Marinobufagenin (marinobufagin) is a

cardiotonic A cardiac stimulant is a substance which acts as a stimulant of the heart – e.g., via positive chronotropic or inotropic action. Examples of cardiac stimulant drugs are cocaine and methamphetamine Methamphetamine (contracted from ) is a p ...

bufadienolide Bufadienolide is a chemical compound with steroid structure. Its derivatives are collectively known as bufadienolides, including many in the form of bufadienolide glycosides (bufadienolides that contain structural groups derived from sugars). These ...

steroid A steroid is a biologically active organic compound with four rings arranged in a specific molecular configuration. Steroids have two principal biological functions: as important components of cell membranes that alter membrane fluidity; and a ...

. It can be found in the plasma and urine of human subjects with myocardial infarction, kidney failure, and heart failure. It is also secreted by the toad '' Bufo rubescens'' and other related species such as '' Bufo marinus''. It is a vasoconstrictor with effects similar to digitalis.

References

Vertebrate toxins Epoxides Bufanolides Diols {{biochem-stub