Background synaptic activity in rat entorhinal cortex shows a progressively greater dominance of inhibition over excitation from deep to superficial layers

The entorhinal cortex (EC) controls hippocampal input and output, playing major roles in memory and spatial navigation. Different layers of the EC subserve different functions and a number of studies have compared properties of neurones across layers. We have studied synaptic inhibition and excitation in EC neurones, and we have previously compared spontaneous synaptic release of glutamate and GABA using patch clamp recordings of synaptic currents in principal neurones of layers II (L2) and V (L5). Here, we add comparative studies in layer III (L3). Such studies essentially look at neuronal activity from a presynaptic viewpoint. To correlate this with the postsynaptic consequences of spontaneous transmitter release, we have determined global postsynaptic conductances mediated by the two transmitters, using a method to estimate conductances from membrane potential fluctuations. We have previously presented some of this data for L3 and now extend to L2 and L5. Inhibition dominates excitation in all layers but the ratio follows a clear rank order (highest to lowest) of L2>L3>L5. The variance of the background conductances was markedly higher for excitation and inhibition in L2 compared to L3 or L5. We also show that induction of synchronized network epileptiform activity by blockade of GABA inhibition reveals a relative reluctance of L2 to participate in such activity. This was associated with maintenance of a dominant background inhibition in L2, whereas in L3 and L5 the absolute level of inhibition fell below that of excitation, coincident with the appearance of synchronized discharges. Further experiments identified potential roles for competition for bicuculline by ambient GABA at the GABAA receptor, and strychnine-sensitive glycine receptors in residual inhibition in L2. We discuss our results in terms of control of excitability in neuronal subpopulations of EC neurones and what these may suggest for their functional roles. © 2014 Greenhill et al.

Stray dogs in Bucharest, and the political economy of Romanian socialism. From hunting the “enemies” of Stalinist economy, to poisoning urban parasites, and the rise of urban anarchy: 1950s-1990s.

My paper discusses three different ways in which stray dogs have been intertwined with ideologies of economic and urban development in Romania. I categorize results from archival and ethnographic research under three major time periods: early socialism, late socialism, and post-socialism. During early socialism stray dogs were seen to be damaging the soviet economy by killing species that humans could also hunt, like rabbits. During late socialism, stray dogs appeared as the enemies of the communist city, and the department of urban sanitation was given orders to poison dogs with strychnine. Finally, the increasing number of stray dogs in Bucharest after the collapse of communism was seen as a direct result of former communist demolitions, and was also taken as a sign of the collapsing state. Through such examples my paper discusses how the state and particular population groups have seen dogs as parts of an unwanted and dangerous nature, rather than a species that needs to be protected. I argue that distinctions of nature and culture have served discourses of civilization and the view of Bucharest as a model socialist, and then European city. Throughout my paper I juxtapose the treatment of stray dogs with other, more “valued” urban natures like the protection of parks, the wide-spread hobby of pigeon breeding during socialist years, the most recent debate on saving the rural area of Rosia Montana from non-environmentally friendly methods of gold extraction, and the current trend of healthy eating and living.