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Excitatory synapses in the glomerular triad of frog olfactory bulb in vitro
No full textWhole-cell patch clamp recording techniques were applied to periglomerular (PG) cells in slices of the frog olfactory bulb (OB) to study the properties of the excitatory synapses in the triad formed by the olfactory nerve (ON) and the dendrites of mitral/tufted (MT) cells and PG cells. The postsynaptic response evoked by ON stimulation was glutamatergic and could be dissected into NMDA and non-NMDA components of equivalent amplitudes. The dendro-dendritic synapse between MT and PG cells could be activated following antidromic stimulation of the lateral and medial olfactory tract (LOT and MOT). In this case the postsynaptic potentials had amplitudes and durations comparable to those obtained by ON stimulation, the neurotransmitter was glutamate, but the synapse was largely dominated by the slow NMDA component
Potassium currents in periglomerular cells of frog olfactory bulb in vitro
No full textVoltage-activated currents have been recorded from periglomerular cells in thin slices of frog olfactory bulb. Cells were examined with whole-cell patch clamp methods. The voltage-dependent potassium currents were studied after pharmacological block of inward currents. Depolarising steps from -130 mV gave an early transient, A-type, outward current and a delayed rectifier K+ current (IKV). The two currents could be isolated on the basis of the differences in their kinetic properties. The A-current developed following a third-order kinetics when the membrane was depolarised to potentials more positive than -40 mV after preconditioning to potentials more negative than -60 mV. Once activated (tau a 2.5 ms at 0 mV), IA inactivated following a single exponential (tau ha about 60 ms). IKV activated with a second-order kinetics above -30 mV with a time constant of 4 ms at 0 mV. IA and IKV were sensitive, respectively, to 4-aminopyridine (4-AP) and tetraethylammonium (TEA)
Distribution and function of the antennal olfactory sensilla in Ceratitis capitata Wied. (Diptera, Trypetidae)
No full textVALUTAZIONI NEUROFISIOLOGICHE COMPARATIVE TRA LA NEURORAFFIA ESEGUITA CON METODICA MICROCHIRURGICA E CON COLLA DI FIBRINA: STUDIO SPERIMENTALE
No full textOlfactory sensitivity to amino acids in the juvenile stages of the European eel Anguilla anguilla (L.)
No full textScanning electron micrograph observations of the olfactory mucosa from both unpigmented glass
eel(GE)andpigmentedelvers(EL)ofthe Europeaneel, AnguilluunguiNa(L.),revealed the presence
of various cell types; amongst these, the ciliated and microvillous ones are likely to possess a
chcmosensory function. Recording of underwater electro-olfactograms (EOGs) showed that
various amino acids (glycine, L-alanine, L-valine, L-leucine, L-asparagine, L-glutamine and Lmethionine)
are effective stimulants for the olfactory mucosa. Dose response curves of stimulus
concentrations v. EOG amplitudesfit regression linesat both GEand ELstages. Leucine wasmore
stimulatory at the GE than at the ELstage. The stimulatory effect ofthe other six amino acids tested
was similar at both developmental stages. The possible role of olfactory sensitivity in animal
behaviour at different developmental stages is discussed
LA RIPARAZIONE DI LESIONI DI NERVI PERIFERICI CON COLLA DI FIBRINA: RICERCA SPERIMENTALE
No full textOlfactory sensitivity to aminoacids in the juvenile stages of the European eel Anguilla anguilla (L.)
No full textScanning electron micrograph observations of the olfactory mucosa from both unpigmented glass eel(GE)andpigmentedelvers(EL)of the European eel, Anguilla anguilla(L.), revealed the presence of various cell types; amongst these, the ciliated and microvillous ones are likely to possess a chcmosensory function. Recording of underwater electro-olfactograms (EOGs) showed that various amino acids (glycine, L-alanine, L-valine, L-leucine, L-asparagine, L-glutamine and L-methionine) are effective stimulants for the olfactory mucosa. Dose response curves of stimulus concentrations v. EOG amplitudesfit regression linesat both GE and EL stages. Leucine was more stimulatory at the GE than at the EL stage. The stimulatory effect of the other six amino acids tested was similar at both developmental stages. The possible role of olfactory sensitivity in animal behaviour at different developmental stages is discussed
Comparative neurophysiological assessments of nerve sutures performed by microsurgical methods and with fibrin glue: experimental study.
No full textThe authors carried out an experimental study to compare the regeneration of nerves repaired with human fibrin glue and those sutured with nylon. The experiments were performed on rat peroneal nerves; the degree of regeneration was assessed by the neurophysiological strain gauge method, which involved recording the intensity of isometric contraction of the extensor digitorum longus muscle, which is innervated by the peroneal nerve. The results showed that the nerves "glued" with fibrin exhibited better regeneration than those repaired by suture
RILIEVI NEUROFISIOLOGICI SULLE SUTURE SPERIMENTALI DEI NERVI PERIFERICI ESEGUITE CON TISSUCOL
No full text- …
