Interplay between inflammation, immune system and neuronal pathways: Effect on gastrointestinal motility

Table 1 Overview of septic animal models displaying advantages and disadvantages (adapted from[18-20])

Endotoxin model

Advantages

Endotoxins play a significant role in the pathogenesis of sepsis

Simple model

Using sublethal doses, providing active resuscitation, using continuous infusion and the use of intraperitoneal injection are four measures reproducing more accurately the human situation

Lipopolysaccharides is stable (compared to the use of bacteria), therefore the model is more accurate and reproducible compared to the bacterial infection models

Disadvantages

Exaggerated release of host cytokines

Most of the time only Gram-negative sepsis

Single toxin does not mimic human sepsis

Therapies shown to be effective in animal models, failed in clinical trials

Rats are very resistant compared to humans

Lack of an infectious focus

Bacterial infection model

Advantages

Endotoxins play a significant role in the pathogenesis of sepsis

Reduction of the dose, increasing the infusion time, giving active resuscitation can prolong survival and render the model more comparable to the human situation

Disadvantages

Uncommon clinical occurrence

High doses of bacteria are needed

Significant interlaboratory variability

Survival is short

Serum cytokine responses are transient and exaggerated

Peritonitis model: cecal ligation puncture model

Advantages

Resemblance to clinical situation

Peritoneal contamination with a mixed flora

The cytokine response is comparable to human situation

Severity can be adjusted by increasing the needle puncture size or the number of punctures, delaying mortality over several days

Disadvantages

The model needs a surgical procedure that by itself may induce ileus

Difficult to control the magnitude of septic challenge

Variability within the cecal ligation puncture model