Decreased cerebrospinal fluid cGMP levels in patients with amyotrophic lateral sclerosis.

The role of cyclic guanosine 5' monophosphate (cGMP) in neurodegeneration of motor neurons in amyotrophic lateral sclerosis (ALS) is still controversial. The aim of this study was to measure levels of cGMP in cerebrospinal fluid (CSF) of patients with ALS, and to investigate whether there is a relationship between CSF cGMP levels and clinical parameters of the disease. The study involved 30 ALS and 20 control group patients. The CSF cGMP was measured by the enzyme-linked immunosorbent assay. The results showed that levels of CSF cGMP were significantly decreased in the group of ALS patients compared to controls and did not depend on clinical state of ALS patients, type of ALS onset, or the duration of the disease. Decreased levels of CSF cGMP observed in this study may suggest the role of cGMP in neurodegeneration in ALS. The CSF cGMP cannot be a marker of the disease activity.