جستجوی مقالات مرتبط با کلیدواژه « olfactory bulb » در نشریات گروه « پزشکی »

Olfactory system may be considered as a target for deep brain stimulation. In experimental researches, it is difficult to insert an electrode in the olfactory epithelium (OE) of laboratory animals, including mice, through nasal cavity.  Therefore, it is necessary to find a method for insertion of electrodes in the OE. In the present study we introduce a new method for electrode implantation in mice OE. Male C57BL/6 mice, aged 3-4 months were used. Animals were anesthetized and a pair of bipolar electrodes were inserted into the OE through a hole on the nasal bone. Field potential recordings were made from olfactory bulb and confirmed the electrode positions in OE, so that OE stimulation led to field excitatory post synaptic potentials (fEPSP) in olfactory bulb. In addition, considering the connection between olfactory system and hippocampus, the fEPSPs were also recorded in the hippocampus after a long synaptic delay. On the whole, we introduced a method for OE stimulation in mice as a common laboratory animal. This methos may be suitable in deep brain stimulation experiments in different animal models of neurological diseases.

Olfactory ensheathing cells (OECs) are widely used in transplantation studies. The high purification of this unique cell type is valuable for medical applications. Although recent improvements in OECs isolation procedures opened a new era in this field, the high purification efficacy and viability rate are still of concern. The most widely used OECs isolation techniques can be broadly classified based on adherence properties, particularly in olfactory bulb-derived OEC isolation. Considering the invasive nature of harvesting OECs from human olfactory bulbs, a highly efficient purification of these cells from olfactory mucosa can benefit clinical trials. In this study, we isolated OECs from rats’ olfactory bulbs and mucosa due to their differential adherence properties and compared them. 

Cell preparations were characterized by NGFR p75 and S100β antibodies, the specific markers for OECs, using immunocytochemistry and western blot analysis, respectively. OECs morphology and viability were monitored over time by microscopy and MTT (3-[4,5-dimethylthiazol2-yl]-2,5-diphenyltetrazolium bromide) assay. 

We found that OECs could be purified from the olfactory mucosa using our suggested method as efficiently as the olfactory bulb. Both derived OECs showed high levels of NGFR p75 and S100β expression, although the S100β expression was higher in olfactory mucosa-derived OECs preparations (P<0.05). Moreover, there was no significant difference between the two sources in cell viability in our suggested protocol. 

Due to the non-invasive harvesting method, olfactory mucosa-derived OECs are preferred from a clinical point of view in transplantation studies.

The Olfactory bulb is a crucial structure involved in olfaction that is located in the ventral anterior of the forebrain. Due to physiological and anatomical connection between olfactory and emotion processing networks, olfactory dysfunction is seen in some psychiatric disorders. Strong evidences suggest that olfactory bulb volume can mirror olfactory system function. Due to this correlation, there has been an interest to investigate the possible correlation between reduction of olfactory bulb volume and some neuropsychiatric disorders. Nowadays, mental disorders are mostly diagnosed according to behavioural symptoms. Gradual progression of mental disorders and delayed onset of behavioral symptoms have increased the importance of finding objective biomarkers. Such biomarkers can improve treatment outcome, accuracy of diagnosis, and prognosis. It is hypothesized that the reduction of olfactory bulb volume could be a biomarker for some disorders. In this article, we reviewed studies on the association of olfactory bulb volume with depression, Alzheimer’s disease, Parkinson’s disease, migraine, and multiple sclerosis.