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H J Karten

Publications and source records attributed to H J Karten.

At least 91 records · Page 5Linked to original sources
PubMed1983

Comparison of fixation and penetration enhancement techniques for use in ultrastructural immunocytochemistry.

Electron microscopic immunohistochemistry, although generally providing good localization, has often failed to produce satisfying ultrastructural preservation. Techniques that result in well-preserved tissue ultrastructure often hinder penetration of immunological reagents or render antigens non-immunoreactive. These are particularly serious limitations in studies of central nervous system and retina. We have evaluated several fixatives, including picric acid, high pH paraformaldehyde, and glutaraldehyde with subsequent sodium borohydride treatment, and penetration enhancement techniques, including buffered-ethanolic treatment and freeze--thaw, for their applicability in the retina. Our best fixation was achieved with 1 hr in 4% paraformaldehyde and 0.2% glutaraldehyde (pH 7.4) followed by overnight fixation in 4% paraformaldehyde (pH 10.4). Treatment with sodium borohydride after glutaraldehyde fixation restores much of the immunoreactivity that would otherwise be undetectable. The penetration of immunological reagents can be greatly increased by using either a buffered-ethanolic series or by freezing the tissue after careful cryoprotection. Using these methods we have been able to achieve specific immunological staining throughout the full thickness of retinal slices, up to 500 microns across, while preserving good ultrastructure. The methods should prove useful in the immunocytochemical localization of many different antigens in a variety of tissues.

Animals↗
PubMed1982

Laminar organization of peptide-like immunoreactivity in the anuran optic tectum.

Peptide, 5-hydroxytryptamine (5-HT)-, tyrosine hydroxylase (TOH)-, and glial fibrillary acidic protein (GFAP)-like immunoreactivity was studied in the optic tectum of Rana pipiens. Peroxidase-antiperoxidase and indirect immunofluorescence single- and double-labeling methods were used to compare differential laminar distribution of each of these substances. Substance P (SP), leucine-enkephalin (LENK), cholecystokinin octapeptide (CCK8), bombesin (BOM), avian pancreatic polypeptide (APP), and possibly neurotensin display unique individual patterns of laminar distribution of processes and cell bodies throughout the tectum. A correlative analysis of the topographical distribution of SP, LENK, BOM, and APP on the basis of double-labeled sections shows a precise laminar segregation of these substances. Vasoactive intestinal peptide-, beta-endorphin-, and ranatensinlike immunoreactivity is consistently absent from our material. 5HT- and TOH-like immunoreactivity discloses a reticular array of fibers without clear evidence of laminar organization. This peptide-like laminar organization is particularly elaborate throughout the superficial neuropil of the optic tectum, the major retinorecipient zone. The pattern of lamination demonstrated in the present study differs in several important features from that previously described on the basis of several histological methods. The cells of origin of processes (axons and/or dendrites) in the superficial tectal neuropil may be either intrinsic or extrinsic to the tectum. Special reference is made to conflicting evidence regarding the possibility of a retinal contribution to peptide-like tectal lamination.

Animals↗
PubMed1982

Basal ganglia pathways to the tectum: the afferent and efferent connections of the lateral spiriform nucleus of pigeon.

Previous studies have demonstrated that the lateral spiriform nucleus (SpL) of the avian pretectum receives a major input from the ipsilateral basal ganglia (Karten and Dubbeldam, '73) and projects to the ipsilateral optic tectum (Brecha et al., '76). The present study has further detailed the anatomical organization of the afferent and efferent connections of SpL, with particular reference to (1) the sources of afferent inputs to SpL, (2) the projection targets of SpL, and (3) the laminar termination pattern of the SpL projection to the tectum. The SpL was found to receive clear-cut major inputs from only three nuclei: (1) the ipsilateral paleostriatum primitivum (PP) of the basal ganglia (the avian homologue of the mammalian globus pallidus), (2) the ipsilateral anterior nucleus of the ansa lenticularis (ALa) of the diencephalon, and (3) the ipsilateral nucleus tegmentipedunculopontinus (TPc) of the mesencephalon. Both TPc and ALa have previously been noted themselves to receive major inputs from the ipsilateral PP (Karten and Dubbeldam, '73). Two other cell groups may give rise to a slight projection to the ipsilateral SpL: (1) the posterior nucleus of the ansa lenticularis (ALp) of the diencephalon and (2) the nucleus semilunaris (SLu) of the isthmic brainstem. The ALp also receives a major input from PP (Karten and Dubbeldam, '73). Two other cell groups may give rise to a slight projection to the ipsilateral SpL: (1) the posterior nucleus of the ansa lenticularis (ALp) of the diencephalon and (2) the nucleus semilunaris (SLu) of the isthmic brainstem. The ALp also receives a major input from PP (Karten and Dubbeldam, '73), while SLu receives a major tectal projection (Hunt and Kunzle, '76a). The ipsilateral tectum was found to be the only projection target of SpL. The present data suggest that the SpL projection to the tectum is restricted to layers 8-13, with layers 11-13 receiving the heaviest projection from SpL. Among layers 8-10, layer 9 receives the lightest projection from SpL. The present results indicate that SpL receives only a limited number of inputs, which in all likelihood relay largely basal ganglia input to SpL. Since SpL projects only to the tectum, the sole function of SpL apparently is the transmission of ipsilateral basal ganglia influences to the avian optic tectum. Tectal layers 8-15 have been previously found to represent the layers of origin of the descending pathways of the avian tectum to hindbrain motor and "premotor" cell groups (Reiner and Karten, '82). In view of the purported involvement of the basal ganglia in motor functions, the basal ganglia pathway to the ipsilateral tectum via SpL may represent a major route by which the avian basal ganglia exert influences over motor functions.

Afferent Pathways↗
PubMed1982

Enkephalin-mediated basal ganglia influences over the optic tectum: immunohistochemistry of the tectum and the lateral spiriform nucleus in pigeon.

By using immunohistochemical techniques with antisera directed against either leucine-enkephalin or methionine-enkephalin (generously supplied by K.-J. Chang), four distinct bands of fibers with enkephalinlike immunoreactivity were demonstrated in the pigeon tectum: (1) a thin band of thick fibers and tightly clustered bulbous swellings in layer 3, (2) a broader band of fibers with less tightly clustered bulbous swellings in layer 5, (3) a broad band of numerous obliquely and radially oriented fibers that spanned layers 8-13, and (4) a band of sinuous fibers in layer 15. In addition, numerous enkephalinergic cell bodies with radially ascending processes were seen in layers 8-10. Since the neurons of the avian lateral spiriform nucleus (SpL) of the pretectum are known to contain enkephalin (Davis et al., '80; De Lanerolle et al., '81) and project to the tectum (Brecha et al., '76; Reiner et al., '82), unilateral electrolytic lesions were made of SpL. In birds with unilateral lesions of SpL, layers 8-13 of the ipsilateral tectum were nearly devoid of enkephalinergic fibers, but no alterations were seen in layers 3, 5, and 15. Since no other neurons in the vicinity of SpL are enkephalinergic and project to the tectum, the loss of enkephalin-immunoreactive fibers in the ipsilateral tectal layers 8-13 is attributable to the destruction of SpL. Although the source of the enkephalinergic fibers in tectal layers 3, 5, and 15 is unclear, part of the enkephalin pattern in layers 3 and 5 may derive from the ascending processes of the enkephalinergic neurons of layer 8-10. The present results indicate that SpL has an enkephalinergic projection to layers 8-13 of the ipsilateral tectum. The avian SpL receives its major input from the ascending processes of the enkephalinergic neurons of layers 8-10, nuclei that themselves receive major basal ganglia inputs (Reiner et al., '82) and projects to the tectal layers 8-13 (Reiner et al., '82), the layers of origin of the major tectal efferent projections (Reiner and Karten, '82). The enkephalinergic fibers in layers 8-13 may, thus, have some influence upon the motor output functions of the avian tectum.

Animals↗
PubMed1982

Distribution of enkephalin-like immunoreactivity in the rat main olfactory bulb.

Enkephalin-like immunoreactivity was localized within the main olfactory bulb of the rat using immunohistochemical techniques. These studies utilized well characterized antisera directed to either leu5- or met5-enkephalin. Specificity was established by absorption of the antisera with either 10 microM synthetic leu5- or met5-enkephalin. Specific enkephalin-like immunoreactivity was observed within several different cell populations including (1) periglomerular cells, (2) granule cells and their processes within the external plexiform layer and (3) occasional short-axon (horizontal) cells within the granule and external plexiform layers. The granule cell layer contained the greatest number of immunoreactive cells. Only a limited number of immunoreactive cells were found in both the periglomerular and granule cell layers, suggesting the enkephalin-containing neurons represent a sub-population within each layer. The absence of immunoreactive processes in the periventribular white matter, as well as the morphologies of immunoreactive bulbar neurons, indicates that enkephalin is found exclusively within intrinsic olfactory bulb neurons.

Animals↗
PubMed1982

Substance P-containing neurons of the avian suprachiasmatic nucleus project directly to the nucleus of Edinger-Westphal.

Retrograde and anterograde pathway tracing techniques were used in the pigeon to study afferent visual input from the suprachiasmatic nucleus (SCN) of the hypothalamus to the nucleus of Edinger-Westphal (EW), the parasympathetic visceral efferent component of the oculomotor complex. Horseradish peroxidase injected into the EW retrogradely labeled numerous neurons in the contralateral SCN, a retinorecipient hypothalamic nucleus, as well as a few neurons in the ipsilateral SCN. Autoradiographic orthograde pathway tracing experiments confirmed that the SCN projects heavily upon the medial subdivision of the contralateral EW and lightly upon the medial subdivision of the ipsilateral EW. Some neurons of the SCN contain substance P and a substance P-positive plexus of fibers was seen in precisely that medial portion of the EW to which the SCN was found to project in the autoradiographic experiments. This substance P-positive fiber plexus in the medial EW was eliminated by bilateral electrolytic lesions of the SCN. These results show that the avian suprachiasmatic nucleus has a heavy contralateral and a much lighter ipsilateral projection to the medial subdivision of the EW and that this projection may be largely substance P positive. Previous studies have suggested that neurons of the medial EW specifically project to the neurons of the ciliary ganglion that control the choriocapillary blood flow of the eye. Since the SCN has been implicated in the control of circadian rhythms in vertebrates, the projection of the SCN to the EW may represent a pathway by which a circadian rhythmicity is imposed on choriocapillary blood flow. Alternatively or in addition, the SCN-EW pathway described in this paper may provide the central neural substrate for a homeostatic regulatory mechanism by which choriocapillary blood flow is controlled by the intensity of retinal illumination.

Animals↗
PubMed1982

Localization of substance P-like immunoreactivity within the monkey retina.

Substance P (SP)--like immunoreactivity has been localized to distinct retinal cell populations in the primate Macaca nemestrina by means of immunohistochemical techniques with a well-characterized monoclonal antiserum directed to SP. The specificity of the immunoreactive staining was established by absorption of the antiserum with 10 micro M synthetic SP. Specific SP-like immunoreactivity was observed within varicose processes located in the outer plexiform layer, inner nuclear layer (INL), and in three bands within the inner plexiform layer (IPL). SP-immunoreactive somata were located in the proximal INL, IPL, and ganglion cell layer. These studies have thus identified SP-containing amacrine cells, interstitial amacrine cells, and displayed amacrine cells. In addition, these studies suggest the existence of SP-containing interplexiform cells and perhaps ganglion cells.

Animals↗
PubMed1982

Localization of substance P-like and enkephalin-like immunoreactivity within preganglionic terminals of the avian ciliary ganglion: light and electron microscopy.

The avian ciliary ganglion receives its only recognized input from the nucleus of Edinger-Westphal. This is known to be a cholinergic input. In the present study, using fluorescein isothiocyanate and peroxidase-antiperoxidase immunohistochemical methods, substance P-like and enkephalin-like immunoreactivity has been found within preganglionic terminals of the avian ciliary ganglion. The ciliary ganglion is known to consist of two distinct cell populations: small choroid cells that project to the smooth muscle coat of the choroid and large ciliary neurons that send axons to both the iris and the ciliary body. Preganglionic terminals on choroid cells consist of small boutonal endings, whereas ciliary neurons receive a calyx-like cap ending around the hilus of the cell. Substance P-like and enkephalin-like immunoreactivity was localized to preganglionic axons and to both boutonal and calyx-like terminations upon cells of the ciliary ganglion. Electron microscopic studies of both substance P-like and enkephalin-like immunoreactive terminals revealed small clear core vesicles (approximately 58 nm in diameter) and two sizes of dense core vesicles (approximately 85 and approximately 119 nm in diameter). Immunoreactive staining was observed only in the smaller dense core vesicles. The unlabeled clear core vesicles were clustered at synaptic release sites, while the immunoreactive and larger unlabeled dense core vesicles usually were not near these synaptic specializations. These observations strongly imply that neuropeptides co-occur with acetylcholine in preganglionic axons of the ciliary ganglion.

Animals↗
PubMed1981

Localization of enkephalin-like immunoreactivity to identified axonal and neuronal populations of the rat hippocampus.

The distribution of enkephalin-like immunoreactivity in the hippocampal formation of the rat was analyzed. Two specific projection systems are described. The first emerges from the hilus of the dentate gyrus and appears to terminate with notably large boutons on the proximal apical and, to a lesser extent, basal dendrites of hippocampal regio inferior pyramidal cells. This projection corresponds in source, position, and character to the hippocampal mossy fiber system. The second axonal population enters the temporal hippocampal formation from the medial wall of the subicular complex and follows the hippocampal fissure to occupy stratum lacunosum-moleculare of the hippocampus proper and the distal third of the dentate gyrus molecular layer; this pattern corresponds to the distribution of afferent input from the lateral entorhinal cortex and/or perirhinal area. Lesions of the hilus or retrohippocampal area caused a selective depletion of immunoreactivity in the mossy fiber fields and molecular layers of the dentate gyrus, respectively. Enkephalin-like immunoreactivity was found within the somata of three types of hippocampal neurons: 1) granule cells of the dentate gyrus, 2) occasional pyramidal shaped cells of field CA1 stratum pyramidale, and 3) varied scattered interneurons. Of this last group, two types of interneurons were consistently seen. The first occupy the border between stratum radiatum and stratum lacunosum-moleculare and extend processes at right angles to the long axis of the pyramidal cell dentrites, whereas the second lie within stratum radiatum of field CA1 and extend processes in alignment with the long axis of the pyramidal cell dendrites. Cells containing enkephalin-like immunoreactivity were also observed in the subiculum and retrohippocampal region, most notably including layers II and III of the lateral entorhinal cortex-perirhinal area--the probable source of extrinsic immunoreactive input to the hippocampal formation. Intraventricular colchicine treatment intensified the immunoreactive staining of some hippocampal neurons but did not reveal any cell types not seen to be labeled in untreated rats.

Animals↗
PubMed1981

Displaced ganglion cells and the accessory optic system of pigeon.

The central projection and retinal distribution of displace ganglion cells (DGC's) are described for the pigeon. Discrete, localized injections of horseradish peroxidase (HRP) into the nucleus of the basal optic root (nBOR) complex labeled as many as 4,800 DGC's in the contralateral retina. The greatest densities of DGC's were observed in the more peripheral regions of the middle and inferior temporal regions of the retina, with lowest densities occurring in the inferior nasal, red field, and foveal areas. Large HRP injections of the tectal lobes, which did not include the pretectal, accessory optic (nBOR), hypothalamic, or thalamic visual nuclei, labeled only ganglion cells within the ganglion cells layer. An HRP injection centered within the nucleus lentiformis mesencephali, also including portions of the optic tectum and optic tract, labeled only ganglion cells within the ganglion cell layer of the contralateral retina. DGC's thus appear to be the primary, if not exclusive, source of retinal afferents to the nBOR complex in pigeon. The observed retinal distribution of DGC's indicates that the areas of retina with the greatest density of cells in the receptor layer, inner nuclear layer, and ganglion cell layer are relatively devoid of DGC's. Since the nBOR complex projects directly upon the vestibulocerebellum and oculomotor nuclei, DGC's would thus appear to be involved in neural circuits that mediate oculomotor reflexes and visuomotor behavior.

Animals↗
PubMed1981

Terminal distribution of retinal fibers in the tegu lizard (Tupinambis nigropunctatus).

The retinal projections in the tegu lizard were traced using degeneration-silver methods. Bilateral projections were found to the dorsolateral geniculate and the posterodorsal nuclei. Unilateral, crossed projections were traced to the suprachiasmatic nucleus, the ventrolateral geniculate nucleus, the mesencephalic lentiform nucleus, nucleus geniculatus praetectalis, the ectomammillary nucleus, and the optic tectum. Some of these connections are distinctly different from those reported in other reptiles and suggest that important interspecific variations occur among reptiles.

Animals↗