Behavioral Effects of Low Doses of Cholinesterase Inhibitors in Robot- Tested Marmosets
Abstract
In two series, the effects on performance were tested 30 min after the i.m. injection of pyridostigmine (0.2-0.8 mg/kg) and 20 min after i.m. physostigmine (0.02-0.08 mg/kg) in experimentally naive marmosets. The behavioral tasks in series 1 were hand-eye coordination, reaction time and a discrete-trial two-choice visual discrimination task. For series 2, the reaction time task was dropped because detection was unreliable and a substitute was introduced into the discrimination task, which was transformed into an operant task. All tasks were trained and tested in succession in one session per day. This appeared difficult for the animals and only approximately 50% of the animals reached an acceptable performance level at which testing became meaningful. On hand-eye coordination, the lowest doses of pyridostigmine (0.2 mg/kg) and of physostigmine (0.02 mg/kg) were still above the no-effect level. This was also true for the effect of physostigmine (0.02-0.04 mg/kg) in the operant discrimination task, but in this task pyridostigmine (0.2-0.4 mg/kg) had no effect, suggesting that the discrimination task is predominantly CNS- mediated. These dose-levels are at least 4 times lower than those found by British scientists (personal communication E.A.M. Scott and G.D. d'Mello). In a 2-day joint critical assessment session with these scientists, in our laboratory, suggestions aimed at increasing the number of animals that reach an acceptable level of performance, at which testing becomes meaningful, were incorporated in the training procedures for a subsequent series.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1989
- Accession Number
- ADA221382
Entities
People
- Bas Groen
- Ingrid Philippens
- Otto L. Wolthuis
- Raymond Vanwersch