MTOR and cardiac hypertrophy: The major findings of this study were as follows: (i) LPA aggravated cardiac dysfunction and promoted cardiac hypertrophy following MI; (ii) LPA down-regulated autophagy in vivo and in vitro; (iii) autophagy was involved in LPA-induced H9C2 cardiomyoblast hypertrophy; and (iv) LPA down-regulated autophagy through activation of the LPA3 receptor and mTOR signaling pathway.