Increased cerebrospinal fluid cAMP levels in Alzheimer's disease

Since increasing evidence suggests that upregulation of the cAMP-second mes senger system may be implicated in Alzheimer's disease neurodegeneration, w e have compared the cAMP and cGMP levels in cerebrospinal fluid (CSF) from patients with dementia of the Alzheimer type (DAT, n = 10) with those from nondemented age-matched controls (n = 10). Our results show that cAMP level s, but not cGMP, are significantly (p < 0.01) elevated in CSF from patients with DAT compared to those from nondemented controls. Moreover, a linear r egression analysis demonstrated a significant correlation (r = 0.62; p < 0. 01) between cAMP and tau protein levels in CSF when controls and patients w ith DAT were studied together. These results suggest that upregulation of c AMP-signaling pathway is implicated in Alzheimer's disease physiopathology. (C) 1999 Elsevier Science B.V. All rights reserved.