Alpha-trinositol attenuates
edema formation and capillary
albumin extravasation and lowering of interstitial fluid pressure (Pif) in several acute inflammatory reactions in rat skin or trachea. The lowering of Pif is an important driving force required to explain the rapid
edema formation in acute inflammatory reactions. The lowering of Pif and
edema formation are attenuated by
alpha-trinositol, which is suggested to act on the cellular
adhesion receptor for extracellular matrix components. This would represent a novel therapeutic strategy for acute
inflammation. To further clarify the mechanisms behind the anti-inflammatory effects of
alpha-trinositol, the effects of pre- and post-treatment with
alpha-trinositol on
edema formation and lowering of Pif were studied after subdermal injection of
carrageenan in the rat. The experiments measuring Pif showed that the lowering of Pif induced by
carrageenan was abolished by 10 mg
alpha-trinositol when administered either prior to or after injection of 5 microl 1% (w/v)
lambda carrageenan in the dorsum of the paw.
Edema formation after injection of
lambda carrageenan (100 microl, 1.5% w/v) into the foot pad was studied in a separate series. In control animals receiving saline vehicle, the volume of the paw injected with
carrageenan increased by approximately 30% after 3-4 h. The only significant effect of infusion of 20 mg kg(-1) h(-1)
alpha-trinositol was a reduction of
edema to approximately 20% when treatment was started 1 h before
carrageenan injection. Therefore, the plasma concentration of
alpha-trinositol must already be high when
carrageenan is injected in order to prevent
edema in the late phase. In conclusion, the present results indicate that the mechanisms involved in the lowering of Pif in the early phase of
edema development are different from those responsible for the manifest
edema measured 3-4 h after
carrageenan.