Digitalis purpurea pharmacological forms, extracts of this plant did not frequently cause intoxication because they induced nausea and vomiting within minutes of ingestion, preventing the patient from consuming more. The main toxins in "Digitalis" spp. are the two chemically similar cardiac glycosides: digitoxin and digoxin. Like other cardiac glycosides, these toxins exert their effects by inhibiting the ATPase activity of a complex of transmembrane proteins that form the sodium potassium ATPase pump, (Na/K-ATPase). Inhibition of the Na/K-ATPase in turn causes a rise not only in intracellular Na, but also in calcium, which in turn results in increased force of myocardial muscle contractions.
Plant physiology plants produce a vast array of chemical compounds with unique properties which they use to cope with their environment. Pigments are used by plants to absorb or detect light, and are extracted by humans for use in dyes. Other plant products may be used for the manufacture of commercially important rubber or biofuel. Perhaps the most celebrated compounds from plants are those with pharmacological activity, such as salicylic acid from which aspirin is made, morphine, and digoxin. Drug companies spend billions of dollars each year researching plant compounds for potential medicinal benefits. Plants require some nutrients, such as carbon and