The INDIVIDUALIST

A Wiki about biochemical individuality

Immunology

Description

The Schwartzman Phenomenon (Schwartzman Reaction) occurs when a small dose of endotoxin is injected subcutaneously resulting in a mild inflammation. When a second dose of endotoxin is injected intravenously, the original skin site injection site becomes hemorrhagic within a few hours. This reaction cannot be explained on the basis of immunity and is probably essentially toxic in nature.

Discussion

In many ways, the liver constitutes a "second line of defense" against substances which are able to pass the gut mucus membrane. In order for this to occur, nature has provided the liver with unique physical properties. For example, the liver possesses two blood supplies: the hepatic circulation which communicates with the regular veins and arteries of the body, and the portal circulation which is a separate circulation that exists between the gut and the liver. All blood return from the intestines is first sent to the liver via the portal circulation. This was designed to allow the liver an opportunity to clear this blood of immune complexes and microorganisms before they can find entry into the general circulation.

Within the body of the liver are specialized white blood cells called Kupffer cell. These cells have evolved into highly specialized filters of the portal circulation. As microorganisms or immune complexes reach the liver from the intestines, Kupffer cells activate and take up these particles and destroy them. This "filtered" blood is then allowed to enter the general circulation. This process starts at birth and continues throughout the lifetime. Under normal circumstances the liver is more than able to cope with this continuous blood. clearance. However under certain circumstances such as physical stress and illness or specialized diseases of the liver such as cirrhosis and hepatitis, unwanted and dangerous material may be able to evade the liver and enter the general circulation where it can "go systemic." This can then lead to the activation of the alternative complement pathway. Many botanicals are capable of raising the aggressiveness level of the Kupffer cells ('opsonizing").

In addition to its vascular functions, the liver has two other major responsibilities. It is responsible for the synthesis and secretion of bile, which is used to emulsify fats in the lower digestive tract. The liver is also responsible for a multitude of metabolic functions. These include: carbohydrate, protein and fat metabolism; the storage of vitamins and minerals; the formation and storage of a variety of hormones and chemical mediators; and the detoxification of internal and external toxins such as pesticides, drugs, and other hydrocarbons.

Endotoxins have been known to block their own absorption. This has been termed Schartzmann phenomenon, a poorly understood mechanism by which the hepatic clearance is blocked by a small amount of endotoxin, allowing a larger amount entry into the circulation.

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