Plasticity of behavioural response to repeated injection of glutamate in cuneiform area of rat.
Whereas a single microinjection of L-glutamate (10 nmol) into the cuneiform area of rats gives freezing, a second or third injection (delivered at 4-min intervals to the same site)can produce fast running. To examine whether this plasticity of response was caused by a simple increase in the amount of glutamate present, 30 nmol of glutamate were given in a single injection. In 93% of sites in the cuneiform area this procedure gave only freezing, although subsequent testing with repeated injections produced fast running in 53% of these sites. Thus, response potentiation to glutamate appears to require repeated stimulation, and may therefore be related to processes underlying the natural conditioning of defensive responses.
Mitchell
I J
IJ
Department of Psychology, University of Sheffield, U.K.
Redgrave
P
P
Dean
P
P
D000818:Animals; D005260:Female; D005971:Glutamates / Q000008:administration & dosage / Q000494:pharmacology*; D008845:Microinjections; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D013477:Superior Colliculi / Q000187:drug effects / Q000502:physiology*
D005971:Glutamates