Display substrate and display device

A display substrate, comprising:

• a signal line located in a display region of the display substrate, and an electro-static discharge unit and an electro-static lead-out line in a frame region of the display substrate, wherein
• the electro-static discharge unit comprises a first thin film transistor, a third thin film transistor and a fourth thin film transistor;
• a drain electrode and a gate electrode of the first thin film transistor are respectively connected to the signal line;
• a source electrode of the first thin film transistor, a gate electrode of the third thin film transistor and a gate electrode of the fourth thin film transistor are respectively connected to a first node;
• a drain electrode of the third thin film transistor and a drain electrode of the fourth thin film transistor are respectively connected to the signal line;
• a source electrode of the third thin film transistor and a source electrode of the fourth thin film transistor are respectively connected to the electro-static lead-out line,
• the electro-static discharge unit further comprises:
• a fifth thin film transistor;
• a drain electrode and a gate electrode of the fifth thin film transistor are respectively connected to the signal line;
• a source electrode of the fifth thin film transistor is connected to the first node.