OLFATO: forma más antigua de comunicación y sentido preciso que el otorrinolaringólogo debe conocer a profundidad / SMELL: oldest form of communication and precise sense that the otolaryngologist must know in depth

Introducción: el papel clave del olfato, antiguo sistema sensorial, es proporcionar información sobre las sustancias químicas en el medio ambiente. El olfato desempeña un papel en la detección de compuestos peligrosos, el mantenimiento de la nutrición, el comportamiento interpersonal, la salud neurológica y la sensación de placer, entre otras funciones. En consecuencia, la disfunción olfativa puede conducir a un riesgo de lesiones, desnutrición, aislamiento social y una mala calidad de vida. Materiales y métodos: se realizó una exploración bibliográfica y se identificaron artículos de acuerdo con los criterios de inclusión y exclusión definidos y se tomaron aquellos con calidad en la evidencia. Discusión: el sistema olfativo humano tiene diferencias anatómicas, fisiológicas y genéticas considerables con respecto al de otros mamíferos. Conclusiones: las destrezas olfativas varían con factores como la edad, el sexo, la etapa de desarrollo, ciertas enfermedades otorrinolaringológicas y enfermedades generales.

Introduction: The key role of the ancient olfactory sensory system is to provide information about chemicals in the environment. Smell plays a role in the detection of dangerous compounds, the maintenance of nutrition, interpersonal behavior, neurological health, and the sensation of pleasure, among other functions. Consequently, olfactory dysfunction can lead to a risk of injury, malnutrition, social isolation, and a poor quality of life. Materials and methods: A bibliographical exploration was carried out and articles were identified according to the inclusion and exclusion criteria defined and those with quality evidence were taken. Discussion: The human olfactory system has considerable anatomical, physiological, and genetic differences from that of other mammals. Conclusions: Olfactory skills vary with factors such as age, sex, stage of development, certain ear, nose and throat diseases and general diseases.

Olfactory nerve: from ugly duckling to swan / Nervo olfatório: de patinho feio a cisne

ABSTRACT Background: The olfactory nerve has never been the shining star of neurological examination. Quite the contrary, examining the first cranial nerve is often an overlooked step. As cases of anosmia secondary to COVID-19 infection continue to rise, the 2020 pandemic has shed new light on this much-forgotten nerve, its value as an aid to diagnosis of several diseases and its central role in our daily lives. Objective: We aimed to emphasize how essential and simple clinical examination of the olfactory system can be by highlighting practical techniques and clinical tips for its assessment. We also share pearls and pitfalls in localization and differential diagnosis, which may prove valuable to busy clinicians. Methods: A broad review of the literature was conducted by searching PubMed, Cochrane and Google Scholar for articles and books containing topics regarding examination of the olfactory nerve and its anatomy, physiology and pathology. No particular inclusion or exclusion criteria were used. Results: Forty different works were found, between books and articles, from which 20 were selected after careful analysis. Conclusions: Despite the tragedy and adversity that followed the COVID-19 pandemic, its legacy has taught us a crystal-clear lesson: olfaction should no longer be neglected in clinical practice.

RESUMO Antecedentes: O nervo olfatório nunca foi a estrela do exame neurológico. Pelo contrário, o exame desse nervo craniano é um passo frequentemente ignorado. No entanto, o aumento exponencial de casos de anosmia secundária a COVID-19 o colocou sob os holofotes, tanto em relação á sua função para o ser humano em sociedade, como seu papel no auxílio do diagnóstico de diversas patologias. Objetivos: Enfatizar quão importante é examinar o nervo olfatório e compreender as desordens do seu sistema. Ressaltamos pérolas clínicas e erros comuns no exame deste nervo, além dicas que possam auxiliar no diagnóstico de uma série de doenças neurológicas e sistêmicas. Métodos: Uma ampla revisão da literatura foi conduzida por meio de busca no PubMed, Cochrane e Google Acadêmico por artigos e livros relacionados aos tópicos do exame físico, fisiologia, anatomia e patologia do nervo olfatório. Não foram utilizados critérios específicos de inclusão ou exclusão. Resultados: Foram encontrados 40 artigos itens relacionados na língua inglesa, dentre os quais livros e artigos, tendo sido analisados e selecionados um a um até o total de 20 referências. Conclusões: Apesar da tragédia e adversidade trazidas pela pandemia de COVID-19, uma lição clara permanece: o olfato não deve mais ser negligenciado na prática clínica.

Inalação da fumaça do tabaco provoca alterações histopatológicas no nervo olfatório de ratas / Inhalation of tobacco smoke causes histopathological changes in the olfactory nerve of rats

Introdução: o tabagismo é uma das principais causas evitáveis de mortes no mundo representando um problema de saúde pública. Objetivo: investigar a relação da exposição passiva à fumaça principal do cigarro e as possíveis alterações histomorfométricas das células gliais, arteríolas e da matriz extracelular do nervo olfatório de ratas. Metodologia: trata-se de um estudo experimental, analítico e quantitativo. Vinte ratas randomizadas divididas em dois grupos, controle e tabaco, foram expostas à inalação da fumaça principal do cigarro por 60 dias utilizando dispositivo validado na literatura. Resultados: a exposição à inalação da fumaça principal do cigarro resultou em alterações significativas no grupo tabaco, tais como, elevação nos níveis de cotinina no plasma sanguíneo, aumento na espessura da parede dos vasos sanguíneos, aumento na porcentagem do colágeno total do tecido, diminuição no número total de astrócitos e aumento no número total de micróglias. Conclusão: a exposição à fumaça principal do cigarro resulta em alterações histomorfométricas que poderiam causar alterações funcionais no nervo olfatório como perda sensorial olfativa. Os achados constatados são fortes o suficiente para servir como alerta a toda a população e às autoridades de saúde, no que se refere às leis antifumo, principalmente em ambientes fechados.

Introduction: smoking is one of the main preventable causes of death in the world and represents a worldwide public health problem. Objective: to investigate the relationship of second hand tobacco smoke and possible histomorphometric changes of glial cells, arterioles and extracellular matrix of the olfactory nerve in rats. Methodology: experimental, analytical and quantitative study, twenty wistar animals randomized into two control and tobacco groups, were exposed to inhalation of main cigarette smoke for 60 days using a device validated in the literature. Results: exposure to inhalation of main cigarette smoke resulted in changes in the tobacco group, such as increased levels of cotinine in the blood plasma, increased thickness of the blood vessel wall, increased percentage of total tissue collagen, decreased in the total number of astrocytes and increase in the total number of microglia. Conclusion: exposure to main cigarette smoke results in histomorphometric changes that can cause changes in the olfactory nerve such as sensory olfactory loss. Our findings are strong enough to serve as a warning to the entire population and to health authorities in relation to smokefree laws especially in closed environments.

Nervios olfatorio, trigémino, facial, glosofaríngeo y vago: vínculos con sars-cov-2 y prospectivas neurosemiológicas / Olfactory, trigeminal, facial, glossopharyngeal and vagus nerves: links with sars-cov-2 and neurosemiological prospects

Se presenta una breve revisión los nervios olfatorio, trigémino, facial, glosofaríngeo y vago, el primero funcionalmente relacionado con la inervación quimiosensitiva olfativa en la mucosa nasal, los siguientes para el registro de dolor endocraneal y para la mucosa orofaríngea, a efectos de transducción sensitiva gustativa. Estos nervios se vinculan con los síntomas en pacientes positivos para Covid-19, que manifiestan como dolor de cabeza, disosmia, anosmia, disgeusia, ageusia entre otras características neurosemiológicas. Se concluye que estas características semiológicas se puedan deber a mecanismos neurotrópicos y transinápticos por lo que se debe realizar un examen neurológico más riguroso sobre síntomas y signos de pacientes con Covid-19.

A brief review of olfactory, facial, glossopharyngeal and vagus nerves is presented, the first one functionally related to odoriferous chemosensory innervation in the nasal mucosa, the following four cranial nerves to endocranial headache and oropharyngeal mucosa for purposes of gustatory sensory transduction. These nerves are associated with symptoms in Covid-19 positive patients, which dysosmia, anosmia, dysgeusia, ageusia manifestation, among other neurosemiological characteristics. It is concluded that these semiological characteristics may be due to neurotropic and transynaptic mechanisms, therefore a more rigorous neurological examination should be performed on symptoms and signs of Covid-19 patients.

Nervus terminalis and nerves to the vomeronasal organ: a study using human fetal specimens / 대한해부학회지

The human nervus terminalis (terminal nerve) and the nerves to the vomeronasal organ (VNON) are both associated with the olfactory nerves and are of major interest to embryologists. However, there is still limited knowledge on their topographical anatomy in the nasal septum and on the number and distribution of ganglion cells along and near the cribriform plate of the ethmoid bone. We observed serial or semiserial sections of 30 fetuses at 7–18 weeks (crown rump length [CRL], 25–160 mm). Calretinin and S100 protein staining demonstrated not only the terminal nerve along the anterior edge of the perpendicular lamina of the ethmoid, but also the VNON along the posterior edge of the lamina. The terminal nerve was composed of 1–2 nerve bundles that passed through the anterior end of the cribriform plate, whereas the VNON consisted of 2–3 bundles behind the olfactory nerves. The terminal nerve ran along and crossed the posterior side of the nasal branch of the anterior ethmoidal nerve. Multiple clusters of small ganglion cells were found on the lateral surfaces of the ethmoid's crista galli, which are likely the origin of both the terminal nerve and VNON. The ganglions along the crista galli were ball-like and 15–20 µm in diameter and, ranged from 40–153 in unilateral number according to our counting at 21-µm-interval except for one specimen (480 neurons; CRL, 137 mm). An effect of nerve degeneration with increasing age seemed to be masked by a remarkable individual difference.

Entrenamiento olfatorio: revisión de literatura / Olfactory training: review of literature

RESUMEN La disfunción olfatoria es una patología frecuente que trae consigo una disminución importante en la calidad de vida de los pacientes y que incluso conlleva una mortalidad aumentada respecto a la población general. Sin embargo, es una condición subdiagnosticada, ya sea por desconocimiento de los profesionales o por falta de un método diagnóstico adecuado. A la fecha no existe un tratamiento efectivo para estos pacientes y generalmente se les deja sin tratar. Una alternativa para este gran problema es el entrenamiento olfatorio, tratamiento propuesto recientemente con resultados promisorios.

ABSTRACT Olfactory dysfunction is a frequent pathology associated with an important decrease in the quality of life of patients and an increased mortality respect to the general population. However, it is an underdiagnosed condition, either due to lack of knowledge of the professionals or due to the lack of an adequate diagnostic method. To date there is no effective treatment for these patients and they are usually left untreated. An alternative to this problem is olfactory training, a treatment recently proposed with promising results.

Lesiones olfatorias postraumáticas: Revisión de la literatura / Post-traumatic olfactory injuries: Literature review

Las alteraciones del olfato son frecuentemente halladas en pacientes con lesión traumática cerebral. Las lesiones del nervio olfatorio pueden asociadas a equimosis periorbitaria, fistula de líquido cefalorraquídeo, epitaxis, fractura nasal y epitaxis. La disfunción olfatoria postraumática es de manera usual infraevaluada. Presentamos una revisión narrativa sobre los aspectos más relevantes de las lesiones postraumáticas del nervio olfatorio.

Alterations in smell are frequently found in patients with traumatic brain injury. Olfactory nerve lesions can be associated with periorbital ecchymosis, cerebrospinal fluid fistula, epistaxis, and nasal fracture. Posttraumatic olfactory dysfunction is usually under-appreciated. We present a narrative review of the most relevant characteristics of post-traumatic injuries affecting the olfactory nerve.

Subfrontal Schwannoma Extended Broadly to Nasal Cavity Treated by Gamma Knife Radiosurgery Following Surgical Excision: A Case Report

Subfrontal schwannomas are rarely reported. They are usually found only in the subfrontal area, but some extend to the nasal cavity. In these cases, prevention of postoperative cerebrospinal fluid (CSF) leakage through thinned or eroded anterior skull base is important. A 51-year-old female with anosmia and mild nausea was diagnosed as subfrontal extraaxial mass with nasal cavity extension. This mass was initially thought to be an olfactory groove meningioma. We performed a bifrontal craniotomy for surgical excision. We did not totally remove the tumor, as we wanted to prevent a skull base defect. The histopathological diagnosis was a schwannoma. There was no postoperative complication such as CSF leakage. The residual tumor was treated with gamma knife radiosurgery. The nasal cavity mass has not grown as of five years after radiosurgery.

Olfactory Dysfunction in Nasal Bone Fracture

BACKGROUND: All nasal bone fractures have the potential for worsening of olfactory function. However, few studies have studied the olfactory outcomes following reduction of nasal bone fractures. This study evaluates posttraumatic olfactory dysfunction in patients with nasal bone fracture before and after closed reduction. METHODS: A prospective study was conducted for all patients presenting with nasal bone fracture (n=97). Each patient consenting to the study underwent the Korean version of Sniffin' Sticks test (KVSS II) before operation and at 6 month after closed reduction. The nasal fractures were divided according to the nasal bone fracture classification by Haug and Prather (Types I–IV). The olfactory scores were compared across fracture types and between preoperative and postoperative settings. RESULTS: Olfactory dysfunction was frequent after nasal fracture (45/97, 46.4%). Our olfactory assessment using the KVSS II test revealed that fracture reduction was not associated with improvements in the mean test score in Type I or Type II fractures. More specifically, the mean posttraumatic Threshold, discrimination and identification score decreased from 28.8 points prior to operation to 23.1 point at 6 months for Type II fracture with septal fracture. CONCLUSION: Our study has revealed two alarming trends regarding post-nasal fracture olfactory dysfunction. First, our study demonstrated that almost half (46.4%) of nasal fracture patients experience posttraumatic olfactory dysfunction. Second, closed reduction of these fractures does not lead to improvements olfaction at 6 months, which suggest that olfactory dysfunction is probably due to factors other than the fracture itself. The association should be further explored between injuries that lead to nasal fracture and the mechanism behind posttraumatic olfactory dysfunction.

Las estrías olfatorias del ser humano y propuesta de inclusión en la terminologia anatomica de estría olfatoria intermedia / Olfactory stria in the human being and proposal for inclusion in terminologia anatomica of olfactory intermediate stria

Las estrías olfatorias del ser humano son dos divisiones del tracto olfatorio, tradicionalmente identificadas como medial y lateral, reconocibles a nivel del trígono olfatorio y asociadas con la corteza piriforme. El objetivo del presente trabajo fue estudiar tomando como referentes treinta y seis nervios olfatorios de cerebros frescos, la presencia de más de dos estrías olfatorias y verificar si hay estría olfatoria intermedia. Se concluye que las estrías olfatorias son variables en número de dos a tres y que se debe incluirse en la Terminologia Anatomica el término estría intermedia.

The human olfactory stria are two divisions of the olfactory tract, traditionally identified as medial and lateral olfactory stria, recognizable at the level of the olfactory trigone, and associated with the piriform cortex. The aim of this work was to study taking as reference thirty six fresh brain's olfactory nerves, the presence of more than two olfactory stria and check for intermediate olfactory stria. It is concluded that the olfactory stria are variable in number from two to three and this should be included in the Terminologia Anatomica as the term stria intermedia.

Effect of electro-acupuncture combined with olfactory ensheathing cell transplantation on spinal cord injury axonal regeneration and direction / 中国骨伤

<p><b>OBJECTIVE</b>To explore the impact and mechanism of electro-acupuncture (EA) on olfactory ensheathing cells (OECs) transplantation of spinal cord injury (SCI) axonal regeneration.</p><p><b>METHODS</b>In the experiment, 72 adult Sprague Dawley male rats weighted (220±20) g underwent contusion and transection method to cause the T9 model of spinal cord injury, were randomly divided into four groups involving model group, EA group,OECs group,and EA+OECs group. 5% fluorescein gold (FG) solution of 0.5 µl was injected into rats' spinal cord at 4 weeks and 8 weeks after SCI, a series of tests were performed including fluorescein gold(FG) retrograde tagging, BBB scores.</p><p><b>RESULTS</b>(1)The BBB scores level among four groups had no differences from the 1st day to the 1st week after the SCI (P>0.05). From the 3rd week after the SCI, the BBB scores level in EA+ OECs group were obviously higher than that of other groups (P<0.05). (2)The result of the fluorescein gold (FG) retrograde tagging showed at 4 weeks and 8 weeks after treatment FG positive nerve fibers were observed in SCI region. In EA+OECs group the number of FG positive nerve fibers was more than other three groups, and the fibers were more regularly arranged than other three groups.</p><p><b>CONCLUSION</b>The combination of electro-acupuncture and OECs transplantation can recover the pathway of nerve conduction and promote nerve fibers regeneration and hind limb function recovery for SCI rat, and can guide the trend of the axonal regeneration.</p>

Schwannoma of Ansa Cervicalis in the Submandibular Space / 대한이비인후과학회지

Although schwannomas can arise from all types of nerves except the optic and olfactory nerves, those that arise from the ansa cervicalis is extremely rare, with only four cases having been reported worldwide. Because of their rarity, ansa cervicalis schwannomas are rarely considered in patients presenting with schwannomas of the neck region. In the present case, we did not consider ansa cervicalis as the nerve of origin preoperatively, but during the surgery, found a mass originating from the ansa cervicalis by identifying a contracture of the strap muscles. We thus address the need to consider ansa cervicalis as a possible original site in the evaluation and management of schwannomas of the neck region. In addition, surgeons should focus on the intraoperative findings to determine the nerve of origin and to anticipate postoperative complications, as well as performing appropriate preoperative imaging studies.

A Case of Hypoglossal Neurilemmoma in the Submandibular Space / 대한이비인후과학회지

Although neurilemmomas can arise from all types of cranial nerves except the optic and olfactory nerves, a hypoglossal neurilemmoma is extremely rare. Furthermore, since this neurilemmoma usually develops in the intracranial portion of the hypoglossal nerve, a hypoglossal neurilemmoma in the submandibular region is unfamiliar even to head and neck surgeons. However, the preoperative diagnosis of hypoglossal neurilemmoma in the submandibular region is very important because of the possibility of sacrificing the hypoglossal nerve during surgery under the incorrect impression of a salivary gland tumor. Therefore, we report a case of hypoglossal nerve neurilemmoma occurring in the submandibular area with a review of the literature focusing on preoperative differential diagnosis.

Olfactory stimulation by vanillin prevents apnea in premature newborn infants

Apnea is one of the most common problems in premature newborns. The present study aimed to determine the effect of olfactory stimulation by vanillin on prevention of apnea in premature newborns. In this randomized controlled trial, 36 premature newborns with the postnatal age of 2 days and weight under 2500 grams referred to the hospitals affiliated to Shiraz University of Medical Sciences, were selected through simple random sampling and allocated into control and experimental groups. The experimental group received olfactory stimulation by saturated vanillin solution, while the control group received no interventions. The newborns of both groups were continuously monitored for presence/absence of apnea and number of episodes of apnea as well as arterial blood oxygen saturation and heart rate for 5 days. The data were analyzed by independent Student t-test and repeat measure ANCOVA. The presence of apnea revealed to be significantly different between the two groups in the first, second, and fourth day of the study [P<0.05]. The number of episodes of apnea during five days was also significantly different between the study groups [t=8.32, P<0.05]. Using olfactory stimulation by vanillin caused a 3.1-fold decrease in apnea and the effect size was 0.72. Moreover, the two groups were significantly different regarding the arterial blood oxygen and heart rate during the study period [P<0.05]. This study indicated the beneficial effect of saturated vanillin solution on apnea; therefore, it may be used for prevention and treatment of apnea in premature infants. Further studies are needed to improve evidence-based practice in this regard

A Clinical Analysis on Schwannoma in Head and Neck / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Neurogenic tumors in the head and neck are relatively rare and constitute around 0.5% of all head and neck tumors. Schwannoma, among neurogenic tumors, is a benign tumor originating from the spinal nerve root, peripheral nerve and all kinds of cranial nerves except the optic nerve and olfactory nerve. By presenting a series of head and neck schwannomas treated during a fifteen-year period, we aimed to analyze the clinical features, diagnosis, treatment and prognosis of schwannomas retrospectively. SUBJECTS AND METHOD: We retrospectively reviewed and analyzed clinical records of 34 patients with head and neck schwannomas who were treated surgically at the University Hospital from January, 1995 to January, 2010. RESULTS: We found 34 cases of schwannoma in the head and neck. Among the patients, 14 were males and 20 were females. The most common age group was the 60's while the most common site was the parapharyngeal space. The most common presenting symptom was palpable neck mass and the mean duration of symptoms was 41.6 months. The most common nerve of origin was the cervical plexus (29.4%). Preoperative diagnostic tools were FNA, CT and MRI. All cases were treated surgically and the most common postoperative complication was both transient and permanent voice changes. The mean follow-up period was 18.3 months and recurrence was not found during this period. CONCLUSION: Thirty-four cases of schwannoma in the head and neck were presented with respect to their clinical features.

Combined transplantation of neural stem cells and olfactory ensheathing cells improves the motor function of rats with intracerebral hemorrhage / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effects of combined transplantation of neural stem cells (NSC) and olfactory ensheathing cells (OEC) on the motor function of rats with intracerebral hemorrhage.</p><p><b>METHODS</b>In three days after a rat model of caudate nucleus hemorrhage was established, NSCs and OEC, NSC, OEC (from embryos of Wistar rats) or normal saline were injected into hematomas of rats in combined transplantation group, NSC group, OEC group, and control group, respectively. Damage of neural function was scored before and in 3, 7, 14, 30 days after operation. Tissue after transplantation was observed by immunocytochemistry staining.</p><p><b>RESULTS</b>The scores for the NSC, OEC and co-transplantation groups were significantly lower in 14 and 30 days after operation than in 3 days after operation (P < 0.05). The scores for the NSC and OEC groups were significantly lower than those for the control group only in 30 days after operation (P < 0.05), while the difference for the NSC-OEC group was significant in 14 days after operation (P < 0.05). Immunocytochemistry staining revealed that the transplanted OEC and NSC could survive, migrate and differentiate into neurons, astrocytes, and oligodendrocytes. The number of neural precursor cells was greater in the NSC and combined transplantation groups than in the control group. The number of neurons differentiated from NSC was significantly greater in the co-transplantation group than in the NSC group.</p><p><b>CONCLUSION</b>Co-transplantation of NSC and OEC can promote the repair of injured tissue and improve the motor function of rats with intracerebral hemorrhage.</p>

Olfactory ensheathing cells promote the survival of newborn rat spiral ganglion cells in vitro / 生理学报

The objective of this study is to explore whether olfactory ensheathing cells (OECs) can promote the survival of newborn rat spiral ganglion cells (SGCs) and the underlying possible mechanisms. Co-culture of OECs from adult rats with SGCs from newborn rat cochlea was established and single culture of SGCs acted as control. OECs were obtained and purified based on their special rate of attachment which was different from the other harvested cell types during culture. OECs and SGCs were immunocytochemically characterized and confirmed by expression of low-affinity nerve growth factor receptor p75 or positive label of neuron-specific betaIII-tubulin. To investigate the mechanisms of the role of OECs in survival of SGCs, brain derived neurotrophic factor (BDNF) and anti-BDNF antibody (IgY) were added into the media of the co-cultures respectively, and the surviving SGCs were examined after treatment. Single layer of OECs (92% pure) was seen seven days after plating. Surviving SGCs, which extended their primary neurites, were found on the surface of the layer in the co-cultures. When OECs and SGCs were co-cultured, the number of surviving SGCs was significantly greater than that in the single culture (P<0.01). Nine days after culture, there was even no change in the number of surviving SGCs in the co-culture while the number reduced to almost zero in the single culture. In comparison with co-culture without treatment, addition of BDNF (500 pg/mL) into the media had no obvious promoting effect on the survival of SGCs. The number of surviving SGCs reduced significantly when anti-BDNF antibody was applied into the media of co-cultures (P<0.01). These results suggest that OECs can promote the survival of SGCs when they are co-cultured in vitro. BDNF released from OECs, as one of the survival factors, plays an important role in the survival of SGCs.

A Case of Multiple Hypoglossal Neurilemmomas in the Submandibular Space / 대한이비인후과학회지

Neurilemmoma is a benign tumor which is known to originate from the myelin-producing Schwann cells of the spinal nerve root, peripheral nerve and all kinds of cranial nerves except the optic nerve and olfactory nerve. Approximately, 25% to 40% of all neurilemmomas are found in the neural structures of the head and neck. Neurilemmoma of the 12th cranial nerve is rare ; multiple neurilemmoma is even more rare. Recently, the authors experienced a case of multiple (x3) hypoglossal neurilemmoma in the submandibular space. The tumor was removed completely and verified histopathologically as neurilemmoma.

Immunohistochemical Analysis of Calretinin and Parvalbumin in the Goat Main Olfactory Bulb / 대한해부학회지

The distributions of calretinin (CR)- and parvalbumin (PV)-immunoreactive neurons in the main olfactory bulb (MOB) of the goat were examined in this study. As in other animals, the goat MOB has a characteristic laminar structure with laminar types and distribution patterns in each layer. CR-immunoreaction was observed in all layers of the MOB, except for the olfactory nerve layer. Most of CR-immunoreactive neurons were observed in the glomerular and granule cell layers. Relatively small number of CR-immunoreactive neurons was detected in other layers. These CR-immunoreactive neurons were interneurons. PV-immunoreaction was detected in all layers. In contrast to CR, olfactory nerve bundles were immunostained with PV. Most of PV-immunoreactive neurons were distributed in the glomerular and granule cell layers. PV-immunoreactive neurons were interneurons. This result suggests that CR and PV may play important roles in the olfactory signal modulation through interneurons in the goat MOB.