Influence of moxaverine hydrochloride on membrane curvature and microsieve filterability of red cells after exposure to hyperosmolarity and lactacidosis.

Using a combination of novel techniques to assess quantitatively the shape and the filterability of red blood cells (RBC) after exposure to stress conditions (400 mosmol/l, lactacidosis, pH 6.8), the effects of 1-benzyl-3-ethyl-6,7-dimethoxy-isoquinoline hydrochloride (moxaverine-HCl, Kollateral) were tested. The shape of freely suspended RBC was quantified using the tangent count procedure. The filterability (microrheological performance) of leukocyte-free RBC suspensions was determined by computer-assisted conductometry using novel precision metal microsieves with uniform pore diameter of 4.2 micron. Moxaverine, when present in doses between 10(-5) und 10(-2) mol/l while the RBC are stressed, restored both the normal discoid red cell configuration and the microrheological performance when tested under low shear stresses. The data show that moxaverine, a papaverine derivative, hitherto considered as a classical vasodilator exerts protective effects on RBC membrane curvature and whole cell microrheological behavior (performance). The protective effects manifest themselves when the RBC's are exposed to abnormal biochemical conditions such as they might occur in poststenotic areas, where hypoxic ischemia is known to lead to a combination of hyperosmolarity and lactacidosis which modify the RBCs.