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At least 19 recordsLinked to original sources
PubMed1987

Distribution of Calbindin-D28K 1 (CaBP) in the cerebral cortex and hippocampus of the epileptic (El) mouse.

The distribution of Calbindin-D28K (CaBP), a calcium-binding protein that binds Ca2+ with high affinity, was measured by radioimmunoassay in various cortical regions of the epileptic strain of mice El. The El strain, in which seizures are induced by repeated vestibular stimulation, had significantly lower levels of CaBP in the hippocampus and dorsal occipital cortical areas than the control CF-1 strain. Following induction of seizures in the El strain, a further decrease in CaBP levels was observed in the hippocampal formation and ventral temporal cortical regions, areas where paroxysmal activity is generated in this strain. Considering the role of CaBP as an intraneuronal calcium buffer, the present findings indicate that neuronal calcium regulation is genetically altered in the El strain and is further disturbed during the events that lead to induction of seizures.

Animals↗
PubMed1991

Molecular basis for co-operativity in Ca2+ binding to calbindin D9k. 1H nuclear magnetic resonance studies of (Cd2+)1-bovine calbindin D9k.

The molecular basis for the co-operativity in binding of calcium ions by bovine calbindin D9k has been addressed by carrying out a comparative analysis of the solution conformation and dynamics of the apo, half saturated and fully saturated species using two-dimensional 1H nuclear magnetic resonance spectroscopy. Since the half saturated calcium form of the protein is not significantly populated under equilibrium conditions due to the co-operativity in binding of calcium ions, the half saturated cadmium form of the protein has been substituted for the calcium form. To verify that cadmium forms of calbindin D9k represent viable models for the calcium-bound species, the fully saturated cadmium form has been prepared and compared to the calcium-saturated protein. Virtually complete 1H resonance assignments have been obtained for both the (Cd2+)1 and the (Cd2+)2 states. Secondary structure elements and the global folding pattern were determined from nuclear Overhauser effects, backbone spin-spin coupling constants and slowly exchanging amide protons. Comparisons of the half saturated protein with the apo and calcium-saturated forms of calbindin D9k show that all three structures are highly similar. However, a change in the structural and dynamic properties of the protein does occur upon binding of the first ion; the half saturated form is found to be more similar to the calcium-saturated form than to the apo form. These results have important implications concerning the molecular basis for the co-operativity, and suggest that entropic effects associated with the protein dynamics play an important role.

Amino Acid Sequence↗
PubMed1992

Calbindin-D28k in the basal ganglia of patients with parkinsonism.

An immunohistochemical study was carried out to investigate the topographic distribution of calbindin-D28k in the human basal ganglia and substantia nigra and its alterations in patients with idiopathic Parkinson's disease (PD), parkinsonism-dementia complex on Guam, progressive supranuclear palsy, and striatonigral degeneration. In normal control subjects, calbindin-D28k immunoreactivity was identified in the medium-sized neurons and neuropil of the matrix compartment of the striatum, the woolly fiber arrangements of the globus pallidus, and the fiber structures of the pars reticulata of the substantia nigra. Calbindin-D28k expression in the basal ganglia of patients with PD and parkinsonism-dementia on Guam was not different from that of control subjects, suggesting that the matrical output pathway is spared in these disorders. In contrast, its disruption is inferred from the observed disorganization of woolly fibers in the globus pallidus of patients with progressive supranuclear palsy and the reduced calbindin-D28k reactivity in the putaminal matrix and the pars reticulata of the substantia nigra of subjects with striatal degeneration. Thus, our results indicate that calbindin-D28k is a useful marker for the projection system from the matrix compartment and that its expression is modified in patients with progressive supranuclear palsy and striatal degeneration.

Aged↗
PubMed1986

Calcium-binding protein (28,000 Mr calbindin-D28k) in kidneys of the bullfrog Rana catesbeiana during metamorphosis.

A protein of approximately 28,000 relative molecular mass (Mr) cross-reacting with antiserum against the 28,000-Mr rat renal calcium-binding protein (calbindin-D28k) has been localized in the kidney of a salientian amphibian, Rana catesbeiana. Cells reactive for calbindin-D28k were found in the distal tubule at all stages of metamorphosis by the unlabeled antibody peroxidase-antiperoxidase technique. Adult kidneys appeared to have more calbindin-D28k-positive cells. The renal corpuscle, neck, and proximal tubule were negative. An immunoreactive 28,000-Mr band that comigrated with the band of calbindin-D28k was visualized by the immunoblot technique. The finding of the 28,000-Mr calbindin-D in the anamniotic kidney demonstrates that this calcium-binding protein (CaBP) is phylogenetically older than our previous studies of higher vertebrates had revealed (Rhoten et al., 1985). Although the function of calbindin-D28k in the distal nephron is unknown, this CaBP can now be presumed to have functional significance in the mesonephric as well as the metanephric kidney.

Animals↗
PubMed1988

An immunohistochemical study of the ontogeny of the horizontal cell in the rat retina using an antiserum against spot 35 protein, a novel Purkinje cell-specific protein, as a marker.

A sequence of morphological changes during the differentiation of retinal horizontal cells was studied by means of immunohistochemistry for spot 35 protein, a novel Purkinje cell-specific protein, in the rat retina. Spot 35-immunoreactive horizontal cell anlagen were first identified at embryonic day 18 (E18) in the outer zone of the neuroblastic cell layer as fusiform cells with slender inner and outer processes. As the development proceeded, the immunoreactive cells increased in number and intensity of the immunostaining, and the outer processes of the immunoreactive cells were often bifurcated close to their origin or at their periphery. At postnatal days 3 and 5 (P3 and P5), a regional difference in morphology of the immunoreactive horizontal cell anlagen was recognized: The immunoreactive cells near the ora serrata still assumed a bipolar shape, and those in the central portion of the retina had multiple processes. At P7 and P10, the immunoreactive cells in the periphery of the retina extended most of their outer processes in the plane of the retina, forming a network together with processes of adjacent immunoreactive horizontal cells. Their internally extending processes during these postnatal stages tended to be present in small numbers and to be short. At P14 all the immunoreactive horizontal cells extended their processes horizontally to form a tight bundle all the way along the outer plexiform layer. These findings indicate that spot 35 protein is a specific marker for the horizontal cells of the rat retina in the developmental process from their bipolar stage at E18 until reaching their mature configuration at P14.

Animals↗
PubMed1990

Cellular gene expression for calbindin-D28k in mouse kidney.

Gene expression for calbindin-D28k, the 28,000 relative molecular mass vitamin D-dependent calcium-binding protein, was measured in cells of the murine nephron by in situ hybridization on tissue sections (hybridization cytochemistry). Radiolabeled (35S-UTP), single-stranded RNA complementary to calbindin-D28k-mRNA (probe RNA) was prepared from linearized cDNA template and used for the hybridizations. Autoradiography was carried out and cellular levels of hybridization signal (silver grains) were quantified. After correction for background the concentration of silver grains was more than 350% greater in the distal tubule than in either the proximal tubule or the glomerulus. The relative cellular level of mRNA in the cytoplasm, as reflected in silver grains/cell, of the distal tubules with probe RNA was 3.4 times greater than that with control RNA. Cells of the distal tubule were the only apparent sites of specific hybridization with probe RNA. The presence of calbindin-D28k-mRNA in the distal tubule corresponded to the localization of calbindin-D28k by immunocytochemistry.

Animals↗
PubMed1990

Immunohistochemical localization of calbindins (28K and 9K) in the tissues of the baboon Papio ursinus.

An indirect immunoperoxidase procedure was used to detect the presence of calbindin-D28K and calbindin-D9K in the cerebellum, kidney, and duodenum of the baboon Papio ursinus. Antibodies to chick calbinding-D28K and to both rat and mouse calbindin-D9K were used. The cerebellum and kidney were shown to contain calbindin-D28K; the doudenum contained calbindin-D9K. In the cerebellum, positive staining was found in the Purkinje cells only; in the kidney, positive staining was found in the distal convoluted tubules, connecting tubules, and collecting tubules, extending deep into the medullary regions of the kidney. Staining in the duodenum was confined to the enterocytes of the villi, with no stain present in the crypt regions or goblet cells. Thus the baboon, a primate, contains the larger of the calbindins in both the cerebellum and kidney as does the human and monkey, but its distribution in the kidney is more generalized than that found in humans. The molecular weight of calbindin-D9K was found to be similar to that found in other animals. However, the calbindin-D28K from the baboon tissues appears to be slightly smaller than the protein found in other animals and may therefore be of similar size to the human calbindin-D28K (Mr 26,000).

Animals↗
PubMed1989

Ultrastructural localization of immunoreactive calbindin-D28k in the rat and monkey basal ganglia, including subcellular distribution with colloidal gold labeling.

Normal cellular function depends on the controlled flux of Ca++ within intracellular compartments and across the plasma membrane. Proteins that bind Ca++ are thought to contribute to the regulation of intracellular Ca++ and, perhaps more importantly, signal functional changes in cell activity. In the brain, calbindin-D28k is among a class of calcium-binding proteins that are widely and heterogeneously distributed in select populations of neurons, among them neostriatal cells, but whose function is largely unknown. In this study of the monkey and rat neostriatum and globus pallidus, calbindin-D28k was localized with immunoperoxidase and immunogold methods in order to identify striatal cell populations that contain this protein and the subcellular compartments in which it is likely to function. Light and electron microscopy showed intense and extensive labeling of immunoreactive calbindin-D28k in the cell bodies, dendrites, and spines of medium-sized neostriatal spiny neurons and in their axon terminals which end in the globus pallidus. More discrete labeling with a gold-conjugated second antibody showed that the predominant site of calbindin-D28k was the matrix of the cytoplasm. Gold label was also associated with the karyoplasm of spiny cells and with the neurofilaments and axoplasmic matrix of striatopallidal axons and terminals, respectively. Membranes were either sparsely labeled (endoplasmic reticulum, mitochondria) or devoid of gold particles (nuclear envelope and plasmalemma). Radioimmunoassays of striatal subcellular fractions supported the anatomical findings by indicating that the soluble fractions of neostriatal tissue homogenates contained most of the calbindin-D28k immunoreactivity and that washes from forebrain synaptosomes treated with Triton X-100 yielded high levels of immunoreactive calbindin-D28k. These findings show that immunoreactive calbindin-D28k is localized to spiny neurons of the striatopallidal pathway and are consistent with previous observations on subcellular localization in nonneuronal tissues. If, as recently speculated, calbindin-D28k regulates calcium concentrations in neostriatal spiny neurons, this feature may be particularly involved with the high density of glutamatergic inputs to these cells. More work is needed to determine whether calbindin-D28k, when complexed to Ca++ in neostriatal spiny cells, signals the activation of protein kinases, phosphorylation, and/or neurotransmitter release, as has been shown for other Ca++-binding proteins in mammalian tissues.

Animals↗
PubMed1990

Parvalbumin-containing GABAergic interneurons in the rat neostriatum.

Antibodies to the intracellular calcium binding protein parvalbumin were shown to label specifically a distinct group of neostriatal GABAergic neurons. These neurons corresponded to the intensely staining subclass of neostriatal GABAergic neurons that have previously been shown to be a class of aspiny interneurons in the neostriatum. The parvalbumin neurons were aspiny neurons with varicose dendrites distributed throughout the neostriatum in a pattern identical to the intensely stained GABA neurons, and both populations of neurons showed increased numbers in the lateral part of the neostriatum. Double labeling of single neurons with both the GABA and parvalbumin antisera showed that all parvalbumin neurons were positive for GABA, but some GABA labelled neurons were not immunoreactive for parvalbumin. These parvalbumin-negative GABAergic neurons were morphologically similar to the spiny projection neurons, which are GABAergic but usually are not so heavily stained. The relationship of the GABA-containing parvalbumin neurons to the striatal mosaic organization was determined by using immunocytochemistry for another calcium binding protein, calbindin D28K, to label the matrix compartment of the striatum. The distribution of parvalbumin-positive neurons relative to the calbindin-positive matrix and calbindin-poor patches was determined by using pairs of adjacent sections stained with the calbindin and parvalbumin antisera. This analysis showed that the somata of the parvalbumin neurons were present in both patch and matrix compartments, and their axons and dendrites crossed the boundaries between compartments. A quantitative analysis of the number of neurons in each compartment revealed that the neurons showed no preferential distribution in either compartment, but instead were present according to the area occupied by that compartment.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1991

Calcium-binding protein (calbindin-D28K) and parvalbumin immunocytochemistry in the normal and epileptic human hippocampus.

The calcium-binding proteins calbindin-D28K (CaBP) and parvalbumin (PV) were localized in the "normal" and "epileptic" human hippocampus to address the possible relationship between the expression of these constitutive cytosolic calcium-binding proteins and the resistance or selective vulnerability of different hippocampal neuron populations in temporal lobe epilepsy. Compared to rodents and a baboon (Papio papio), the pattern of CaBP-like immunoreactivity (LI) in the "normal" human hippocampus is unique. CaBP-LI is present in the dentate granule cells, neurons of the "resistant zone" (area CA2), and presumed interneurons of all regions. Unlike rodent and baboon CA1 pyramidal cells, human CA1 pyramidal cells appear to be devoid of CaBP-LI. Thus, the relatively resistant dentate granule cells and CA2 pyramidal cells are the only human hippocampal principal cells that contain CaBP-LI normally. As in lower mammals, PV-LI is present exclusively in interneurons of all human hippocampal subregions. CaBP- and PV-LI were localized in hippocampi surgically removed in the treatment of intractable temporal lobe epilepsy to determine whether surviving hippocampal cells were those that express these calcium-binding proteins. Hippocampi removed from patients with tumors or arteriovenous malformations that were associated with complex partial seizures arising from this region appeared relatively normal histologically. CaBP- and PV-LI in this patient group appeared similar to that seen in autopsy controls. Conversely, "cryptogenic" epileptics, who exhibit hippocampal sclerosis as the only lesion associated with the epilepsy, exhibited a preferential survival of hippocampal cells that were CaBP- or PV-immunoreactive. In the dentate hilus, which normally contains few CaBP-LI neurons, most of the few surviving hilar neurons were CaBP-immunoreactive. Their number and darkness of staining suggests that CaBP synthesis may be increased in cells that survive. Despite an obvious decrease of PV-LI specifically in the damaged parts of the sclerotic hippocampi, PV-immunoreactive interneurons were often among the few surviving cells. Nevertheless, large expanses of the surviving granule cell layer appeared to have lost the PV-immunoreactive axosomatic fiber plexus. These results reveal a unique and striking correlation between the human hippocampal cells that normally express these calcium-binding proteins and those that survive in the sclerotic epileptic hippocampus.

Adult↗
PubMed1991

Subpopulations of GABAergic neurons containing parvalbumin, calbindin D28k, and cholecystokinin in the rat hippocampus.

The possible coexistence of calbindin D28k with parvalbumin and of calbindin D28k with cholecystokinin was studied in nonpyramidal cells of the rat dorsal hippocampal formation. Neighbouring Vibratome sections were immunostained either for calbindin D28k and parvalbumin or for calbindin D28k and cholecystokinin. The cells, halved during sectioning, were identified in both sections immunostained for different antigens. The coexistence of calbindin D28k and parvalbumin in the same neuron was rare throughout the hippocampal formation with the exception of stratum oriens of the CA1 region, where 9.6% of the parvalbumin-immunoreactive cells also contained calbindin D28k. In stratum radiatum of the CA3 region, calbindin D28k and cholecystokinin coexisted in 12.5% and 21.2% of the calbindin D28k and cholecystokinin-immunoreactive cells, respectively. In other regions of the hippocampal formation, the two markers coexisted in less than 5% of the cells of either type. The present results demonstrate that calbindin D28k-, parvalbumin- and cholecystokinin-containing nonpyramidal cells represent largely nonoverlapping cell populations and may thus be involved in different inhibitory circuits.

Animals↗
PubMed1991

Different populations of parvalbumin- and calbindin-D28k-immunoreactive neurons contain GABA and accumulate 3H-D-aspartate in the dorsal horn of the rat spinal cord.

The colocalization of parvalbumin (PV), calbindin-D28k (CaBP), GABA immunoreactivities, and the ability to accumulate 3H-D-aspartate selectively were investigated in neurons of laminae I-IV of the dorsal horn of the rat spinal cord. Following injection of 3H-D-aspartate into the basal dorsal horn (laminae IV-VI), perikarya selectively accumulating 3H-D-aspartate were detected in araldite embedded semithin sections by autoradiography, and consecutive semithin sections were treated to reveal PV, CaBP and GABA by postembedding immunocytochemistry. Perikarya accumulating 3H-D-aspartate were found exclusively in laminae I-III, and no labelled somata were found in deeper layers or in the intermediolateral column although the labelled amino acid clearly spread to these regions. More than half of the labelled cells were localized in lamina II. In this layer, 16.4% of 3H-D-aspartate-labelled perikarya were also stained for CaBP. In contrast to CaBP, PV or GABA was never detected in neurons accumulating 3H-D-aspartate. A high proportion of PV-immunoreactive perikarya were also stained for GABA in laminae II and III (70.0% and 61.2% respectively). However, the majority of CaBP-immunoreactive perikarya were GABA-negative. GABA-immunoreactivity was found in less than 2% of the total population of cells stained for CaBP in laminae I-IV. A significant proportion of the GABA-negative but PV-immunoreactive neurons also showed CaBP-immunoreactivity in laminae II and IV. These results show that out of the two calcium-binding proteins, CaBP is a characteristic protein of a small subpopulation of neurons using excitatory amino acids and PV is a characteristic protein of a subpopulation of neurons utilizing GABA as a transmitter. However, both proteins are present in additional subgroups of neurons, and neuronal populations using inhibitory or excitatory amino acid transmitters are heterogeneous with regard to their content of calcium-binding proteins in the dorsal horn of the rat spinal cord.

Animals↗
PubMed1991

Calmodulin and calbindin localization in retina from six vertebrate species.

Calmodulin is abundant in the central nervous system, including the retina. However, the localization of calmodulin in the retina has not been described in detail. We therefore decided to investigate calmodulin localization in retinae from six vertebrate species, by using immunohistochemical labeling with four different rabbit polyclonal antibodies against calmodulin. The localization of calbindin-D28k, another calcium-binding protein already well described in retina, was compared. We found that calmodulin distribution is more highly conserved among species, contrasting with calbindin variability. The most striking result emerging is that calmodulin could not be detected in photoreceptors although other layers are intensely calmodulin-immunoreactive, casting doubt about a direct role of calmodulin in phototransduction. Horizontal cells are weakly calmodulin-immunoreactive, bipolar cells are calmodulin-immunoreactive except in turtle retina, numerous amacrine and ganglion cells are labeled in all species, and the fiber layer is always labeled. These data demonstrate that, while the calmodulin distribution in retina is similar among vertebrate species, selective differences in localization can be detected not only among the same cell types in different species but also among different cell types in the same species. The results showing differences in calmodulin immunoreactivity among cell types also provide further evidence that calmodulin expression in eukaryotes is not constitutive, in the sense that not every cell expresses similar levels of calmodulin.

Animals↗
PubMed1992

Heterogeneous development of calbindin-D28K expression in the striatal matrix.

In the present study, we attempted to trace the development of the striatal matrix by analyzing the ontogenetic expression of calbindin-D28K (calbindin), a calcium binding protein selectivity expressed in medium-sized neurons of the matrix compartment of the mature rat's caudoputamen. The localization of calbindin was documented in a series of developing rat brains, as was the compartmental location of these cells relative to tyrosine hydroxylase (TH)-immunostained dopamine islands, sites of future striosomes. Medium-sized striatal neurons appeared in the striatum at embryonic day (E) 20, and from their first appearance, the calbindin-positive neurons had highly heterogeneous distributions. They first formed a latticework of patches and bands in a ventral region of the caudoputamen. By postnatal day (P) 7, this early calbindin-positive lattice had evolved into a mosaic in which circumscript pockets of low calbindin-like immunoreactivity appeared in more extensive calbindin-rich surrounds. With further development, the mosaic gradually encroached on all but the dorsolateral caudoputamen, a district that is calbindin-poor at adulthood. A special lateral branch of the striatal calbindin system was also identified, distinct from the rest of the calbindin-positive mosaic in several developmental characteristics. In the parts of the caudoputamen where the developing calbindin system and dopamine island system were both present, the dopamine islands invariably lay in calbindin-poor zones. Most dopamine islands, however, only filled parts of the corresponding calbindin-poor zones. Moreover, there were some calbindin-poor zones for which TH-positive dopamine islands could not be detected. Thus during development, calbindin was expressed in the extrastriosomal matrix of the striatum, but the matrix could be divided into calbindin-rich and calbindin-poor zones. In the calbindin-rich regions, there were patches of especially intense calbindin expression and zones of weaker expression. These results suggest that there is neurochemical heterogeneity in the striatal matrix during the prolonged developmental period in which the early calbindin-positive lattice expands to form the calbindin-positive matrix of the mature striatum. Surprisingly, calbindin expression in the matrix, although eventually distributed in strictly complementary fashion to striosomes, does not originate as a system complementary to dopamine islands. The prolonged disparity between the borders of dopamine islands and calbindin-poor zones, and the different spatiotemporal schedules of development of the islands and the calbindin gaps suggest instead that the final match between the borders of striosomes and surrounding matrix results from dynamic processes occurring early in postnatal development. Candidate mechanisms for the gradual adjustment of these borders are proposed.

Aging↗
PubMed1990

Lurcher Purkinje cells express glutamic acid decarboxylase and calbindin mRNAs.

Purkinje neurons in immature Lurcher (Lc/+) mice are destined to die as a result of a defect intrinsic to the dying cells. We have used in situ hybridization to determine whether the Lc allele interferes with the normal program of gene expression in the doomed Purkinje cells. In P21 mice, degeneration of Purkinje cells is well underway, but the surviving Purkinje cells continue to express the mRNAs for both glutamate decarboxylase and calbindin D28K, two proteins whose expression is characteristic of normal Purkinje neurons. We conclude that the Lc allele probably does not interfere with the developmental program but acts to cause cell death in already differentiated Purkinje neurons.

Alleles↗
PubMed1992

Calbindin-D28K and ischemic damage of pyramidal cells in rat hippocampus.

An antibody against rat calbindin-D28K, a calcium-binding protein present at high concentration in certain neurons of the central and peripheral nervous systems, was used to determine the progression of the pathological events in the rat hippocampus following experimental cerebral ischemia. Calbindin-D28K immunoreactivity is present in dentate granule cells and in the CA1-CA2 pyramidal cells. CA1 subfield contains a higher proportion of calbindin-D28K-positive pyramidal cells than does the CA2 subfield and CA1 cells are more immunoreactive than the CA2 cells. The pyramidal cells of the CA1 and CA2 subfields are vulnerable to ischemia. The cells in the CA1 became necrotic within 3-4 days after ischemia while those of the CA2 became necrotic within 2 days. There was a concomitant decrease in calbindin-D28K immunoreactivity in the whole hippocampal regio superior after ischemia which peaked 3 days postischemia. The difference in CA2 and CA1 vulnerability seemed to be inversely correlated with the calbindin-D28K contents of the CA2 and CA1 pyramidal cells. The decrease in the calbindin-D28K contents of these neurons was accompanied by cell damage. We therefore suggest that calbindin-D28K is an important factor for the survival of pyramidal cells in the hippocampal formation after ischemia.

Animals↗
PubMed1991

Immunoreactive calcium-binding protein (calbindin-D28k) in interneurons and trigeminothalamic neurons of the rat nucleus caudalis localized with peroxidase and immunogold methods.

Calbindin-D28k is a highly abundant protein found in neurons in selected brain regions, including cells in sensory systems of the brainstem. Because of its capacity to bind cytosolic Ca++, calbindin-D28k is thought to contribute to the regulation of compartmental Ca++ concentrations in neurons. In this study of the rat spinal trigeminal nucleus, calbindin-D28k was localized with immunoperoxidase and immunogold methods. Results showed that immunoreactive calbindin-D28k neurons were widely distributed to all regions of the nucleus, but were particularly numerous in the substantia gelatinosa. Some trigemino-thalamic neurons that were identified by retrograde labeling of a conjugated wheat-germ agglutinin with horseradish peroxidase also contained calbindin-D28k immunoreactivity. Most of the calbindin-D28k labeling was found in cell bodies and dendrites. Axon terminals were rarely stained. More discrete labeling with a gold-conjugated second antibody showed that the predominant site of calbindin-D28k was the matrix of the cytoplasm. Gold label was also heavily associated with euchromatin within nuclei. These findings show that immunoreactive calbindin-D28k is localized to both interneurons and projecting neurons of the spinal trigeminal nucleus. Many of these cells are likely to receive glutamatergic afferent inputs, which may act in part by increasing Ca++ flux into the neurons. Calbindin-D28k has a high capacity for buffering Ca++ and under some conditions may protect neurons against glutamate-induced excitotoxicity. We speculate that calbindin-D28k may function to regulate calcium concentrations in spinal trigeminal neurons.

Animals↗