African crested rats cover themselves in cardiotonic glycosides?

Via the New York Times, this unusual news (article by Katherine J. Wu):  

Give them a chance and African crested rats will take nibbles from the branch of a poison arrow tree. It’s not for nutrition. Instead, they will chew chunks of the plants and spit them back out into their fur, anointing themselves with a form of chemical armor that most likely protects them from predators like hyenas and wild dogs. The ritual transforms the rats into the world’s only known toxic rodents, and ranks them among the few mammals that borrow poisons from plants....

...People in East Africa have long known about the crested rat’s poisonous punch, which has felled many an overcurious dog. (Those that survive their encounters tend to give the rats a wide berth.) In 2011, a team of researchers described the heart-stopping toxins that the rats milked from Acokanthera schimperi, a tree traditionally harvested by hunters who would use its juices to lace their arrows.

From Wikipedia, this description of the tree:

The bark, wood and roots of Acokanthera schimperi are used as an important ingredient of arrow poison in Africa. All plant parts contain acovenoside A and ouabaïne, which are cardiotonic glycosides. Its fruit is edible, and is eaten as a famine food.

 Guessing that overcurious dogs don't last long in Africa...