Ricerche fisiologiche sulla distribuzione periferica del nervo depressore aortico destro nel cane

Summary The periferal distribution of the right aortic nerve has been studied in physiological experiments on the dog. It has been found that after section of both Hering's nerves and left vago-depressor trunk and after denervation of the baroceptor area ofMuratori-Nonidez lying at the root of the right subclavian artery, the electrical stimulation of one splancnic nerve or the intravenous injection of adrenaline still produces a reflex bradycardia; moreover the cooling of the vagus nerve still results in a rise of the blood pressure. It is inferred that a group of baroceptor fibres of the right aortic nerve originate from areas situated in the aortic region.     

Delay in skin allograft rejection in rats grafted with fetal adrenal glands

Resumen Se ha observado en este trabajo que el injerto de suprarrenales de fetos en ratas de 6 días de edad determina aumento del tiempo de supervivencia de aloinjertos de piel realizados al 10° día de vida en relación a los testigos y a ratas injertadas con suprarrenales de adulto. Un efecto similar se observó cuando se administró diariamente a partir del 6° día de vida 16-metil prednisona en dosis altas que producían gran trastorno del crecimiento, evidente disminución de peso del timo y en algunos casos muerte del animal.

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Fellow of the Consejo Nacional de Investigaciones Centificas y Técnicas (Argentina).     

Fungistatic action of the pigment secreted by the fungusEpicoccum nigrum link

Résumé On a constaté que le pigment sécrété par le mycèteEpicoccum nigrum a une réaction fungistatique sur leBoyrytis allii utilisé comme un organisme d'essai. Cette réaction a été dépendante du pH et a été assez basse aux niveaux dépassant 5.0.     

The effect of lidocaine on the secretion induced by cholera toxin in the cat small intestine

The intraluminal administration of lidocaine, a local anaesthetic agent, inhibits the net loss of fluid into the intestinal lumen produced by cholera toxin in the cat. It is suggested that the activation of a nervous reflex is involved in the pathogenesis of cholera.     

Protein kinase C injection into hippocampal pyramidal cells elicits features of long term potentiation

Long-term potentiation (LTP) in the hippocampus is an interesting example of synaptic plasticity because of its induction by physiological discharge rates and its long duration. Of the possible biochemical mechanisms that regulate prolonged changes in cell function, protein phosphorylation is a particularly attractive candidate. We have therefore examined the effect of intracellular injection of calcium/diacylglycerol-dependent protein kinase (protein kinase C (PKC] in CA1 pyramidal neurones in hippocampal slices. Injection of the active enzyme elicited long-lasting enhancement of synaptic transmission, similar to LTP, whereas inactivated kinase failed to do so. The observed changes included an increased amplitude of the excitatory post-synaptic potential (e.p.s.p.) and an increased probability of firing and a reduced latency of the associated actin potential.     

Low virulence and immunogenicity in mice and in rabbits of variants ofHerpes simplex virus resistant to 5-iodo-2-deoxyuridine

Résumé Par passage en série sur des cellules en culture et en présence de 5-iodo-2-desoxyuridine (IUdR) on a obtenu une souche de virus herpétique résistant à l'IUdR. Cette souche est très peu virulente chez la souris et le lapin, mais est capable de protéger ces animaux contre le virus pathogène d'origine.

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This work has been supported by a Grant of Consiglio Nazionale delle Ricerche, Roma.