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 L 4-5 level. CSF concentrations of 5-HIAA, HVA and HMPG were included in turn as dependent variables in repeated analyses of covariance with a ge, height, tapping-time, atmospheric pressure and the distance on the spine in the lying position as regressors. Use or non-use of oral con traceptives was included as a nominal variable. Results obtained were confirmed by nonparametric statistics. We found significant relationsh ips between 5-HIAA and HVA, respectively, and height when the concentr ations per minute of tapping-time (nM/min) were used as dependent vari ables. Hypothetically, the tapping-time mirrors the transport of conce ntrated 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 pre ssure is not clear but it might contribute to the transport of HMPG fr om the periphery to the CSF or affect the outflow of HMPG from the lum bar CSF compartment. The contribution of oral contraceptives might ref lect interactions in the cerebral catecholamine metabolism.