Ventricular cerebrospinal fluid (CSF) values of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA) and cyclic adenosine-3, 5-monophosphate (cAMP) were determined every 2 or 3 hours over a period of 1 to 3 days in 4 patients, consisting of two cases of meningitis, one case of head injury and one case of cerebral aneurysm. Ventricular CSF samples were collected through a drainage tube inserted into the lateral ventricle in all cases. Concentrations of HVA, 5-HIAA and cAMP in ventricular CSF varied with time in all cases. Significant correlations were noted between HVA and 5-HIAA values in all cases, and between cAMP and HVA values and cAMP and 5-HIAA values in 2 cases each. However, no relationship of HVA, 5-HIAA and cAMP values to the sleep-awake cycle and meals could not be established in any cases.
These data may suggest that HVA, 5-HIAA and cAMP values in the ventricular CSF vary in parallel with each other with time.