 On study days volunteers will come to the study room at around 07:45 a.m. after an overnight fasting. After being weighed, they will remain in bed throughout the study, except when standing to pass urine. Two vein flow needles Venflon, Helsingborg, Sweden will be inserted in the antecubital veins of the right and left arm for the administration of infusions and blood sampling respectively. The subjects will rest for approximately 15 minutes before obtaining baseline blood samples at time point - 65 minutes. 