Influence on handedness of acetylocholine locally applied with other chemicals to the cerebral cortex of the rat.

Abstract

Acetylcholine (Ach) seems to have a facilitating effect in the preferential use of the hands when applied locally to one hemisphere of the rat's brain (2). However, the results are equivocal when all of the experimental animals are taken into consideration. Only in ambidextrous rats is the effect likely to be observed and even in such cases, negative results appear as frequently as positive. Nevertheless, localized clonic contractions of the forelimb, which are also sporadic and uncertain but which are unequivocal when they do occur, lend support to the notion that some effect is being produced.Early work indicated that some means should be sought to increase the incidence of the change. The literature is replete with suggestions of ways to stabilize Ach in animal tissues, and thus make it more effective. Inhibitors of choline esterase, buffers to maintain acidity, changes in saline concentration, solvents natural to nerve tissue, associated drugs with similar central effects; all of these are possibilities which come to mind.

The effect of DFP on learning and retention following physiological recovery.

“…A considerable amount of investigation has been conducted bearing on the physiological action of DFP, but little has been reported on the effects of the drug on behavior (10). In a series of preliminary studies on the effects of subcutaneous injections of DFP on rat behavior, Platt and Wickens (11,12,13) found that with dosages of 1.45 mg/kg and of 2.00 mg/kg of DFP with an estimated LD 6 o of 2.5 mg/kg, food and water consumption was disrupted for a period of two weeks following injection.…”