Effects of p-chlorophenylalanine on striatal acetylcholinesterase activity and on biogenic amine levels in nuclei raphe and caudate-putamen during physostigmine-induced tremor in rats.

Abstract

The biochemical mechanism underlying tremor is unknown. We investigated the effects of p-chlorophenylalanine (pCPA), a serotonin (5-HT) depletor, on the neurochemical processes in nuclei raphe dorsalis (NRD) and caudatus putamen (NCP) paralleling physostigmine-induced tremor in rats. Peak of physostigmine tremor correlated with increase in 5-HT in NRD and NCP, and a decrease in striatal dopamine (DA), as assayed employing high pressure liquid chromotography-electrochemistry. Administration of pCPA caused significant decrease in DA, norepinephrine (NE) and 5-HT levels in both the nuclei, without affecting striatal NE content and acetylcholinesterase activity. pCPA pretreatment significantly inhibited physostigmine-induced tremor and blocked corresponding increase in the levels of 5-HT in NRD and NCP. These results indicate involvement of central 5-HT, but not DA or NE, in the genesis of physostigmine tremor.

• Authors: H Mehta, B Thomas, K P Mohanakumar
• Journal: Neuroscience letters (Neurosci Lett) Vol. 299 Issue 1-2 Pg. 105-8 (Feb 16 2001) ISSN: 0304-3940 [Print] Ireland
• PMID: 11166949 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biogenic Amines
• Cholinesterase Inhibitors
• Serotonin Antagonists
• Serotonin
• Physostigmine
• Acetylcholinesterase
• Fenclonine
• Dopamine
• Norepinephrine

Topics

• Acetylcholinesterase (drug effects, metabolism)
• Animals
• Biogenic Amines (metabolism)
• Cholinesterase Inhibitors (pharmacology)
• Dopamine (metabolism)
• Fenclonine (pharmacology)
• Neostriatum (drug effects, enzymology)
• Norepinephrine (metabolism)
• Physostigmine (pharmacology)
• Raphe Nuclei (drug effects, metabolism)
• Rats
• Rats, Sprague-Dawley
• Serotonin (metabolism)
• Serotonin Antagonists (pharmacology)
• Tremor (chemically induced, enzymology, physiopathology)