Neuropeptide Y levels in central and peripheral cerebrospinal fluid in patients with intracranial disorders.

Neuropeptide Y (NPY) was measured in central and peripheral cerebrospinal fluid (CSF) in patients suffering from various intracranial disorders. The central NPY-like immunoreactivity (LI) level showed a concentration of 129 +/- 19 pmol.l-1 and was significantly increased (p less than 0.05) compared to peripheral CSF (73 +/- 9 pmol.l-1). From five patients with subarachnoid haemorrhage the CSF NPY-LI levels reached 154 +/- 47 pmol.l-1. In five patients peripheral and central CSF was collected at the same occasion and the CSF NPY-LI concentration was 76 +/- 17 pmol.l-1 in peripheral and 142 +/- 23 pmol.l-1 in central CSF (p less than 0.01), respectively. In a reference group of 9 patients, who were examined by lumbar myelography because of suspected intervertebral herniated discs, the peripheral CSF NPY-LI concentration was 59 +/- 5 pmol.l-1 a value which was also significantly lower compared to NPY-LI levels in central CSF. Thus it is obvious that NPY is present in human CSF with a relatively higher concentration in central than in peripheral CSF at least in patients with disorders of the central nervous system, suggesting a central origin of the NPY.