Adaptive regulation of neuronal excitability by a voltage-independent potassium conductance.

Many neurons receive a continuous, or 'tonic', synaptic input, which increases their membrane conductance, and so modifies the spatial and temporal integration of excitatory signals. In cerebellar granule cells, although the frequency of inhibitory synaptic currents is relatively low, the spillover of synaptically released GABA (gamma-aminobutyric acid) gives rise to a persistent conductance mediated by the GABA A receptor that also modifies the excitability of granule cells. Here we show that this tonic conductance is absent in granule cells that lack the alpha6 and delta-subunits of the GABAA receptor.

Expression of the neuronal calcium sensor protein family in the rat brain.

The neuronal calcium sensor proteins are members of the calcium-binding protein superfamily. They control localized calcium signalling on membranes and may make G-protein cascades sensitive to cytosolic calcium. The family members are recoverin (visinin, S-modulin), neuronal calcium sensor-1 (frequenin), hippocalcin, neuronal visinin-like protein-1 (visinin-like protein, neurocalcin-alpha), neuronal visinin-like protein-2 and neuronal visinin-like protein-3.

Towers of Hanoi and London: is the nonshared variance due to differences in task administration?

Although it has been assumed that the Tower of Hanoi and Tower of London are more or less interchangeable tasks dependent on executive function, a series of studies in our laboratory have indicated substantial nonshared variance between the performances on the two tasks. The purpose of the present study was to examine how much methods of administration, such as number of trials per problem, contribute to this nonshared variance. A new one-trial version of the Tower of Hanoi was developed to be identical to the Tower of London in four procedural characteristics.

Autoradiographic characterisation of beta-adrenoceptors in chick brain using [3H]CGP 12177.

An autoradiographic method for labelling beta(1)- and beta(2)-adrenoceptors using [3H]CGP 12177 as a radioligand is described as well as the procedure for an autoradiographic saturation kinetic study. The method afforded higher quality autoradiographs as well as an improvement in the tissue preservation when assayed in birds and chick embryos. The results confirmed the K(d) values previously reported for membrane homogenate binding.