Experiments on the effect have been performed by introducing a compound called angiotensin II into the blood stream of a rat. This compound narrows the diameter of the blood vessels, which increases the blood pressure and leads to the formation of the "sausage-string" pattern in the blood vessels. If the angiotensin II is removed, the blood vessel returns to its previous shape. Gustafsson's group suggests that the shape of the blood vessel becomes unstable at high blood pressure if the inner radius of the vessel becomes perturbed.

Gustafsson and co-workers defined a quantity, I(r), in terms of the dimensions and elastic properties of the vessels. If I(r) is positive, then the stress on the vessel increases in such a way to keep the blood vessel cylindrical in shape. However, if I(r) is negative, the radius of the vessel at that point becomes smaller, increasing the pressure and causing blood to flow away from this region. This further reduces the radius, eventually leading to the "sausage-string" pattern in the vein. According to their equations, the length of each "sausage" should be 5-10 times the radius of the vessel, which is backed up by experimental evidence. The theory also explains why similar patterns are not seen in larger blood vessels.