Parvalbumin-like Immunoreactivity Research Articles

Subdivisions of the auditory midbrain (n. mesencephalicus lateralis, pars dorsalis) in zebra finches using calcium-binding protein immunocytochemistry.

The midbrain nucleus mesencephalicus lateralis pars dorsalis (MLd) is thought to be the avian homologue of the central nucleus of the mammalian inferior colliculus. As such, it is a major relay in the ascending auditory pathway of all birds and in songbirds mediates the auditory feedback necessary for the learning and maintenance of song. To clarify the organization of MLd, we applied three calcium binding protein antibodies to tissue sections from the brains of adult male and female zebra finches. The staining patterns resulting from the application of parvalbumin, calbindin and calretinin antibodies differed from each other and in different parts of the nucleus. Parvalbumin-like immunoreactivity was distributed throughout the whole nucleus, as defined by the totality of the terminations of brainstem auditory afferents; in other words parvalbumin-like immunoreactivity defines the boundaries of MLd. Staining patterns of parvalbumin, calbindin and calretinin defined two regions of MLd: inner (MLd.I) and outer (MLd.O). MLd.O largely surrounds MLd.I and is distinct from the surrounding intercollicular nucleus. Unlike the case in some non-songbirds, however, the two MLd regions do not correspond to the terminal zones of the projections of the brainstem auditory nuclei angularis and laminaris, which have been found to overlap substantially throughout the nucleus in zebra finches.

Zinc-containing neurons are distinct from GABAergic neurons in the telencephalon of the rat.

We used a double-labeling protocol that combined the silver amplification of endogenous zinc with routine immunocytochemistry to determine if telencephalic neurons that exhibit GABA-, calbindin- or parvalbumin-like immunoreactivity give rise to zinc-containing boutons. We did not observe telencephalic neurons double-labeled for zinc and GABA or parvalbumin. Zinc and strong calbindin immunoreactivity were colocalized in hippocampal CA1 pyramidal cells and dentate granule cells. Other strongly calbindin-immunoreactive neurons of the telencephalon were never double-labeled. We conclude that GABAergic cells do not contain histochemically reactive zinc and, therefore, are unlikely to use this pool of zinc as a neuromodulator. This observation does not support an in vivo significance of the modulation of GABA receptors by zinc such as has been observed in vitro. In CA1 of the hippocampus, we observed the histochemical label for zinc in all visibly calbindin-immunoreactive pyramidal cells and vice versa. Thus, two markers define a subpopulation of hippocampal pyramidal cells.

Parvalbumin-like immunoreactivity of layer V pyramidal cells in the motor and somatosensory cortex of adult primates

Most previous immunocytochemical studies have indicated that the calcium-binding protein parvalbumin is present only in non-pyramidal neurons of the adult cerebral cortex. Using nickel and cobalt to enhance the diaminobenzidine reaction product, we observed large layer V pyramidal cells with parvalbumin-like immunoreactivity in the primary motor cortex (area 4) and somatosensory cortex of adult macaque monkeys and galagos, including giant Betz cells in area 4.

Differential distribution of calbindin-D28k and parvalbumin in somatic and visceral sensory neurons

The purpose of the present investigation was to determine whether calbindin-D28k and parvalbumin are distributed to different subpopulations of somatic and visceral sensory neurons. Immunofluorescent and retrograde techniques were combined to examine the distribution of calbindin- and parvalbumin-like immunoreactivity in the cell bodies of somatic and visceral primary afferent neurons in dorsal root ganglia L1-S1 of rats. Calbindin and parvalbumin were differentially distributed to essentially non-overlapping subpopulations of primary sensory neurons that could be distinguished by their segmental and size distributions, as well as by their innervation of somatic and visceral structures. Calbindin-like immunoreactivity was found in a population of smaller-sized cell bodies comprising approximately 14%of all dorsal root ganglion cells examined, with the proportions being greatest in L6 and S1. In contrast, parvalbumin was found in a population of larger-sized cells that made up about 11% of dorsal root ganglion cells and that were most concentrated in L4 and L5. Sensory neurons were further characterized by retrograde transport following the application of the neuroanatomical tracer FluoroGold to somatic (sural and gastrocnemius) and visceral (hypogastric and pelvic) nerves. Somatic tissues were innervated by a population of calbindin-containing as well as a separate population of parvalbumin-containing sensory neurons. In contrast, afferent neurons innervating visceral structures contained only a subpopulation of calbindin-containing neurons and very few parvalbumin-positive cells.

Parvalbumin expression reveals a vibrissa-related pattern in rabbit SI cortex

The expression of parvalbumin-like immunoreactivity (PV-LIR) was examined in the mystacial representation within the primary somatosensory cortex (SI) of postnatal day 21 and adult rabbits. PV-LIR was expressed in a prominent vibrissa-like array of patches in layer IV despite the fact that barrels were indistinct in the cytoarchitecture. Each patch consisted of dense terminal-like PV-LIR and a preferential concentration of intensely labeled stellate neurons. Layer V contained scattered small and large intensely labeled basket cells. Layer Vb had a distinct layer of lightly labeled large pyramidal cells that received labeled basket cell terminations. Upper layer VI also contained patches of terminal-like PV-LIR that were in register with the overlying vibrissae pattern. These patches also contained a preferential distribution of labeled non-pyramidal cells as well as modified pyramidal cells. These results suggest that PV-LIR in rabbits delineates cortical modules composed of thalamorcotical afferents and inhibitory local circuits in the absence of a distinct barrel cytoarchitecure. In contrast, prior studies of rat SI cortex have revealed a distinct barrel cytoarchitecture but a uniform distribution of PV-LIR. The differences in PV-LIR between rodents and lagomorphs within the vibrissae representation in SI may be related to species differences in thalamic and local cortical circuits devoted to the whisker sense.

Depletion and recovery of the calcium-binding proteins calbindin and parvalbumin in the pigeon optic tectum following retinal lesions

Retinal lesions in pigeons produced a marked depletion of somata and neuropil staining for both calbindin-D28k and parvalbumin immunoreactivities in the contralateral optic tectum. Calbindin-like immunoreactivity reappeared in some tectal layers by 6 weeks postlesion, whereas parvalbumin-like immunoreactivity recovered almost completely after 5 weeks. These data indicate that the retinal input may control the expression of calbindin and parvalbumin in the pigeon optic tectum.

Parvalbumin-like immunoreactivity in nerve fibres within human molar tooth pulps

The root pulp contained two types of parvalbumin-immunoreactive nerve fibres, smooth and varicose. The smooth were relatively thick (mostly 3–5 μm in diameter) and sometimes had large swellings, whereas the varicose consisted of oval varicosities of 1–3 μm in long diameter with very fine strands interconnecting them. Most of the parvalbumin-immunoreactive root fibres were smooth, and the varicose were rare. Upon entering the pulp chamber, both types of fibre splayed out and ran towards the roof of the chamber and the pulp horn. In the subodontoblastic layer of the roof and horn, parvalbuminimmunoreactive fibres showed relatively straight chains of granules; they sent their granular terminals to the odontoblastic layer. Some parvalbumin-immunoreactive granules were observed in the predentine and some even in the dentine. The diameter of axons in the root pulp and the spatial distribution of terminals strongly suggest that the parvalbumin-immunoreactive fibres are mostly myelinated and sensory.

Parvalbumin immunoreactivity: A reliable marker for the effects of monocular deprivation in the rat visual cortex

In mammals, monocular deprivation performed during the early stages of postnatal development (critical period) dramatically affects the functional organization of the visual cortex.1,6,22 Since the early work of Hubel and Wiesel, the effects of monocular deprivation are accounted for by the fibers driven by the two eyes competing for the control of cortical territories. In cat and monkey striking structural changes accompany the functional effects of monocular deprivation.7,14,15,21,23 Also, in the rat, monocular deprivation causes functional alteration at the level of visual cortex;5a,15a no structural correlates of these effects, however, have so far been described. Parvalbumin is a calcium binding protein that in the neocortex colocalizes with a subpopulation of GABAergic neurons.4,5 Here we report that in the rat monocular deprivation results in a dramatic reduction of parvalbumin-like immunoreactivity in the visual cortex contralateral to the deprived eye. This effect is due to competitive phenomena and not to visual deprivation itself, it is restricted to the binocular portion of the visual cortex and neither binocular deprivation, nor dark rearing can induce it. We conclude that parvalbumin-like immunoreactivity is a useful immunohistochemical marker for the effects of monocular deprivation in the rat visual cortex.

Spatial density and immunoreactivity of bipolar cells in the macaque monkey retina.

The anatomical substrates of spatial and color vision in the primate retina are investigated by measuring the immunoreactivity and spatial density of bipolar, amacrine and horizontal cells in the inner nuclear layer of the macaque monkey retina. Bipolar cells can be distinguished from amacrine and horizontal cells by their differential immunoreactivity to antisera against glutamate, glycine, GABA, parvalbumin, calbindin (CaBP D-28K), and the L7 protein from mouse cerebellum. The spatial density of bipolar cells is compared to the densities of photoreceptors and ganglion cells at different retinal eccentricities. In the centralmost 2 mm, cone bipolar cells outnumber ganglion cells by about 1.4:1. The density of cone bipolar cells is thus high enough to allow for input to different (parasol and midget) ganglion cell classes by different (diffuse and midget) bipolar cell classes. The density gradient of cone bipolar cells follows closely that of ganglion cells in central retina but falls less steeply in peripheral retina. This suggests that the convergence of cone signals to the receptive fields of ganglion cells in the peripheral retina occurs in the inner plexiform layer. The density of cone bipolar cells is 2.5-4 times that of cones at all eccentricities studied, implying that cone connectivity to bipolar cells remains constant throughout the retina. Different subgroups of bipolar cells are distinguished by their relative immunoreactivity to the different antisera. All rod and cone bipolar cells show moderate to strong glutamate-like immunoreactivity. The bipolar cells that show weak to moderate GABA-like immunoreactivity are also labeled with the antiserum to the L7 protein and are thus identified as rod bipolar cells. Nearly half of all cone bipolar cells showed glycine-like immunoreactivity. The results suggest that the inhibitory neurotransmitter candidates GABA and glycine are segregated respectively in rod and cone bipolar cell pathways. A diffuse, cone bipolar cell type can be identified by the anti-parvalbumin and the anti-calbindin antisera. All horizontal cells show parvalbumin-like immunoreactivity. Nearly all amacrine cells show GABA-like or glycine-like immunoreactivity; a variety of subpopulations also show immunoreactivity to one or more of the other markers used.

Distribution and ontogeny of parvalbumin immunoreactivity in the chicken retina

The distribution of parvalbumin-like immunoreactivity was studied in the embryonic and postnatal chicken retina. In post-hatched chickens, parvalbumin-like immunoreactivity was confined to amacrine cells. Three distinct subpopulations were identifiable based upon soma position and level of dendritic arborization in the inner plexiform layer. The primary dendrites from parvalbumin-immuno reactive amacrine cells descended vertically into the inner plexiform layer and eventually branched to give rise to a laminarly arrayed plexus in sublamina I, sublamina V and, to a lesser extent, at the boundary between sublaminae III and IV. Parvalbumin-like immunoreactive amacrine cells projecting to sublamina I of the inner plexiform layer were consistently monostratified. Some, but not all, contributed thick fibers to sublamina I that could be followed for long distances across the retina and were generally not radially organized. The parvalbumin-like immunoreactive cells that projected to sublamina V gave rise to a primary dendrite from which three to five fibers branched radially. Collateral branches of these same primary dendrites gave rise to the parvalbumin-like immunoreactive plexus at the interface between sublaminae III and IV. In prenatal chickens, parvalbumin-like immunoreactivity was not detected until embryonic day 14. At this time it appeared as a faint band at the inner nuclear layer-inner plexiform layer boundary in the central retina. By embryonic day 18 the intensity of immunoreactivity and the complexity of the arborizations of the parvalbumin-like immunoreactive dendrites approached that seen in the post-hatched chicken. In the chicken retina, parvalbumin-like immunoreactivity was displayed by morphologically distinct subpopulations of amacrine cells suggesting that these amacrine cells may subserve diverse functions. The long-distance projecting parvalbumin-like immunoreactive neurons, for instance, may contribute to the anatomical substrate for complex receptive fields. The appearance of parvalbumin relatively late in development may suggest that its expression requires the establishment of synaptic contacts and organized neuronal activity.

Distribution of parvalbumin immunoreactivity in the human brain

The cellular distribution of parvalbumin-like immunoreactivity (PA-LI) in the human brain was investigated by peroxidase-antiperoxidase methods using antiserum to rat skeletal muscle parvalbumin. PA-LI was present in non-pyramidal neurons of the cerebral cortices, stellate cells, basket cells and Purkinje cells in cerebellar cortices, and neurons of some nuclei in human brain stem; the distribution of PA-LI in human brain was very similar to that in rat brain. These results indicate that PA-LI is widely distributed in a specific subpopulation of neurons of the human brain.

Parvalbumin in rat superior colliculus

Parvalbumin-like immunoreactivity (PA-LI) has been studied in sections of the superior colliculus (SC) of the rat and its distribution compared to the patterns of acetylcholinesterase (AChE) and cytochrome oxidase (CO) staining. In the intermediate layers it was found that PA-LI is spatially associated with AChE only in the medial part of the SC, but assumes a complementary distribution further laterally. There was a positive correlation between PA-LI and CO. We conclude that the patterns of PA-LI and CO are not systematically related to collicular input known to be associated with the AChE-rich zones, but may reflect adherence to channel separation beyond the terminal fields of clustered afferents.

Parvalbumin immunoreactivity in the central auditory system of the gerbil: A developmental study

Changes in parvalbumin-like immunoreactivity were studied during ontogenetic development of the central auditory system of the Mongolian gerbil ( Meriones unguiculatus). The nucleus of the trapezoid body contained cells that could be stained on the day of birth while in the superior olivary complex, prominent staining of cell somata was only found at P15 (postnatal day 15). Neurons located in the ventral nucleus, in the dorsal nucleus of the lateral lemniscus and in the inferior colliculus developed parvalbumin immunoreactivity mostly between P11–P15 (ventral nucleus), P15–P19 (dorsal nucleus) and P15–P19 (inferior colliculus), respectively. The accumulation of PV correlates reasonably well with the functional maturation of the neurons in these areas.

Immunohistochemical localization of parvalbumin in rat and monkey autonomic ganglia.

The cellular distribution of parvalbumin-like immunoreactivity in autonomic ganglia such as superior cervical sympathetic ganglia, paravertebral sympathetic chain ganglia (T6), ciliary ganglia and enteric ganglia was investigated by immunohistochemical peroxidase-antiperoxidase methods using an antiserum against rat skeletal muscle parvalbumin. We detected parvalbumin-like immunoreactivity in almost all neurons of rat superior cervical sympathetic ganglia and other paravertebral sympathetic chain ganglia, where the antigen was located in the cytoplasm but the nuclei were not labelled. No neurons positive for parvalbumin-like immunoreactivity were observed in rat ciliary ganglia or enteric ganglia. In monkey, almost all neurons of the superior cervical sympathetic ganglia contained parvalbumin-like immunoreactivity, but none of the neurons of the ciliary ganglia were labelled with the antiserum to parvalbumin. These results suggest that parvalbumin-like immunoreactivity exists in a specific subpopulation of the neurons of the autonomic nervous system.

Immunochemical and immunohistochemical localization of parvalbumin in rat nervous tissues.

The contents of parvalbumin in various nervous tissues of the rat were measured by radioimmunoassay (RIA) and its cellular distribution was immunohistochemically examined by peroxidase-antiperoxidase methods. The antibody, raised in rabbits using rat skeletal muscle parvalbumin, did not cross-react with other Ca2+-binding proteins such as calmodulin or S-100 proteins. The RIA demonstrated the wide distribution of the antigen, with very high levels in the cerebellum (3,217 +/- 519 ng/mg protein). The immunohistochemical description by Celio and Heizmann [Nature 293, 300-302 (1981)] was confirmed concerning the existence of the antigen in Purkinje cells of the cerebellum; nonpyramidal neurons of the cerebral cortex; and medium-sized cells of the olfactory bulb, hippocampus, and reticular nucleus of the thalamus. In addition to these neurons, we found the parvalbumin-like immunoreactivity in the large neurons of the superior vestibular nucleus and the neurons of the medial superior olive nucleus. In the gamma-aminobutyric acid (GABA)-containing nuclei such as substantia nigra, caudatoputamen, and globus pallidus, parvalbumin-positive cells and fibers were rare. In the medial lemniscus of the midbrain which contains no GABA, parvalbumin-immunoreactive fibers were prominent. The possibility was discussed that parvalbumin exists in a specific population of neurons that differ from those containing GABA.

Parvalbumin in rat cerebrum, cerebellum and retina during postnatal development

Radioimmunoassay and immunohistochemical studies were performed on the occurrence and distribution of parvalbumin-like immunoreactivity (PA-LI) in developing rat cerebrum, cerebellum and retina. No PA-LI was detected in the nervous tissues of the newborn animals. In the cerebrum, the PA-LI appeared in non-pyramidal neurons at the 2nd postnatal week and increased linearly until the 8th week. In the cerebellum, a rapid increase in the PA-LI took place at the 2nd week, with an enrichment of the antigen to Purkinje neurons. In the retina, amacrine cells contained PA-LI, the levels of which increased from the 2nd to 4th week. Regulation of intracellular Ca 2+ concentration may be one of the important factors for the maturation of the central nervous system.