Neuronal regeneration takes place in the primary relay of the ( ) olfactory system, the olfactory epithelium OE ; however, its synaptic target in the central nervous system, the olfactory ( ) bulb OB , undergoes continual neurogenesis but not true regeneration. In this review, cell interactions and growth factors regulating neurogenesis in both OE and OB are discussed. In addition, regulation o...

Although the most intensively studied mammalian olfactory system is that of the mouse, in which olfactory chemical cues of one kind or another are detected in four different nasal areas [the main olfactory epithelium (MOE), the septal organ (SO), Grüneberg's ganglion, and the sensory epithelium of the vomeronasal organ (VNO)], the extraordinarily sensitive olfactory system of the dog is also an...

The ability of animals to distinguish individual con-specifics influences many aspects of their behaviour, including choice of mate, territorial marking and mother-offspring interactions. In rodents, information about individuality is conveyed by chemical cues in their urine and body secretions. Hence, mice can be trained to discriminate the urine odour of congenic mice that differ only in gene...

The mammalian main olfactory epithelium (MOE) modifies its activities in response to changes in the chemical environment. This process is essential for maintaining the functions of the olfactory system and the upper airway. However, mechanisms involved in this functional maintenance, especially those occurring via paracrine regulatory pathways within the multicellular MOE, are poorly understood...

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 mammalian vomeronasal system is specialized in pheromone detection. The neural circuitry of the accessory olfactory bulb (AOB) provides an anatomical substrate for the coding of pheromone information. Here, we describe the axonal projection pattern of vomeronasal sensory neurons to the AOB and the dendritic connectivity pattern of second-order neurons. Genetically traced sensory neurons exp...

In mammals, each olfactory sensory neuron randomly expresses one, and only one, olfactory receptor (OR)--a phenomenon called the "one-neuron-one-receptor" rule. Although extensively studied, this rule was never proven for all ~1,000 OR genes in one cell at once, and little is known about its dynamics. Here, we directly tested this rule by single-cell transcriptomic sequencing of 178 cells from ...

learning ability and memory duration are two inseparable factors which can increase theefficiency of a living organism during its lifetime. trichgramma brassice bezdenko (hym.:trichogrammatidae) is a biological control agent widely used against different pest species.this research was conducted to study the olfactory associative learning ability and memoryduration of t. brassicae under laborato...

histopathology on the olfactory organ of a snakehead fish, channa punctatus (bloch, 1793) were assessed after exposing the fish to 2.5 mg/l and 5mg/l of cdcl 2 for 15 days, 30 days and 45 days. cellular organization of the epithelium was affected severely with degeneration of sensory and supporting cells and hyperplasia of basal cells and mucous cells. mucous cell proliferation indicates the up...