ZD 7288, an HCN channel blocker, attenuates chronic visceral pain in irritable bowel syndrome-like rats

Table 1 Abdominal withdrawal reflex scoring criteria

Score
0	No behavioral response to colorectal distention
1	Immobile during colorectal distention and occasional head clinching at stimulus onset
2	Mild contraction of the abdominal muscles but absence of abdomen lifting from the platform
3	Observed strong contraction of the abdominal muscles and lifting of the abdomen off the platform
4	Arching of the body and lifting of the pelvic structures and scrotum