamoxifen (4-OHT) injections followed by cardiac cryoinjury and heat shock treatments (arrows). Immunostaining of sections of cryoinjured hearts of Tg(hsp70l:sflt4); TgBAC(tcf21:CreERT2); Tg(hsp70l:LCL-emilin2a-p2A-mCherry) zebrafish injected with EtOH (G’) or 4-OHT (G”) at 96 hpci; sections stained for Fli1a (endothelial cells, magenta), PCNA (proliferation marker, white), and DNA (DAPI, blue). Arrowheads point to PCNA+ cECs. H. Percentage of PCNA+ cECs in the border zone of Tg(hsp70l:sflt4); TgBAC(tcf21:CreERT2); Tg(hsp70l:LCL-emilin2a-mCherry) at 96 hpci injected with EtOH (n=6) or 4-OHT (n=4). I. Schematic representation of Ethanol (EtOH) or 4-hydroxytamoxifen (4-OHT) injections followed by cardiac cryoinjury and heat shock treatments (arrows). AFOG staining of sections of cryoinjured hearts of Tg(hsp70l:sflt4); TgBAC(tcf21:CreERT2); Tg(hsp70l:LCL-emilin2a-p2A-mCherry) zebrafish injected with EtOH (I’) or 4-OHT (I”) at 30 dpci. Orange, Muscle; red, Fibrin; blue, Collagen. J. Percentage of scar area relative to ventricular area in Tg(hsp70l:sflt4); TgBAC(tcf21:CreERT2); Tg(hsp70l:LCL-emilin2a-mCherry) at 30 dpci injected with EtOH (n=4) or 4-OHT (n=4). White (A,C,G), and Black (E,I) dotted lines delineate the injured tissue. Statistical test: Student’s t-test (B,D,F,H,J). Scale Bars: 100 μm (A,C,G), 200 μm (E,I).