A competitive NMDA receptor antagonist potentiates the effects of morphine on spatial and discrimination learning

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Laurence L. Miller (Creator)
Institution
The University of North Carolina Wilmington (UNCW )
Web Site: http://library.uncw.edu/
Advisor
Mark Galizio

Abstract: NMDA antagonists have been shown to attenuate the development of tolerance to the antinociceptive effects of morphine, but paradoxically, to potentiate the acute effects of morphine in assays of antinociception. In an effort to characterize the effects of these types of drugs on learning, morphine and the competitive NMDA antagonist, LY235959, were studied alone and in combination in two experiments. The first experiment utilized the Morris Swim Task, a procedure widely used to study spatial learning in rats. The second experiment used an olfactory discrimination procedure for rats. Both experiments involved the use of a within-subject, repeated acquisition and performance procedure (RAP). The RAP procedure allows the researcher to distinguish between a drug’s effects on learning versus more general performance effects. In both procedures, morphine produced selective impairments on acquisition, but LY235959 generally affected acquisition only at doses that also produced performance effects. Combinations of selected doses of the two drugs produced effects that suggest a potentiation of the effects that each drug produced alone.

Additional Information

Publication
Thesis
A Thesis Submitted to the University of North Carolina Wilmington in Partial Fulfillment Of the Requirements for the Degree of Master of Arts
Language: English
Date: 2009
Keywords
Drug testing--Research, Methyl aspartate--Receptors--Effect of drugs on, Morphine--Research, Neuropharmacology, Rats as laboratory animals--Research, Swimming--Physiological effect
Subjects
Drug testing -- Research
Morphine -- Research
Rats as laboratory animals -- Research
Swimming -- Physiological effect
Methyl aspartate -- Receptors -- Effect of drugs on
Neuropharmacology