Myocardial depressant factor (MDF) is a low-molecular-weight peptide

Peptide

Peptides are short polymers of amino acid monomers linked by peptide bonds. They are distinguished from proteins on the basis of size, typically containing less than 50 monomer units. The shortest peptides are dipeptides, consisting of two amino acids joined by a single peptide bond...

 released from the pancreas

Pancreas

The pancreas is a gland organ in the digestive and endocrine system of vertebrates. It is both an endocrine gland producing several important hormones, including insulin, glucagon, and somatostatin, as well as a digestive organ, secreting pancreatic juice containing digestive enzymes that assist...

 into the blood in mammals during various shock states.

MDF is a significant mediator of shock pathophysiology, reducing myocardial contractility, constricting splanchnic

Splanchnic

Splanchnic, from a Greek word spēn, meaning organ, usually used to describe visceral organs.More specifically, it can also refer to:* An adjective describing the intestines* Splanchnic nerves* Splanchnic mesoderm...

 arteries and impairing phagocytosis by the reticuloendothelial system

Reticuloendothelial system

"Reticuloendothelial system" is an older term for the mononuclear phagocyte system. The mononuclear phagocyte system consists primarily of monocytes and macrophages. The spleen is the largest unit of the mononuclear phagocyte system. The monocyte is formed in the bone marrow and transported by the...

. Survival can be improved by preventing its release or blocking its activity, for example using glucocorticoids, prostaglandin

Prostaglandin

A prostaglandin is any member of a group of lipid compounds that are derived enzymatically from fatty acids and have important functions in the animal body. Every prostaglandin contains 20 carbon atoms, including a 5-carbon ring....

s, aprotinin

Aprotinin

The drug aprotinin , is the bovine version of the small protein basic pancreatic trypsin inhibitor, or BPTI, which inhibits trypsin and related proteolytic enzymes. Under the trade name Trasylol, aprotinin was used as a medication administered by injection to reduce bleeding during complex surgery,...

, captopril

Captopril

Captopril is an angiotensin-converting enzyme inhibitor used for the treatment of hypertension and some types of congestive heart failure. Captopril was the first ACE inhibitor developed and was considered a breakthrough both because of its novel mechanism of action and also because of the...

, imidazole

Imidazole

Imidazole is an organic compound with the formula C3H4N2. This aromatic heterocyclic is a diazole and is classified as an alkaloid. Imidazole refers to the parent compound, whereas imidazoles are a class of heterocycles with similar ring structure, but varying substituents...

 or lidocaine

Lidocaine

Lidocaine , Xylocaine, or lignocaine is a common local anesthetic and antiarrhythmic drug. Lidocaine is used topically to relieve itching, burning and pain from skin inflammations, injected as a dental anesthetic or as a local anesthetic for minor surgery.- History :Lidocaine, the first amino...

.