Final answer:
Cholera enterotoxin is the substance released by intestinal bacteria that travels to the liver and initiates further liver damage.
Step-by-step explanation:
The substance released by intestinal bacteria that travels to the liver and initiates further liver damage is cholera enterotoxin. When V. cholerae bacteria attach to epithelial cells in the intestines, they release this toxin. The toxin increases cyclic AMP levels within the intestinal cell, activating a chloride channel and resulting in the release of ions and water into the intestinal lumen. As a result, profuse diarrhea occurs, leading to rapid dehydration and electrolyte imbalance.