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Incorporation of Uridine into Polysomes of Mouse Brain during Extinction


MICE injected with radioactive uridine in a double isotope labelling technique and then trained for 15 min to avoid a shock by jumping to a shelf incorporated about 50% more radioactivity into brain RNA1 and polysomes2 than untrained mice yoked to them. Quiet mice, yoked mice, and mice that were subjected to thirty electric shocks at random intervals for 15 min all incorporated less radioactive uridine into brain RNA and polysomes than did the trained mice1,2. This indicates that the lights, buzzers, shocks, handling and activity have little effect.

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    Zemp, J. W., Wilson, J. E., Schlesinger, K., Boggan, W. O., and Glassman, E., Proc. US Nat. Acad. Sci, 55, 1423 (1966).

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    Adair, L. B., Wilson, J. E., Zemp, J. W., and Glassman, E., Proc. US Nat. Acad. Sci., 61, 606 (1968).

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    Schlesinger, K., and Wimer, R., J. Comp. Physiol. Psychol., 63, 139 (1967).

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    Noble, E. P., Wurtman, R. J., and Axelrod, J., Life Sci., 6, 281 (1967).

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    Adair, L. B., Wilson, J. E., and Glassman, E., Proc. US Nat. Acad. Sci., 61, 917 (1968).

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