Cardiovascular toxicity

Drugs, chemicals, or plants can produce toxic effects on the whole animal as well as on the heart. Twenty chemicals and drugs were selected to show that there is no specific uniform toxicity effect across animal species. It is recognized that certain chemicals are much more or less toxic than others because of their inherent mechanism. Some of the drugs that are recognized as antidotes for toxic chemicals are in and of themselves toxic. Alternately, it is proposed that certain animals selectively graze a particular plant specifically for its medicinal effects. Many toxic plants are relatively palatable and may be the only green plants available in the pasture during certain times of the year. Toxic plants may also be hidden within hay and inadvertently fed to the livestock. The toxicity of plants may be derived from their alkaloid compounds, proteins and amino acids (enzymes, glycoproteins), glycosides, oxalates, resins, tannins, and phenol compounds. Most plant toxins affecting the heart fall into the alkaloid and glycoside groups.