The possible involvement of brain microtubules in memory fixation.

Goldfish were trained to discriminate between two coloured lights. When colchicine was administered intracranially immediately after training it produced complete retrograde amnesia 2 days later, but the fish displayed considerable retention if instead the injection was given 1.25 h after training. If colchicine was administered 1.25 h before training the fish were able to learn as readily as control fish but then showed retrograde amnesia when tested 2 days later. It is suggested that colchicine may affect memory fixation by interfering with the fast transport of material needed to bring about a structural modification at certain synapses.

[1]  G. A. Kerkut,et al.  The transport of 14C-labelled material from CNS⇌muscle along a nerve trunk , 1967 .

[2]  P. Greengard,et al.  Dopamine-sensitive adenylate cyclase in caudate nucleus of rat brain, and its similarity to the "dopamine receptor". , 1972, Proceedings of the National Academy of Sciences of the United States of America.

[3]  J. Sjöstrand,et al.  Effect of colchicine on the transport of axonal protein in the retinal ganglion cells of the rat. , 1971, Experimental eye research.

[4]  L. Landmesser,et al.  Axotomy Mimicked by Localized Colchicine Application , 1972, Science.

[5]  B W Agranoff,et al.  Memory fixation in the goldfish. , 1965, Proceedings of the National Academy of Sciences of the United States of America.

[6]  C. Sandri,et al.  Enlarged synaptic vesicles in optic nerve terminals induced by intraocular injection of colchicine. , 1972, Brain research.

[7]  B. Cragg.  The effects of vision and dark-rearing on the size and density of synapses in the lateral geniculate nucleus measured by electron microscopy. , 1969, Brain research.

[8]  R. Mark,et al.  Drug inhibition of memory formation in chickens II. Short-term memory , 1971, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[9]  M. Perišic,et al.  Synaptic Transmission Depressed by Colchicine Blockade of Axoplasmic Flow , 1972, Science.

[10]  J A Deutsch,et al.  The Cholinergic Synapse and the Site of Memory , 1971, Science.

[11]  H. Rasmussen.  Cell Communication, Calcium Ion, and Cyclic Adenosine Monophosphate , 1970, Science.

[12]  W. Muntz,et al.  EFFECTIVENESS OF DIFFERENT COLORS OF LIGHT IN RELEASING POSITIVE PHOTOTACTIC BEHAVIOR OF FROGS, AND A POSSIBLE FUNCTION OF THE RETINAL PROJECTION TO THE DIENCEPHALON , 1962 .

[13]  F. Volkmar,et al.  Rearing Complexity Affects Branching of Dendrites in the Visual Cortex of the Rat , 1972, Science.

[14]  M. Pichichero,et al.  Cyclic Adenosine Monophosphate Stimulation of Axonal Elongation , 1972, Science.

[15]  P. Greengard,et al.  Dopamine-Sensitive Adenyl Cyclase: Possible Role in Synaptic Transmission , 1971, Science.

[16]  J. Cronly-Dillon,et al.  Colour discrimination in goldfish. , 1966, Animal behaviour.

[17]  B. Agranoff,et al.  Camptothecin Blocks Memory of Conditioned Avoidance in the Goldfish , 1973, Science.

[18]  E. Bennett,et al.  Quantitative synaptic changes with differential experience in rat brain. , 1971, The International journal of neuroscience.

[19]  J. Y. Lettvin,et al.  Comments on Microelectrodes , 1959, Proceedings of the IRE.

[20]  R. M. Gaze,et al.  TYPES OF VISUAL RESPONSE FROM SINGLE UNITS IN THE OPTIC TECTUM AND OPTIC NERVE OF THE GOLDFISH. , 1964, Quarterly journal of experimental physiology and cognate medical sciences.

[21]  M. Smith,et al.  The turnover of myelin in the adult rat. , 1968, Biochimica et biophysica acta.

[22]  H. Rasmussen,et al.  Cyclic adenosine 3':5'-monophosphate-stimulated phosphorylation of isolated neurotubule subunits. , 1970, Proceedings of the National Academy of Sciences of the United States of America.

[23]  M. Glick,et al.  MEMBRANES OF ANIMAL CELLS , 1968, The Journal of cell biology.

[24]  B W Agranoff,et al.  Actinomycin D Blocks Formation of Memory of Shock-Avoidance in Goldfish , 1967, Science.

[25]  G. F. Cooper,et al.  Development of the Brain depends on the Visual Environment , 1970, Nature.

[26]  Received December.  Apical Dendritic Spines of the Visual Cortex and Light Deprivation in the Mouse , 1967 .

[27]  S Ochs,et al.  Fast transport of materials in mammalian nerve fibers. , 1972, Science.

[28]  J. Cronly-Dillon,et al.  Units Sensitive to Direction of Movement in Goldfish Optic Tectum , 1964, Nature.

[29]  D. Hubel,et al.  The period of susceptibility to the physiological effects of unilateral eye closure in kittens , 1970, The Journal of physiology.

[30]  R. Mark,et al.  Drug inhibition of memory formation in chickens I. Long-term memory , 1971, Proceedings of the Royal Society of London. Series B. Biological Sciences.

[31]  A. Scheibel,et al.  The effect of visual deprivation on cortical neurons: a Golgi study. , 1967, Experimental neurology.

[32]  R. M. Gaze,et al.  Binocular interaction in the formation of specific intertectal neuronal connexions , 1970, Proceedings of the Royal Society of London. Series B. Biological Sciences.