Expresión de proteínas ligantes de calcio durante la ontogenia del Sistema Nervioso Central de teleósteos

[ES] Hemos estudiado la distribución de tres proteínas ligantes de calcio, parvalbumina, calbindina d-28k, y calretinina, durante el desarrollo del sistema nervioso central de la trucha arco iris. Las tres proteínas se expresan en poblaciones celulares específicas durante la ontogenia. Calbindina d-28k aparece en diferentes poblaciones gliales. Calretinina y parvalbumina son marcadores neuronales, si bien parvalbumina aparece además en ependimocitos y oligodendrocitos en los estadios más avanzados del desarrollo. Calretinina y calbindina d-28k se expresan desde estadios embrionarios, mientras que parvalbumina lo hace después de la eclosión. Hemos detectado expresión transitoria de calretinina en la habénula, el techo óptico y el núcleo interpeduncular, fenómeno que no se produce ni con parvalbumina ni con calbindina d-28k. El orden de aparición de las tres proteínas durante el desarrollo del sistema nervioso central de la trucha arco iris es el mismo que el descrito previamente en mamiferos: en primer lugar la calretinina, a continuación la calbindina d-28k, y por último la parvalbumina

The effects of nicotine on cone and rod b-wave responses in larval zebrafish

Acetylcholine is present in and released from starburst amacrine cells in the inner plexiform layer (INL), but its role in retinal function except, perhaps, in early development, is unclear. Nicotinic acetylcholine receptors are thought to be present on ganglion, amacrine and bipolar cells processes in the IPL, and it is known that acetylcholine increases the spontaneous and light-evoked responses of retinal ganglion cells. The effects of acetylcholine on bipolar cells is not known, and here we report the effects of nicotine on the b-wave of the ERG in larval zebrafish. The b-wave originates mainly from ON-bipolar cells and in the larval zebrafish retina is cone-dominated. Only small rod responses can be elicited with dim lights in wild-type larval zebrafish retinas but rod responses can be recorded over a range of intensities in a mutant (nof) fish that has no cone function. We find that nicotine strongly enhances cone-driven b-wave response amplitudes but depresses rod driven b-wave response amplitudes without,however, affecting rod or cone driven b-wave light sensitivity

Transient expression of calretinin in the trout habenulo-interpeduncular system during development

Calcium-binding proteins control calcium homeostasis during neural development. The expression of one of these proteins, calretinin (CR), was monitored by immunohistochemistry in the developing habenulo-interpeduncular system of the rainbow trout, a conserved region of the brain along vertebrate phylogeny that undergoes a neurochemical reorganization in late development. No CR-immunoreactivity was observed in the habenulo-interpeduncular system during the embryonic development. CRimmunolabeling appeared in newly hatched fry, and during the fry development the number of CR-immunostained elements increased progressively. During the juvenile stages (from 30 days post-hatching onwards) a gradual decrease in the number of CRimmunostained cells occurred, until its complete disappearance in adults. These variations in CR expression may represent variable calcium-buffering needs during different developmental stages

Characterisation of neuronal and glial populations of the visual system during zebrafish lifespan

[EN] During visual system morphogenesis, several cell populations arise at different time points correlating with the expression of specific molecular markers We have analysed the distribution pattern of three molecular markers (zn-1, calretinin and glial fibrillary acidic protein) which are involved in the development of zebrafish retina and optic tectum. Zn-1 is a neural antigen expressed in the developing zebrafish central nervous system. Calretinin is the first calcium-binding protein expressed in the central nervous system of vertebrates and it is widely distributed in different neuronal populations of vertebrate retina, being a valuable marker for its early and late development. Glial fibrillary acidic protein (GFAP), which is an astroglial marker, is a useful tool for characterising the glial environment in which the optic axons develop. We describe the expression profile changes in these three markers throughout the zebrafish lifespan with special attention to ganglion cells and their projections. Zn-1 is expressed in the first postmitotic ganglion cells of the retina. Calretinin is observed in the ganglion and amacrine cells of the retina in neurons of different tectal bands and in axons of retinofugal projections. GFAP is localised in the endfeet of Müller cells and in radial processes of the optic tectum after hatching. A transient expression of GFAP in the optic nerve, coinciding with the arrival of the first calretinin-immunoreactive optic axons, is observed. As axonal growth occurs in these regions of the zebrafish visual pathway (retina and optic tectum)throughout the lifespan, a relationship between GFAP expression and the correct arrangement of the first optic axons may exist. In conclusion we provide valuable neuroanatomical data about the best characterised sensorial pathway to be used in further studies such as teratology and toxicology

Laboratorio virtual de histología

Memoria ID-0057. Ayudas de la Universidad de Salamanca para la innovación docente 2008-2009

Ensayos formativos autoevaluables en asignaturas del área Biología Celular

Memoria ID12-0146. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2012-2013

Desarrollo de prácticas con realidad aumentada para las asignaturas del área de Biología Celular

Memoria ID-138. Ayudas de la Universidad de Salamanca para la innovación docente, curso 2019-2020.[ES]El objetivo final del presente proyecto de innovación docente ha sido poner a punto la realidad aumentada (RA) mediante la utilización de imágenes y hologramas enlazados al sistema Merge Cube para que el alumno pueda analizar estructuras en 3D de los diferentes temas del Área de Biología celula

Expression of ZFOR1, a delta-opioid receptor, in the central nervous system of the zebrafish (Danio rerio)

Opioid receptors, besides mediating the effects of analgesic compounds, are involved in drug addiction. Although a large amount of work has been done studying these receptors in mammals, little information has been obtained from non-mammalian vertebrates. We have studied the regional distribution in the central nervous system (CNS) of the zebrafish of the recently cloned delta opioid receptor homologue ZFOR1 using non-radioactive in situ hybridization. Our findings show that different nuclei within the main subdivisions of the brain displayed specific mRNA signal. The expression is widespread throughout the brain, but only specific cells within each nucleus displayed ZFOR1. Stained cells were abundant in the telencephalon, both in the olfactory bulb and telencephalic hemispheres; and in the diencephalon, where expression was observed in all the different subdivisions. In the mesencephalon, expression of ZFOR1 was abundant in the periventricular layer of the optic tectum. In the cerebellum, expression of ZFOR1 was detected in valvula cerebelli, corpus cerebelli and lobus vestibulolateralis in both granule and Purkinje cells. In the myelencephalon, cells expressing ZFOR1 were also distributed in the octavolateralis area, the reticular formation and the raphe nuclei, among others. Also, ZFOR1 was detected in cells of the dorsal and ventral horn of the spinal cord. This work presents the first detailed distribution of a delta opioid receptor in the CNS of zebrafish. Distribution of ZFOR1 expression is compared with that of the delta opioid receptor described in mammals

Parvalbumin immunoreactivity during the development of the cerebellum of the rainbow trout

The distribution of parvalbumin immunoreactivity in the developing cerebellum ofthe rainbow trout was studied by using a specific monoclonal antibody and the avidin-biotin peroxidase method. Parvalbumin immunoreactivity was absent during the embryonic development of the cerebellum. The first immunoreactive elements, identified by their localization and posterior morphological evolution as immature Purkinje cells, appeared at 6 days posthatching in the presumptive corpus cerebelli and lobus vestibulolateralis. The labeling extended throughout the cerebellum following a caudorostral gradient, and in 21 days alevins, parvalbumin immunoreactive Purkinje cells were also observed in the valvula cerebelli. The appearance of PV-immunostaining in the Purkinje cells was not simultaneous; the labeling was observed initially in the cell body, extending gradually to the dendritic branches and finally to the axon. From one year onwards, parvalbumin immunoreactive terminal puncta from the Purkinje cell axons were observed surrounding the cell bodies of eurydendroid cells, that were parvalbumin immunonegative in all developmental stages studied. The spatio-temporal pattern of parvalbumin immunoreactivity in the rainbow trout cerebellum is different to previous observations in the cerebellum of amniotes

Neurocalcin immunoreactivity in the rato accessory olfactory bulb

The distribution and morphology of neurocalcin-immunopositive neurons have been studied in the rat accessory olfactory bulb. Different subsets of neurons displaying neurocalcin-immunoreactivity were found in the glomerular layer, the external plexiform layer and the internal plexiform layer. The most abundant staining was detected in the glomerular layer where neurocalcin-immunoreactive periglomerular cells and external tufted cells were observed in the lateral glomeruli, whereas the central region of this layer was practically devoid of immunopositive neurons. In the external plexiform layer, medial tufted cells and Van Gehuchten cells displayed neurocalcin-immunoreactivity. In the internal plexiform layer, interneurons classified as horizontal cells and vertical cells of Cajal were neurocalcin-immunostained. The staining pattern for neurocalcin in the accessory olfactory bulb showed similarities with the immunostaining described in this brain region for another EF-hand calcium binding protein, calbindin D-28k. However, after double immunohistochemical labeling, colocalization of both proteins in the same neuron was not observed, reflecting a biochemical heterogeneity within morphologically homogeneous neuronal groups