Immunohistochemical Evaluation of Calretinin in Ameloblastoma, Odontogenic keratocyst and Dentigerous Cyst

Background: Calretinin plays an important role in calcium signalling and naturally expressed in nervous tissues. Various stud- ies suggest that calretinin may involve in amelogenesis. Calretinin also seems to have role in tumorigenesis since it regulates apoptosis. Aim: To find out whether there is any variation in expression of calretinin in Ameloblastoma, Odontogenic keratocyst and Dentigerous cyst. Materials & Methods: A total of 50 samples each from Ameloblastoma, odontogenic keratocyst and Dentigerous cyst were retrospectively studied. The immunohistochemical expression of calretinin was assessed by using calretinin antibody. Results: Chi square test was used to compare categorical parameters between groups. Kruskal Wallis Test and Mann-Whitney U Test were carried out to compare quantitative parameters among the groups. Statistically, significant values were obtained when comparing the immunohistochemical expression of calretinin in various odontogenic lesions studied and it was highest in ameloblastoma followed by OKC. None of the cases of dentigerous cyst were immunopositive for calretinin. Conclusion: There was statistically significant variation in the expression of calretinin among ameloblastoma, OKC and dentig- erous cyst and it contributes to the aggressiveness of those lesions.

Revealing the Precise Role of Calretinin Neurons in Epilepsy: We Are on the Way / 神经科学通报·英文版

Epilepsy is a common neurological disorder characterized by hyperexcitability in the brain. Its pathogenesis is classically associated with an imbalance of excitatory and inhibitory neurons. Calretinin (CR) is one of the three major types of calcium-binding proteins present in inhibitory GABAergic neurons. The functions of CR and its role in neural excitability are still unknown. Recent data suggest that CR neurons have diverse neurotransmitters, morphologies, distributions, and functions in different brain regions across various species. Notably, CR neurons in the hippocampus, amygdala, neocortex, and thalamus are extremely susceptible to excitotoxicity in the epileptic brain, but the causal relationship is unknown. In this review, we focus on the heterogeneous functions of CR neurons in different brain regions and their relationship with neural excitability and epilepsy. Importantly, we provide perspectives on future investigations of the role of CR neurons in epilepsy.

Immunohistochemical distribution of calcium binding proteins in the cochlear nuclear complex of circling mice / Distribución inmunohistoquímica de proteínas de unión a calcio en el complejo nuclear coclear de ratones circulantes

SUMMARY: The term "circling mouse" refers to an animal model of deafness, in which the mouse exhibits circling, head tossing, and hyperactivity, with pathological features including degenerated spiral ganglion cells in the cochlea, and the loss of the organ of Corti. The cochlear nuclear (CN) complex, a part of the auditory brain circuit, is essential to process both ascending and descending auditory information. Considering calcium's (Ca2+) importance in homeostasis of numerous biological processes, hearing loss by cochlear damage, either by ablation or genetic defect, could cause changes in the Ca2+ concentration that might trigger functional and structural alterations in the auditory circuit. However, little is known about the correlation of the central nervous system (CNS) pathology in circling mice, especially of the auditory pathway circuit and Ca2+ changes. This present study investigates the distribution of Ca2+- binding proteins (CaBPs), calbindin D-28k (CB), parvalbumin (PV), and calretinin (CR) by using a free floating immunohistochemical method inthe CN of the wild-type mouse (+/+), the heterozygous mouse (+/cir), and the homozygous (cir/cir) mouse. CaBPs are well known to be an important factor that regulates Ca2+ concentrations. Compared with the dorsal and ventral cochlear nuclei of +/+ and +/ cirmice, prominent decreases of CaBPs' immunoreactivity (IR) in cir/cirmice were observed in the somas, as well as in the neuropil. The present study reportson the overall distribution and changes in the immunoreactivity of CaBPs in the CN of cir/cirmice because ofa hearing defect. This data might be helpful to morphologically elucidate CNS disorders and their relation to CaBPs immunoreactivity related to hearing defects.

RESUMEN: El término "ratón circulante" se refiere a un modelo animal con sordera, en el que el ratón exhibe hiperactividad, movimientos circulares y movimientos de la cabeza, con características patológicas que incluyen células ganglionares espirales degeneradas en la cóclea, un canal de Rosenthal vacío y la pérdida del órgano de Corti. El complejo nuclear coclear (CN), una parte del circuito cerebral auditivo, es esencial para procesar la información auditiva tanto ascendente como descendente. Considerando la importancia del calcio (Ca2+) en la homeostasis de numerosos procesos biológicos, la hipoacusia por daño coclear, por ablación o por defecto genético, podría provocar cambios en la concentración de Ca2+que pueden desencadenar alteraciones funcionales y estructurales en el circuitoauditivo. Sin embargo, existe poca información de la correlación de la patología del sistema nervioso central (SNC) en ratones circulantes, especialmente del circuito de la víaauditiva y los cambios de Ca2+. Este estudio nvestiga la distribución de proteínas de unión a Ca2+ (CaBP), calbindina D-28k (CB), parvalbúmina (PV) y calretinina (CR) mediante el uso de un método inmunohistoquímico de flotaciónlibre en el CN del ratón de tiposalvaje (+/+), el ratón heterocigoto (+/cir) y el ratón homocigoto (cir/cir). Se sabe que los CaBP son un factor importante que regula las concentraciones de Ca2+. En comparación con los núcleos cocleares dorsal y ventral de los ratones +/+ y +/ cir, se observaron disminuciones prominentes de la inmunorreactividad (IR) de CaBPs en los ratonescir/cir en los somas, asícomo en el neuropilo. El presente estudio informa sobre la distribución general y los cambios en la inmunorreactividad de CaBP en el CN de ratones cir/cir debido a un defecto auditivo. Estos datos podrían ser útiles para dilucidar morfológicamente los trastornos del SNC y su relación con la inmunorreactividad de CaBP relacionada con los defectosauditivos.

Calretinin expression in molecular subtypes of invasive carcinoma breast

Background: Breast cancer is a leading cause of cancer death  in women worldwide. Breast carcinoma is currently managed by assessing clinicopathological features. Elucidation of molecular mechanisms of pathogenesis of breast carcinoma  may lead to the development of new targeted therapies, particularly in triple negative cancers. Literature shows a few studies on the expression of calretinin  in breast carcinoma particularly in basal like type and its prognostic significance.  In this study, authors are trying  to assess the expression of  a new marker calretinin in different molecular subtypes of invasive carcinoma breast.Methods: This study was done in  107 cases of invasive carcinoma breast specimens received in  Department of Pathology, Government Medical college, Kottayam from December  2017 to May 2019.Results: Among the molecular subtypes, Basal like tumours showed 68.4% of cases with high level and 31.6% of cases with low level calretinin expression which is comparable with the study by Farrag et al. All the other molecular subgroups showed predominantly low level of calretinin expression.Conclusions: Different molecular subtypes of invasive carcinoma breast showed varied calretinin expression. High level calretinin expression was significantly associated with grade 3 (p value = 0.002), ER negativity (p = 0.004), PR negativity (p = 0.018)  and Basal like molecular subtype (p : <0.001). This suggests that calretinin might play a role in pathogenesis of basal like breast carcinomas.

A Rare Case of Sinonasal Ameloblastoma with Immunohistochemistry.

Introduction: Ameloblastoma is benign locally aggressivedentine epithelial tumor. Mandible and maxilla are commonsites of involvement. Calretinin is specific marker and usefulto differentiate ameloblastoma from Keratocystic odontogenictumor. The rarity of site and presentation of lesion makes usreport this case.Case report: 46 year old female had recurrent nasalblockage. Polyps in right nostrils were seen on Rhinoscopy.Polypectomy was done for suspected antrochoanal polyps.Ameloblastoma was diagnosed on histopathology andconfirmed by Immunohistochemistry with Cytokeratin,Calretinin and WT1.Conclusion: Preoperative diagnosis by biopsy in unilateralnasal masses should be carried out to expect the unexpected.Immunohistohemistry should be performed in cases havingrare site to confirm the diagnosis.

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.

Differential Expression of Ca²⁺-buffering Protein Calretinin in Cochlear Afferent Fibers: A Possible Link to Vulnerability to Traumatic Noise

The synaptic contacts of cochlear afferent fibers (CAFs) with inner hair cells (IHCs) are spatially segregated according to their firing properties. CAFs also exhibit spatially segregated vulnerabilities to noise. The CAF fibers contacting the modiolar side of IHCs tend to be more vulnerable. Noise vulnerability is thought to be due to the absence of neuroprotective mechanisms in the modiolar side contacting CAFs. In this study, we investigated whether the expression of neuroprotective Ca²⁺-buffering proteins is spatially segregated in CAFs. The expression patterns of calretinin, parvalbumin, and calbindin were examined in rat CAFs using immunolabeling. Calretinin-rich fibers, which made up ~50% of the neurofilament (NF)-positive fibers, took the pillar side course and contacted all IHC sides. NF-positive and calretinin-poor fibers took the modiolar side pathway and contacted the modiolar side of IHCs. Both fiber categories juxtaposed the C-terminal binding protein 2 (CtBP2) puncta and were contacted by synaptophysin puncta. These results indicated that the calretinin-poor fibers, like the calretinin-rich ones, were afferent fibers and probably formed functional efferent synapses. However, the other Ca²⁺-buffering proteins did not exhibit CAF subgroup specificity. Most CAFs near IHCs were parvalbumin-positive. Only the pillar-side half of parvalbumin-positive fibers coexpressed calretinin. Calbindin was not detected in any nerve fibers near IHCs. Taken together, of the Ca²⁺-buffering proteins examined, only calretinin exhibited spatial segregation at IHC-CAF synapses. The absence of calretinin in modiolar-side CAFs might be related to the noise vulnerability of the fibers.

Changes of Auditory Brainstem Response and Expression of Parvalbumin , Calretinin and Calbindin D-28K in the Inferior Colliculus in Rats Following Noise Exposure / 听力学及言语疾病杂志

Objective To study the possible mechanism of hearing impairment after noise exposure .Methods Adult SD rats (n=14) were monaurally exposed to a loud noise (16 kHz ,one octave band pass (116 dB SPL)) for 1-hour ,or left as non-exposed controls (n=8) .The ABR was measured before and on the 7th day following unilateral noise exposure .All the Animals were euthanased at 7th day following acoustic trauma .We used Western blots to quantify protein levels of PV ,CR and CB in the inferior colliculus .Results The auditory thresholds in 8 , 12 ,16 ,20 ,24 ,and 32 kHz of all the ears exposed to noise showed a significant increase (P<0 .001) .Compared to the sham -exposed controls ,noise-exposed animals had significantly higher levels of PV and CR and lower levels of CB in both the ipsilateral and contralateral IC than controls (P<0 .05) .Respectively ,all the noise-exposed ani-mals had higher levels of PV and CR in the ipsilateral IC than ipsilateral side (P<0 .05) .Conclusion These studies display a significant threshold shift and changes on the expressions of PV ,CR and CB in IC following acoustic trau-ma ,which may be related to noise deafness ,tinnitus and other series of auditory dysfunction .

The distribution of calbindin-D28k, parvalbumin, and calretinin immunoreactivity in the inferior colliculus of circling mouse / 대한해부학회지

The circling mice with tmie gene mutation are known as an animal deafness model, which showed hyperactive circling movement. Recently, the reinvestigation of circling mouse was performed to check the inner ear pathology as a main lesion of early hearing loss. In this trial, the inner ear organs were not so damaged to cause the hearing deficit of circling (cir/cir) mouse at 18 postnatal day (P18) though auditory brainstem response data indicated hearing loss of cir/cir mice at P18. Thus, another mechanism may be correlated with the early hearing loss of cir/cir mice at P18. Hearing loss in the early life can disrupt the ascending and descending information to inferior colliculus (IC) as integration site. There were many reports that hearing loss could result in the changes in Ca²⁺ concentration by either cochlear ablation or genetic defect. However, little was known to be reported about the correlation between the pathology of IC and Ca²⁺ changes in circling mice. Therefore, the present study investigated the distribution of calcium-binding proteins (CaBPs), calbindin-D28k, parvalbumin, and calretinin immunoreactivity (IR) in the IC to compare among wild-type (+/+), heterozygous (+/cir), and homozygous (cir/cir) mice by immunohistochemistry. The decreases of CaBPs IR in cir/cir were statistically significant in the neurons as well as neuropil of IC. Thus, this study proposed overall distributional alteration of CaBPs IR in the IC caused by early hearing defect and might be helpful to elucidate the pathology of central auditory disorder related with Ca²⁺ metabolism.

Differential expression and clinical significance of calretinin in total colonic aganglionosis / 中华病理学杂志

Objective@#To evaluate the differential calretinin immunostaining in different segments of total colonic aganglionosis and its utility in the diagnosis.@*Methods@#Nine specimens including ileum and colon segments were obtained from 9 patients with total colonic aganglionosis (TCA), from 2010 to 2016 year, in Wuhan Children′s Hospital, Tongji Medical College, Huazhong University of Science and Technology. Another 9 ganglionic specimens including the same segments from patients with non-Hirschsprung disease (non-HD) patients were collected as control. All cases were immunostained with calretinin. The patterns of calretinin immunostaining were observed, and morphometric analysis of each sample was performed by image analysis program (Image-Pro-Plus). The mean absorbance was evaluated by calculating the areas of the lamina propria occupied by the positively stained area of the calretinin at high power field.@*Results@#The same pattern of calretinin immunostaining was seen in ganglionic ileum and ganglionic colon segments, with staining seen in intrinsic nerves fibers (INF), and in granular aggregates in the lamina propria and muscularis mucosae. There was no significant difference in the numbers of calretinin-positive INF from the ganglionic segments. In contrast, the number of calretinin-positive INF and granular aggregates in aganglionic segments were significantly lower than those in the ganglionic group (P<0.01). In the ileum transitional zone, scattered calretinin staining was observed, and the amount of calretinin-positive INF was significantly lower than those in the proximal segment of ganlionic ileum (P<0.01).@*Conclusions@#Since there is significant different expression of calretinin among the different segments from TCA, calretinin immunostaining has potential value in detecting TCA. It could be an important adjunctive method in detecting TCA in the future.

Calretinin immunohistochemistry versus improvised rapid Acetylcholinesterase histochemistry in the evaluation of colorectal biopsies for Hirschsprung disease.

Background: Acetylcholinesterase (AChE) histochemistry on rectal mucosal biopsies accurately diagnoses Hirschsprung disease (HD), but is not widely employed as it requires special tissue handling and pathologist expertise. Calretinin immunohistochemistry (IHC) has been reported to be comparable to AChE staining with the loss of expression correlating with aganglionosis. Aim: The aim was to evaluate calretinin IHC as a primary diagnostic tool in comparison to the improvised rapid AChE technique in the diagnosis of HD. Materials and Methods: A total of 74 rectal biopsies (18 fresh frozen - 18 cases, 56 formalin fixed - 33 cases) from 51 cases of suspect HD were evaluated with hematoxylin and eosin/AChE/Calretinin. Ten biopsies each from ganglionated and aganglionated segments served as positive and negative controls. Ileal (3), appendiceal (3) and ring bowel (2) biopsies were also included. Two pathologists blinded to the clinical details evaluated the histomorphology with AChE and calretinin. Observations were statistically analyzed and Cohen’s κ coefficient employed to assess agreement between two pathologists and calretinin and the AChE. Results: The study confirmed HD in 26 and non-HD in 25 cases. There were 7 neonates, 5 low level biopsies and 14 “inadequate” biopsies. The results of calretinin were comparable with AChE with a statistically significant measure of agreement of κ = 0.973 between the two. One false-positive case of HD was noted with calretinin. The advantages and disadvantages of calretinin versus AChE are discussed. Conclusion: Calretinin is a reliable single immune marker for ruling out HD by its specific positive mucosal staining of formalin fixed rectal biopsy. The improvised AChE staining remains indispensable to confirm HD on fresh biopsies and thus, along with calretinin IHC maximizes the diagnostic accuracy of HD in difficult cases.

Immunohistochemical study on the expression of calcium binding proteins (calbindin-D28k, calretinin, and parvalbumin) in the cerebellum of the nNOS knock-out(-/-) mice / 대한해부학회지

Nitric Oxide (NO) actively participates in the regulation of neuronal intracellular Ca2+ levels by modulating the activity of various channels and receptors. To test the possibility that modulation of Ca2+ buffer protein expression level by NO participates in this regulatory effect, we examined expression of calbindin-D28k, calretinin, and parvalbumin in the cerebellum of neuronal NO synthase knock-out (nNOS(-/-)) mice using immunohistochemistry. We observed that in the cerebellar cortex of the nNOS(-/-) mice, expression of calbindin-D28k and parvalbumin were significantly increased while expression of calretinin was significantly decreased. These results suggest another mechanism by which NO can participate in the regulation of Ca2+ homeostasis.

Changes in transcript and protein levels of calbindin D28k, calretinin and parvalbumin, and numbers of neuronal populations expressing these proteins in an ischemia model of rat retina / 대한해부학회지

Excessive calcium is thought to be a critical step in various neurodegenerative processes including ischemia. Calbindin D28k (CB), calretinin (CR), and parvalbumin (PV), members of the EF-hand calcium-binding protein family, are thought to play a neuroprotective role in various pathologic conditions by serving as a buffer against excessive calcium. The expression of CB, PV and CR in the ischemic rat retina induced by increasing intraocular pressure was investigated at the transcript and protein levels, by means of the quantitative real-time reverse transcription-polymerase chain reaction, western blot and immunohistochemistry. The transcript and protein levels of CB, which is strongly expressed in the horizontal cells in both normal and affected retinas, were not changed significantly and the number of CB-expressing horizontal cells remained unchanged throughout the experimental period 8 weeks after ischemia/reperfusion injury. At both the transcript and protein levels, however, CR, which is strongly expressed in several types of amacrine, ganglion, and displaced amacrine cells in both normal and affected retinas, was decreased. CR-expressing ganglion cell number was particularly decreased in ischemic retinas. Similar to the CR, PV transcript and protein levels, and PV-expressing AII amacrine cell number were decreased. Interestingly, in ischemic retinas PV was transiently expressed in putative cone bipolar cell types possibly those that connect with AII amacrine cells via gap junctions. These results suggest that these three calcium binding proteins may play different neuroprotective roles in ischemic insult by their ability to buffer calcium in the rat retina.

Changes in Calcium-binding Proteins in the Rat Hippocampus after Involuntary Treadmill Exercise / 대한해부학회지

In this study, we investigated the effects of treadmill exercise on hippocampal levels of calcium-binding proteins - calbindin D-28k (CB), calretinin (CR) and parvalbumin (PV) - using immunohistochemistry and Western blot analysis. At 6 weeks of age, male Wistar rats were put on a treadmill with or without running for 1 h/day/5 consecutive days at a pace of 22 m/min for a period of 5 weeks. In sedentary and exercise groups, CB immunoreaction was detected in granule cells of the dentate gyrus, mossy fibers, and CA1 pyramidal cells. In addition, CB immunoreaction was observed in interneurons of the CA1-3 region. Exercise significantly increased CB immunoreactivity in dentate granule cells, CA1 pyramidal cells and CA1-3 interneurons. CR immunoreaction was mainly observed in interneurons of the dentate gyrus and CA1-3 regions. Similar number of CR-immunoreactive neurons was observed in the exercise and sedentary groups. PV immunoreaction was detected in interneurons of the dentate gyrus and CA1-3 regions. PVimmunoreactive fibers were significantly increased in all regions of the hippocampus in the exercise group, as compared to the sedentary group. Similar to the immunohistochemical findings, protein levels of CB and PV were also increased in the exercise group compared to the sedentary group. These increases in CB and PV in the hippocampus may induce neuronal plasticity after treadmill exercise and may be related to the enhancement of synaptic plasticity in the hippocampus by exercise.

The Effect of 835 MHz Radiofrequency Radiation Exposure on the Immunohistochemical Distribution of Calbindin D28k and Calretinin in the Mouse Cerebellar Cortex / 체질인류학회지

Widespread use of mobile phones and subsequent electromagnetic field (EMF) exposure have raised crucial question of their possible biological effects on the nervous system. The study on the effect of radiofrequency(RF) radiation on the nervous system, however, did not precede enough to determine the biological hazard to brain. Until now, several studies have reported decreases in neuron number and neuronal damage in the cortex, hippocampus, and basal ganglia in the brains of animals exposed to RF radiation. However, there were few reports about the cerebellum, the main voluntary motor control center. In this regard, by using immunohistochemisty, current study intended to investigate the changes in the calbindin D28k (CB) and calretinin (CR)-immunoreactivity (IR) in the mouse cerebellar cortex after EMF exposure at 835 MHz for different exposure times and absorption rates, 1 h/day for 5 days at 1.6 W/kg, 1 h/day for 5 days at 4.0 W/kg, 5 h/day for 1 day at 1.6 W/kg, 5 h/day for 1 day at 4.0 W/kg, daily exposure for one month at 1.6 W/kg. Among groups, most prominent CB IR was observed in the Purkinje cell layer followed by molecular and granular layer. The highest CB IR was noted in 5 h/day for 1 day at 1.6 W/kg in the entire three layers while the lowest was noted in one month at 1.6 W/kg. Similarly CR IR was maximum in one month at 1.6 W/kg whilst the lowest was observed in 1 h/day for 5 days at 4.0 W/kg. EMF exposure for 5 days at 1.6 W/kg reduced CB-IR. The CR-IR was mainly localized in small cells in the granular layer, with maximum IR observed after one month exposure. Therefore, the present study suggest the possibility of alterations of calcium ion concentration, which play a role in maintaining metabolic homeostasis, in the cerebellum after long-term exposure to 835 MHz of RF radiation, which might lead to thedisruption of normal trait.

The Calretinin Immunoreactive Ganglion Cell Postsynaptic to the ON-Cholinergic Amacrine Cell in the Guinea Pig

PURPOSE: To demonstrate the characterization calretinin-immunoreactive displaced amacrine cells in the ganglion cell layer using immunohistochemistry and electron microscopy. METHODS: For immunohistochemistry, sections from guinea pig retina were incubated with mouse monoclonal antibody directed against calretinin. For double label studies, sections were incuated in mixture of mouse monoclonal anti-calretinin or rabbit polyclonal anti-calretinin with following antibodies: goat polyclonal anti-ChAT, rabbit polyclonal anti-GABA, mouse monoclonal anti-GABAA receptor alpha1, beta2/3. Sections were analyzed using Bio-rad Radiance Plus confocal scanning microscope. Stained sections from three guinea pig were observed with transmission electron microscope. RESULTS: Calretinin immunoreactivity was present in displaced amacrine cells and ganglion cells gaving rise to processes ramified in the inner part of the inner plexiform layer in stratum 4. The same stratum was also occupied by the dendrites of ON-cholinergic amacrine cells. Double-labeling demonstrated that dendrites and cell bodies of displaced amacrine cells colocalized with ON-cholinergic amacrine cells and dendrites of ganglion cells directly overlapped with dendrites of ON-cholinergic amacrine cells. The synaptic connectivity was identified by electron microscopy. Ganglion cell dendrites received synaptic input from ON-cholinergic amacrine cell. GABAA receptor beta2/3 subunit bands cofaciculates the dendrites of displaced amacrine cell and ganglion cell that are juxtapose to the alpha1 subunit of GABAA receptor. CONCLUSIONS: These results indicate that ON-cholinergic amacrine cells modulate calretinin-labeled ganglion cell via GABAA receptor beta2/3 in the guinea pig retina.

Immunohistochemical characterization of the chick marginal retina

The retina is a highly differentiated tissue with a complex layered structure that has been extensively characterized. However, most of the previous studies focused on the histology of the central retina while little is known about the cellular composition, organization and function of the marginal retina. Recent research has identified a subpopulation of multipotential progenitor cells in the marginal regions of the retina, closest to the ciliary body ("ciliary marginal zone"). These cells are capable of differentiation in response to an appropriate stimulus. Thus, it is possible that the structure and composition of the marginal retina are distinct from those of the central retina to accommodate the potential addition of newly formed neurons. To characterize the cellular profile of the chick marginal retina, we labeled it immunohistochemically for markers whose staining pattern is well established in the central retina: calbindin, calretinin, protein kinase C, and choline acetyltransferase. Calbindin was present at very low levels in the marginal retina putative photoreceptor layer. Calretinin-positive horizontal cells were also sparse close to the ciliary marginal zone. The bipolar cells in the marginal outer plexiform layer were positive for anti-protein kinase C antibodies, but the density of labeling was also decreased in relation to the central retina. In contrast, the marginal starburst cholinergic amacrine cell pattern was very similar to the central retina. From these data we conclude that the structure of the marginal retina is significantly different from that of the central retina. In particular, the expression of late retina markers in the marginal retina decreased in comparison to the central retina.

The Diagnostic Utility of Mesothelial Markers in Distinguishing between Reactive Mesothelial Cell and Adenocarcinoma Cells in Serous Effusions with Cytospin Preparation / 대한세포병리학회지

Evaluation of serous effusions can include immunocytochemical stains that differentiate reactive mesothelial cell from adenocarcinoma cell. Among several positive mesothelial cell markers, we used desmin, CK5/6, WT1 and calretinin all known to have high sensitivity and specificity as selective mesothelial cell markers. We studied smears obtained with cytospin from 15 malignant and eight benign effusions. The mesothelial cells were positively stained by desmin, CK5/6, WT1 and calretinin in 60.9%, 29.1%, 26.7% and 56.5%, respectively among 8 benign and 15 malignant effusions; the adenocarcinoma cells were positively stained 6.7%, 13.3%, 1.0% and 0.0%, respectively among 15 malignant effusions. The percentage of positively stained mesothelial cells were somewhat lower for all antibodies compared to the results of previous studies. This was likely due to the differences in preparation methods and fixatives among studies. In conclusion, the use of desmin and calretinin were more valuable than CK5/6 and WT1 for distinguishing between reactive mesothelial cell and adenocarcinoma cells in serous effusion; however, choice of the proper preparation methods and fixatives are also important

Immunohistochemical localization of calcium binding proteins and some neurotransmitters in myenteric plexus of goat stomach

To understand the neurochemical properties of the gastric myenteric plexus of ruminants, the expression patterns of calbindin D-28k (CB), calretinin (CR), substance P (SP) and calcitonin gene-related peptide (CGRP) were explored in the Korean native goat. In gastric myenteric plexus, CB and SP immunoreactivity were observed in round- or ovalshaped neurons. CR and CGRP immunoreactivity were detected only in the nerve fibers. This immunohistochemical localization of CB, CR, CGRP and SP in the myenteric plexus of the goat stomach exhibited species-specific patterns. These findings suggest that these substances may be directly or indirectly related to the gastric functions of the goat stomach.

Distribution of Calretinin-immunoreactive Unipolar Brush Cells in Ataxic Mutant Pogo Mice Cerebellum / 대한해부학회지

Unipolar brush cells (UBCs) are a class of putative interneurons found in the granular layer of mammalian cerebellum and dorsal cochlear nucleus. The unipolar brush cells (UBCs), as with granular cells, which receives afferent synaptic input from extrinsic mossy fiber and whose axons branch in the granular layer and establish a system of cortex-intrinsic mossy fibers, which synapse with granule cells and other UBCs. In general, UBCs have been identified most readily by their expression of the calcium-binding protein, calretinin. The purpose of this study was to provide information about UBCs distributions of the new ataxic animal model, pogo mouse cerebellum using anti-calretinin immunohistochemistry, immunofluorescence and its effect on calcium homeostasis. Through the examination of calretinin immunohistochemistry and immunofluorescence, we observed that many calretinin immunoreactive UBCs were distributed widely throughout the lobules IX and X of the granular layer of both group. But, we found the number of calretinin immunoreactive UBCs of ataxic pogo (pogo/pogo) mouse was decreased and distribution pattern was altered, compared to control mouse. This result also suggest that reduced calretinin expression may effect on cerebellar Ca2+/-homeostasis, and it may in turn, explain the impaired motor coordination found in the ataxic pogo mice.