A preliminary study of the effects of intravenous m-chlorophenylpiperazine, a serotonin agonist, in elderly subjects.
m-Chlorophenylpiperazine (m-CPP), a serotonin receptor agonist, is currently being investigated as a probe of serotonergic responsivity in various neuropsychiatric disorders. The safety of m-CPP in elderly populations and its potential usefulness in exploring possible serotonergic dysfunction in Alzheimer's disease and normal aging were assessed by examining the behavioral, neuroendocrine, and physiological effects of this agent in 15 elderly subjects (mean age 69 +/- 2 years): 9 Alzheimer patients and 6 healthy normal volunteers. Intravenous m-CPP (0.08 mg/kg) was well tolerated in all subjects and produced no serious adverse effects. The behavioral effects were modest; in particular, minimal anxiety was observed, a finding that contrasted to results from an earlier study reporting that intravenous m-CPP at a slightly higher dose induced marked anxiety and panic attacks in younger subjects. m-CPP produced significant increases in plasma cortisol and prolactin, and significant changes in blood pressure and temperature in these elderly subjects. The results of this preliminary study suggest that intravenous m-CPP is safe and well-tolerated in elderly subjects. Future studies at higher doses can now proceed to study more definitively the question of possible age- and disorder-related reductions in central nervous system (CNS) serotonergic responsivity.
Lawlor
B A
BA
Unit on Geriatric Psychopharmacology, National Institute on Mental Health, Bethesda, MD 20892.
Sunderland
T
T
Mellow
A M
AM
Hill
J L
JL
Newhouse
P A
PA
Murphy
D L
DL
D000368:Aged; D000544:Alzheimer Disease / Q000188:drug therapy*; D001288:Attention / Q000187:drug effects; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D007262:Infusions, Intravenous; D008297:Male; D011939:Mental Recall / Q000187:drug effects; D009483:Neuropsychological Tests; D010879:Piperazines / Q000008:administration & dosage* / Q000009:adverse effects; D011388:Prolactin / Q000097:blood; D014706:Verbal Learning / Q000187:drug effects
D010879:Piperazines; D011388:Prolactin; C015068:1-(3-chlorophenyl)piperazine; D006854:Hydrocortisone