With 22 healthy subjects capillary and venous blood is taken within the scope of one single study round. Blood is taken from the test persons by trained specialist staff of two fingertips of each hand (a total of four fingertips). The capillary blood sampling occurs in 200 µ l Lithium-Heparin Sarsted Microvettes and in each case the first drop of blood is rejected. To guarantee a light blood decrease without strong mechanical pressure, the hands are warmed up before the capillary sampling required with the help of an electric blanket or by warm water roughly on room temperature.