Norepinephrine (NE) has various modulatory roles in both the peripheral and the central nervous systems. Here we investigate the function of the locus coeruleus efferent fibres in the olfactory bulb of Xenopus laevis tadpoles. In order to distinguish unambiguously between mitral cells and granule cells of the main olfactory bulb and the accessory olfactory bulb, we used a slice preparation. The...

Olfactory bulb interneuron development is a complex multistep process that involves cell specification in the ventral telencephalon, tangential migration into the olfactory bulb, and local neuronal maturation. Although several transcription factors have been implicated in this process, how or when they act remains to be elucidated. Here we explore the mechanisms that result in olfactory bulb in...

PURPOSE The aim of this study was to assess whether migration of thallium-201 ((201)Tl) to the olfactory bulb were reduced in patients with olfactory impairments in comparison to healthy volunteers after nasal administration of (201)Tl. PROCEDURES 10 healthy volunteers and 21 patients enrolled in the study (19 males and 12 females; 26-71 years old). The causes of olfactory dysfunction in the ...

* Present address: Biological Research Lab., Tanabe Seiyaku Co ., Ltd., Osaka, Japan. Abstract-In order to clarify the neural mechanisms underlying the hyperemotion ality induced by bilateral olfactory bulb ablations in rats, changes in emotional be havior were measured after various parts of the secondary olfactory structures had been lesioned and olfactory bulb ablations had been carried out....

This work describes a biophysical model of the initial stages of vertebrate olfactory system containing structures representing the olfactory epithelium and bulb. Its main novelty is the introduction of gap junctions connecting neurons both in the epithelium and bulb, and of biologically detailed dendrodendritic synapses between granule and mitral cells in the bulb. The model was used to simula...

The expression of hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, the c-met proto-oncogene product, was examined by in situ hybridization in the developing and adult murine olfactory system and compared with the expression of a known activator of HGF/SF, tissue-type plasminogen activator (tPA). In the developing olfactory canal, expression of both c-met and tPA was observed i...

The Notch signalling pathway is an important mediator of cell fate selection whose involvement in epidermal appendage formation is now becoming recognised. Hair follicle development and hair formation involve the co-ordinated differentiation of several different cell types in which Notch appears to have a role. We report intricate expression patterns for the Notch-1 receptor and three ligands, ...

Electrical stimulation of nerve fibers emerging from different positions of the olfactory epithelium was used to determine the receptive fields for 52 olfactory bulb neurons in the hamster. The responses of olfactory bulb neurons were recorded extracellularly with metal-filled micropipettes. Suprathreshold stimuli (500 microA) were applied to each of eight standard epithelial positions spaced a...

The olfactory bulb is a protruding structure formed at the rostral end of the telencephalon. Pax6-mutant mice and rats lack the olfactory bulb and, instead, develop an olfactory bulb-like structure at the lateral part of the telencephalon. Here, we report that ectopic formation of the olfactory bulb-like structure in these mutants is caused by the abnormal migration of mitral cell progenitors, ...

During olfactory development axons from the sensory epithelium migrate to the olfactory bulb and gradually establish connections with targeted glomeruli (Key and St John, 2002). The spatial distribution of these connections form the basis of a topographical mapping of odorant receptors onto the olfactory bulb (Vassar et al., 1994). The olfactory epithelium retains its capacity to undergo neurog...