X. Xu, K. Zmolek
tions and fish that received saline injections immediately following training. Therefore, neither the microinjec-
tion procedure itself nor the microinjection of saline to the goldfish telencephalon impaired active avoidance
conditioning. Microinjections of carboxy-PTIO immediately following training impaired avoidance conditioning,
suggesting that extracellular NO may be necessary for forming memory of avoidance conditioning in goldfish.
The results of the current study confirm the finding that telencephalic NO is involved in memory consolidation
[10]. Thus, our previous results with D-AP5 [9] and current results with carboxy-PTIO together suggest that the
NMDA receptors are involved in learning or the process that is completed during training, whereas the NO is
involved in memory consolidation or the process that is normally completed sometime following the learning
experience.
Acknowledgements
This work was supported in part by a Grand Valley State University grant-in-aid.
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