effects of cytokine storm on vascular endothelial cells

[50birds]

what sort of effects would massive cytokine release caused by viral infection of monocytes & macrophages have on the vascular endothelium? am i right in assuming it would lead to vascular instability?

[biohazard]

Not quite sure what you mean by viral infection of monocytes and macrophages, but in general the "cytokine storm" has various effects, of which increased vascular permeability is perhaps the most dangerous one.

The cytokines affect the vascular endothelium in a way that increases the vascular diameter and blood flow, and allows fluid (and immune cells) to quickly pass through the vascular walls into the tissues. When localized, this is a useful phenomenom as it ensures that enough immune cells can make it to the site of infection. But when systemic, like often in the case of the cytokine storm (what a stupid name, btw :P), this leads to a sudden drop of blood pressure, loss of consciousness followed by death. Cytokine storms have various other, potentially harmful effects as well.

Cytokine storms can take place in various situations, such as after exposure to microbial toxins, after certain viral infections (these rarely infect macrophages or T cells, though) or after incompatible organ transplants etc. Basically anything that can cause an exaggerated immune response that is stronger than needed or what the body can withstand.