Ghrelin suppresses cardiac fibrosis of post-myocardial infarction heart failure rats by adjusting the activin A-follistatin imbalance.

•Ghrelin relieves rat heart failure following myocardial infarction.•Ghrelin alleviates left ventricular reconstruction by inhibiting myocardial fibrosis.•Ghrelin restrains myocardial fibrosis by regulating Activin A/Follistatin imbalance.•Activin A promotes cardiac fibroblast proliferation and collagen synthesis.