INFLUENCE OF TAPPING-TIME AND ATMOSPHERIC-PRESSURE ON CONCENTRATIONS OF MONOAMINE METABOLITES IN THE CEREBROSPINAL-FLUID - A PROSPECTIVE-STUDY IN FEMALE VOLUNTEERS

Lumbar puncture was performed on 12 healthy female volunteers at the L4-5 level. CSF concentrations of 5-HIAA, HVA and HMPG were included in turn as dependent variables in repeated analyses of covariance with age, height, tapping-time, atmospheric pressure and the distance on the spine in the lying position as regressors. Use or non-use of oral contraceptives was included as a nominal variable. Results obtained were confirmed by nonparametric statistics. We found significant relationships between 5-HIAA and HVA, respectively, and height when the concentrations per minute of tapping-time (nM/min) were used as dependent variables. Hypothetically, the tapping-time mirrors the transport of concentrated CSF from the cranial to the caudal region when sitting up. We also found significant influences of atmospheric pressure and the use or non-use of oral contraceptives on HMPG. The role of atmospheric pressure is not clear but it might contribute to the transport of HMPG from the periphery to the CSF or affect the outflow of HMPG from the lumbar CSF compartment. The contribution of oral contraceptives might reflect interactions in the cerebral catecholamine metabolism.