Catecholamine concentrations in venous plasma and cerebrospinal fluid in normal and complicated pregnancy

The concentrations of adrenaline and noradrenaline were determined in venous plasma and cerebrospinal fluid (CSF) of 41 pregnant women at term scheduled for elective or 'hot' caesarean section and in 7 healthy non-pregnant women scheduled for elective surgery. Group 1: 10 pregnant women at term with a normal history of their pregnancy; group 2: like group 1, but in active labour for more than 4 h; group 3: 10 pregnant women with insulin-dependent diabetes mellitus with or without slightly elevated arterial blood pressure; group 4: 11 women with pre-eclampsia gravis; group 5: 7 healthy non-pregnant women of fertile age. The highest values of mean arterial blood pressure and of venous plasma noradrenaline were found in the pre-eclamptic group 4, mean arterial blood pressure and plasma noradrenaline levels correlated to each other. However, concentrations of noradrenaline in CSF in group 4 did not differ significantly from the other groups. It is speculated that a different origin of hypertension may be the reason for the normal noradrenaline concentrations in CSF. This finding is in contrast to earlier findings in which noradrenaline levels in CSF were elevated in patients with essential hypertension.