TECHNICAL FIELD The present invention relates to a composition for treating vascular diseases including protein phosphorylase 1 inhibitory peptides. The composition of the present invention inhibits not only non-ideal proliferation of vascular smooth muscle cells (VSMCs) but also PP-1 (protein phosphate 1) -mediated dephosphorylation to inhibit vascular endothelial cells. By activating eNOS of (vascular endothelial cells, VECs), recovery from dysfunction is induced, and it can be usefully used for treatment of vascular diseases including pulmonary arterial hypertension. [Selection] Fig. 1c本発明は、タンパク質脱リン酸化酵素1抑制ペプチド(protein phosphatase 1 inhibitory peptides)を含む血管疾患(vascular diseases)治療用の組成物に関するものである。本発明の組成物は、PP1(protein phosphatase 1)-媒介脱リン酸化を抑制して血管平滑筋細胞(vascular smooth nuscle cell、VSMCs)の非理想的な増殖を抑制するだけでなく、血管内皮細胞(vascular endothelial cells、VECs)のeNOSを活性化させることで、機能異常からの回復を誘導し、肺動脈高血圧を含む血管疾患の治療に有用に使用することができる。【選択図】図1c