Healthy granulation tissue played an important role in the wound healing process. However, some factors which interfered the process would result in unhealthy granulation tissue. Unhealthy granulation tissue may affect wound repairing. This article would focus on the concept, mechanisms, interventions of unhealthy granulation tissue.

AIM:To investigate the effects of voltage-dependent K +channel 1.5 (Kv1.5) on the proliferation and apoptosis of rat pulmonary artery smooth muscle cells (PASMCs) under hypoxia+hypercapnia condition and the relation-ship with mitogen-activated protein kinase(MAPK) signal pathway.METHODS:The PASMCs isolated from the male SD rat were cultured under hypoxia +hypercapnia condition, and randomly divided into normal group (N group), hypoxia+hyper-capnia group (HH group), hypoxia+hypercapnia+DMSO incubation group (HD group), hypoxia+hypercapnia +U0126 (an extracellular signal-regulated kinase 1/2 inhibitor) incubation group (HU group), hypoxia+hypercapnia+SB203580 (a p38 mitogen-activated protein kinase inhibitor ) incubation group (HS group), and hypoxia+hypercapnia+anisomycin (an agonist of MAPK) incubation group (HA group).Cell Counting Kit-8 was used to detect the cell viability.The protein expression of Kv1.5, PCNA and Bax was detected by Western blotting .RESULTS:Compared with N group , the cell via-bility and PCNA protein expression in HH group and HD group were significantly raised (P<0.01), but Kv1.5 and Bax proteins were significantly decreased (P<0.01).No difference between HH group and HD group was observed (P>0.05 ) .Compared with HD group , the cell viability and PCNA protein expression in HU group , HS group and HA group were decreased (P<0.05 or P<0.01), but Kv1.5 protein and Bax protein were raised (P<0.01), with the most significant changes in HA group .CONCLUSION:The regulation of Kv1.5 to the proliferation and apoptosis of PASMCs under hy-poxia+hypercapnia condition might have a relationship with the activation of MAPK signal pathway .