Neuronal activity of raphe nuclei of the brain stem in the cat

Evoked potentials were recorded in the system of raphe nuclei in experiments on unanesthetized, immobilized cats. Somatic stimulation proved to be the most effective of the different stimulations used (light flash, sound click, electrical stimulation of the skin of the limbs). Sound and light stimulation did not evoke pronounced responses, or the latter (to sound) were of a very low amplitude and irregular. In the second series of experiments on cats narcotized with nembutal (30–35 mg/kg) the spontaneous activity and activity evoked by somatic stimulation of single neurons of the caudal part of the raphe nuclei were studied. The overwhelming majority of neurons were characterized by spontaneous activity which changed (inhibited or facilitated) under the effects of somatic (especially repeated) stimulation; most of them reacted to stimulation of the skin of any limb. In the case of paired stimulation of the skin of limbs on different sides at large intervals (40–60 msec), inhibition of the test discharge occurred, whereas at small intervals summation (simple addition) of the impulses occurred. In their general characteristics the neurons of the raphe nuclei apparently differ little from the neurons of the reticular formation of the brain stem.Institute of Electrophysiology, Academy of Sciences of the Georgian SSR, Tbilisi. Translated from Neirofiziologiya, Vol. 3, No. 1, pp. 32–42, January–February, 1971.     

Localization of non-native D-glyceraldehyde-3-phosphate dehydrogenase in growing and apoptotic HeLa cells

Monoclonal antibodies that could not bind native tetramers of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) but could bind to dimeric, monomeric, or denatured forms of GAPDH were used to investigate its intracellular localization. These antibodies distinctly stained the nucleus in growing HeLa cells. In the cytoplasm, non-native GAPDH was colocalized with actin filaments. Incubation of HeLa cells with tumor necrosis factor α (TNF-α) and the protein synthesis inhibitor emetine led to a drastic increase in the amount of the non-native GAPDH in the nuclei. Overproduction of Bcl-2 protein did not change the non-native GAPDH localization in the growing HeLa cells but prevented the development of apoptosis and the increase in the amount of non-native GAPDH in the nuclei upon incubation with TNF-α.