Immunocytochemical localization of amino acid neurotransmitter candidates in the ventral horn of the cat spinal cord: a light microscopic study

The distribution of immunoreactivities to six amino acids, possibly related to synaptic function, was investigated in the motor nucleus of the cat L7 spinal cord (laminae VII and IX) using a postembedding peroxidase-antiperoxidase technique. Consecutive 0.5 m transverse sections of plastic-embedded tissue were incubated with antisera raised against protein-glutaraldehyde conjugates of -aminobutyric acid (GABA), glycine, aspartate, glutamate, homocysteate, and taurine. This method allowed localization of the different immunoreactivities in individual cell profiles. The results showed that all these amino acids, except homocysteate, could be clearly detected in either neuronal or glial elements in the ventral horn. In cell bodies of neurons in lamina VII, immunoreactivity was observed for aspartate, glutamate, GABA, and glycine. Adjacent section analysis revealed that combinations of immunoreactivity for glycine/glutamate/aspartate, GABA/glycine/glutamate/aspartate and glutamate/aspartate, respectively, may occur in one and the same cell. In the motor nuclei (lamina IX), immunoreactivity to amino acids was observed in two types of neuron. Large cells, probably representing -motoneurons, were harboring immunoreactivity to both glutamate and aspartate, while a few small neurons in this area displayed a colocalization of glycine, glutamate, and aspartate. Dendrites and axons in the motor nuclei cocontained glycine/glutamate/aspartate, GABA/glycine/glutamate/aspartate, and glutamate/aspartate immunoreactivities. In both laminae VII and IX, taurine-like immunoreactivity was absent in neuronal cell bodies, but highly concentrated in perivascular cells and small cells with a morphology resembling that of glial cells. A punctate immunolabeling, in all probability representing labeling of nerve terminals, could be demonstrated in the ventral horn for GABA, glycine, and glutamate, but not with certainty for aspartate or taurine. A quantitative estimate of the covering of cell bodies of -motoneuron size by immunoreactive puncta revealed that glycine immunoreactive terminal-like structures were most abundant (covering 26–42% of the somatic membrane), while glutamate immunoreactive terminals were seen least frequently (5–9% covering). GABA-immunoreactive terminals covered from 10 to 24% of the soma surface. A colocalization of GABA and glycine immunoreactivities in putative nerve terminals could be shown both in the neuropil and in close relation to cell bodies of motoneurons. These results suggest that among the studied amino acids probably only three, namely GABA, glycine, and glutamate, can be considered to be neurotransmitter candidates in the ventral horn of the cat spinal cord.     

The structure of rabbit retinal Müller (glial) cells is adapted to the surrounding retinal layers

Summary Radial glial (Müller) cells of the rabbit retina were studied by various techniques including Golgi impregnation, scanning electron microscopy, horseradish peroxidase application, and staining of enzymatically isolated cells. This combination of methods produced detailed information on the specialized morphology of the Müller cells within the different topographical regions of the retina, and of the Müller cell processes within the various retinal layers. As a general rule, the retinal periphery contains short thick Müller cells with big endfeet, whereas the thick central retina is occupied by long slender cells with small endfeet. Independent of their location within the retina, Müller cell processes were found to be adapted to the structure of the surrounding retinal layers. Within the outer and inner nuclear layers, Müller cell processes (and somata) extend thin cytoplasmic bubbles ensheathing the neuronal somata, as do the velate astrocytes in the brain. In the plexiform layers, Müller cells extend many fine side branches between the neuropil, comparable to the protoplasmic astrocytes of the brain. In the thick myelinated nerve fibre layer of the central retina the Müller cell processes are rather smooth, similar to those of fibrous astrocytes. It is concluded that the neuronal microenvironment determines the morphology of a given glial process, or even of a part of a glial process running through a specialized neuronal compartment.     

A molecular phenotype atlas of the zebrafish retina

The rasborine cyprinid Danio rerio (the zebrafish) has become a popular model of retinal function and development. Its value depends, in part, on validation of homologies with retinal cell populations of cyprinine cyprinids. This atlas provides raw and interpreted molecular phenotype data derived from computationally classified sets of small molecule signals from different cell types in the zebrafish retina: L-alanine, L-aspartate, L-glutamine, L-glutamate, glutathione, glycine, taurine and -aminobutyrate. This basis set yields an 8-dimensional signature for every retinal cell and formally establishes molecular signature homologies with retinal neurons, glia, epithelia and endothelia of other cyprinids. Zebrafish photoreceptor classes have been characterized previously: we now show their metabolic profiles to be identical to those of the corresponding photoreceptors in goldfish. The inner nuclear layer is partitioned into precise horizontal, bipolar and amacrine cell layers. The horizontal cell layer contains at least three and perhaps all four known classes of cyprinine horizontal cells. Homologues of cyprinid glutamatergic ON-center and OFF-center mixed rod-cone bipolar cells are present and it appears likely that all five classes are present in zebrafish. The cone bipolar cells defy simple analysis but comprise the largest fraction of bipolar cells, as in all cyprinids. Signature analysis reveals six molecular phenotypes in the bipolar cell cohort: most are superclasses. The amacrine cell layer is composed of 64% GABA+ and 35% glycine+ amacrine cells, with the remainder being sparse dopaminergic interplexiform cells and other rare unidentified neurons. These different amacrine cell types are completely distinct in the dark adapted retina, but light adapted retinas display weak leakage of GABA signals into many glycinergic amacrine cells, suggesting widespread heterocellular coupling. The composition of the zebrafish ganglion cell layer is metabolically indistinguishable from that in other cyprinids, and the signatures of glial and non-neuronal cells display strong homologies with those in mammals. As in most vertebrates, zebrafish Müller cells possess a high glutamine, low glutamate signature and contain the dominant pool of glutathione in the neural retina. The retinal pigmented epithelium shows a general mammalian signature but also has exceptional glutathione content (5–10 mM), perhaps required by the unusually high oxygen tensions of teleost retinas. The optic nerve and the marginal zone of the retina reveal characteristic metabolic specializations. The marginal zone is strongly laminated and its nascent neurons display their characteristic signatures before taking their place in the retina proper.     

Alterations of Müller (glial) cells in dystrophic retinae of RCS rats

Summary We have carried out a light microscopical study of Müller cells in the retinae of rats with inherited retinal dystrophy (Royal College of Surgeons rats). Isolated retinae of both control and Royal College of Surgeons rats were exposed to a Procion Yellow solution which is taken up selectively into Müller cells. The shape of the cells was then studied by confocal microscopy. Enzymatically isolated Müller cells were studied immunocytochemically with antibodies against glial fibrillary acidic protein, cathepsin D, -amyloid precursor protein, bcl-2 protooncogene product, and glutamine synthetase. Müller cells from RCS retinae were shorter than those from control retinae, and showed a coarse hypertrophy of their distal (sclerad) processes. In Müller cells isolated from the retinae of Royal College of Surgeon's rats, the expression of glial fibrilliary acidic protein, cathepsin D, -amyloid precursor protein and bcl-2 protooncogene product was increased, and the expression of glutamine synthetase was reduced. Obviously, loss of neighbouring neurons leads to major alterations of both the shape and metabolism of Müller cells. The expression of enzymes that serve functional glio-neuronal interactions, such as glutamine synthetase, seems to be down-regulated, whereas proteins involved in cell reconstruction (cathepsin D), cell repair (possibly -amyloid precursor protein), and protection against apoptotic cell death (bcl-2 protooncogene product), are up-regulated, together with the pathological marker glial fibrilliary acidic protein.     

4B2: A monoclonal antibody to ganglion and bipolar cells in the retina of the cat, generated by intrasplenic immunization

Summary Using tissue from the inner layers of the retina as the immunogen, we have prepared a monoclonal antibody which is selective for two classes of neuron in the cat retina. The antibody, termed 4B2, was generated by intrasplenic injection, demonstrating that neuron-specific antibodies can be elicited by this technique, which requires only micrograms of immunogen. The 4B2 binds to the somas, dendrites and axons of ganglion cells. Double labelling with 4B2 and with a retrograde tracer injected into the retino-recipient nuclei of the brain demonstrates that, of the cell classes in the ganglion cell layer, 4B2 labels only ganglion cells, and that, amongst ganglion cells, 4B2 is strongly selective for large (-) and medium-sized (- and perhaps -) cells. Double labelling with 4B2 and with markers for amacrine cells confirms tht 4B2 does not label amacrine cells. Double labelling with 4B2 and with anti-GFAP confirms that 4B2 does not label the macroglia of the retina. The 4B2 also labels bipolar cells, showing their somas, dendrites and axons. The axons of the labelled cells terminate in large boutons, in the innermost part of the inner plexiform layer and in the ganglion cell layer. This level of termination suggests that 4B2 labels rod bipolars, and perhaps a subgroup of cone bipolars. Double labelling with 4B2 and with markers for amacrine, horizontal and Müller cells indicates that other cell classes with somas in the inner nuclear layer remain unlabelled. In addition, we have examined the ontogeny of 4B2 labelling in the cat retina. The developmental sequence of labelling with 4B2 follows the sequence in which the cells are born, first ganglion and then bipolar cells.     

Effects of kainic acid and piperidine dicarboxylic acid on displaced bipolar cells in the turtle retina

Summary An immunoreaction against glutamate was used to visualize photoreceptors, bipolar, and ganglion cells in the turtle retina. Incubation of the retina prior to fixation in kainic acid (9 m) led to selective loss of glutamate-like immunoreactivity in OFF-centre bipolar cells, as judged by the loss of staining in the distal half of the inner plexiform layer. In addition, displaced bipolar cells and ganglion cells lost their immunoreactivity. Incubation of the retina in 2,3-cis piperidine dicarboxylate (1mm) did not result in noticeable glutamate depletion in any cell but enhanced labelling in displaced bipolar cells. These findings suggest that all displaced bipolar cells in the turtle retina are depolarized by kainic acid and hyperpolarized by 2,3-cis piperidine dicarboxylate.     

Morphometric parameters of Müller (glial) cells dependent on their topographic localization in the nonmyelinated part of the rabbit retina. A consideration of functional aspects of radial glia

Summary Morphometric parameters of Müller cells were evaluated by light microscopy both in whole retinae and in enzymatically isolated cells from adult pigmented rabbits. In spite of the marked decrease in cell densities from visual streak to far periphery, a constant glia-neuron ratio of about 115 was found in all regions. The volume of individual Müller cells was found to increase strongly when the cells become shorter, i.e. when the retinal centre was compared to the retinal periphery. The contribution of Müller cell volume to the total retinal volume, however, was shown to be constant at about 6%. Long Müller cells have a thin vitreal process and a small vitreal endfoot surface. The consequences of this rule for the proposed function of Müller cells in retinal K⁺ clearance are discussed with respect to general features of radial glia. It is suggested that foetal radial glial cells too long to perform sufficient K⁺ clearance are destined to be transformed into adult multipolar glia by mitotic cell division.     

Die Aussagefähigkeit des LPI nach E. A. Müller bei der Beurteilung der körperlichen Leistungsfähigkeit von Trainierten und Untrainierten

Zusammenfassung Um zu prüfen, ob sich der LPI-Wert von Sportlern wesentlich von den aus der Literatur bekannten Werten für Untrainierte unterscheidet, wurde der LPI an zwei Kollektiven von Spitzen-Radsportlern und Sportstudenten bestimmt. Die Ergebnisse zeigen, daß der Mittelwert von 11 Radsportlern (2,84 ± 0,36) und von 24 Sportstudenten (2,66 ± 0,65) im Bereich des von E. A. Müller mit 2,8 ± 0,6 angegebenen Mittelwerts für normale Männer liegt. Der LPI scheint weitgehend trainingsresistent zu sein, daher kann man die körperliche Dauerleistungsfähigkeit von Versuchspersonen unterschiedlichen Trainingszustands nicht mit dem LPI erfassen. Da andererseits ein Zusammenhang zwischen einem kleinen LPI-Wert und einer guten körperlichen Leistungsfähigkeit anzunehmen ist, könnte der LPI ein Maß für die Eignung (Talent) zu körperlicher Ausdauerleistung sein.     

Localization of GABA and glycine in goldfish retina by electron microscopic postembedding immunocytochemistry: improved visualization of synaptic structures with LR White resin

Summary A post-embedding, electron microscopic immunocytochemistry technique, modified from existing protocols, was used to examine the labelling patterns of GABA immunoreactivity and glycine immunoreactivity in goldfish retina. Retinae were fixed in mixed aldehyde solution, dehydrated in ethanol, staineden bloc with uranyl acetate and phosphotungstic acid and embedded in LR White resin. Substances were localized in thin sections by floating grids first on a drop of primary antiserum and then on a colloidal gold-IgG conjugate. Finally, grids were exposed to osmium vapour. The localization of GABA immunoreactivity matched that of [³H]-GABA uptake or glutamate decarboxylase immunoreactivity as described previously. In the outer retina, GABA immunoreactivity was found in the cell bodies and axon terminals of H1 horizontal cells and their dendrites opposite cone photoreceptor terminals. Selected amacrine cell bodies were labelled, as were many processes, both synaptic and non-synaptic, throughout the inner plexiform layer, including most amacrine cell processes contacting the synaptic terminals of type Mb bipolar cells. Numerous amacrine cells, their processes in the inner and outer plexiform layers, and photoreceptor terminals contained glycine immunoreactivity in a distribution similar to that shown by [³H]-glycine uptake. Despite the absence of osmium in the primary or secondary fixative, our protocol results in excellent visibility of synaptic structures and detectability of the colloidal gold immunolabel. Also, it does not cause extraction of the HRP/DAB reaction product and is therefore suitable for double-label analysis of neurons labelled with horseradish peroxidase.     

GABAergic innervation of rat abducens motoneurons retrogradely labelled with HRP: quantitative ultrastructural analysis of cell bodies and proximal dendrites

Summary In this quantitative electron microscopic study we investigated the distribution of GABA axon terminals on rat abducens motoneurons by combining retrograde labelling of motoneurons with post-embedding immunodetection of GABA. We analysed the synapses on 13 cell bodies and 60 proximal dendritic profiles distributed along the entire rostro-caudal extent of the nucleus. For each of these two compartments, we analysed 1754 and 1176 axon terminals in contact with 6042 and 3299 m of postsynaptic membrane. The axon terminals were classified as Sv-type (containing spherical vesicles) or Pv-type (containing pleomorphic vesicles). The GABAergic terminals contained pleomorphic vesicles and established mainly symmetrical synaptic contacts. Their apposition lengths were greater than those of unlabelled terminals. On cell bodies, the percentage of GABAergic synaptic covering varied from 2.5% to 14.1% and the synaptic frequency of GABAergic axon terminals varied from 0.6% to 8.9%. These two parameters were significantly correlated with the diameter of the motoneurons. The percentage of synaptic covering and synaptic frequency were smaller on dendrites of small motoneurons than on those of large ones. The proximal dendrites of small motoneurons had a lesser GABAergic innervation than large ones. The total synaptic covering and frequency were smaller on somata than on dendrites. However, the percentage of synaptic covering by GABA terminals was higher on cell bodies than on proximal dendrites.     

Glutamatergic components of the retrosplenial granular cortex in the rat

The ultrastructural characteristics, distribution and synaptic relationships of identified, glutamate-enriched thalamocortical axon terminals and cell bodies in the retrosplenial granular cortex of adult rats is described and compared with GABA-containing terminals and cell bodies, using postembedding immunogold immunohistochemistry and transmission electron microscopy in animals with injections of cholera toxin- horseradish peroxidase (CT-HRP) into the anterior thalamic nuclei. Anterogradely labelled terminals, identified by semi-crystalline deposits of HRP reaction product, were approximately 1 m in diameter, contained round, clear synaptic vesicles, and established asymmetric (Gray type I) synaptic contacts with dendritic spines and small dendrites, some containing HRP reaction product, identifying them as dendrites of corticothalamic projection neurons. The highest densities of immunogold particles following glutamate immunostaining were found over such axon terminals and over similar axon terminals devoid of HRP reaction product. In serial sections immunoreacted for GABA, these axon terminals were unlabelled, whereas other axon terminals, establishing symmetric (Gray type II) synapses were heavily labelled. Cell bodies of putative pyramidal neurons, containing retrograde HRP label, were numerous in layers V–VI; some were also present in layers I–III. Most were overlain by high densities of gold particles in glutamate but not in GABA immunoreacted sections. These findings provide evidence that the terminals of projection neurons make synaptic contact with dendrites and dendritic spines in the ipsilateral retrosplenial granular cortex and that their targets include the dendrites of presumptive glutamatergic corticothalamic projection neurons.     

Different kinds of axon terminals forming symmetric synapses with the cell bodies and initial axon segments of layer II/III pyramidal cells. I. Morphometric analysis

Summary An examination of material prepared for conventional electron microscopy has indicated that there are at least four different types of axon terminals forming symmetric synapses with the cell bodies and initial axon segments of layer II/III pyramidal cells in the rat visual cortex. One type of terminal synapses with the initial axon segment and it is derived from the chandelier cell. Because the location and features of these terminals allow them to be readily recognized, chandelier cell terminals were used to determine the extent of morphometric variability that can exist among terminals originating from one cell type. It was found that there is a wide range of mean synaptic vesicle size among chandelier terminals, so that calculated mean vesicle profile diameters for individual terminals can be between 32 and 39 run. Similar ranges of mean synaptic vesicle sizes also exist among populations of the other three axon terminal types. These terminal types are referred to as large, medium-sized, and dense terminals. The large terminals synapse with the cell bodies of layer II/III pyramids and their profiles often measure 1.5 × 0.8 m. The large terminals contain rather loosely packed pleomorphic vesicles and they frequently synapse with a second neuronal element. The medium-sized terminals are smaller, being 1.0 × 0.6–0.8 m in size, and their synaptic vesicles are usually more closely packed than those within the large terminals. The medium-sized terminals are the ones encountered most frequently on the cell bodies of pyramidal cells and they can also occur on the axon hillock and initial axon segment. The dense terminals are usually flattened against the cell body, and they contain rather rounded and closely packed synaptic vesicles, which often seem to be enmeshed in a rather dark cytoplasmic matrix. This matrix and the close packing of the vesicles makes these terminals appear to be more dense than the others. It is now necessary to determine the origins of the large, medium and dense terminals, and to ascertain if they all use GABA as their neurotransmitter.     

Vergleichende Mäuse-Immunisierungen mit zwei Influenza-A2-Adsorbat-Impfstoffen

Zusammenfassung Es wurden zwei Asia-Influenza-Impfstoffe in größeren Mäuseversuchsreihen vergleichend geprüft. Es ergab sich, daß der nach einem älteren Verfahren hergestellte Impfstoff (Impfstoff Hygiene-Institut), der das Influenzavirus aus Mäuselungen an Aluminiumhydroxyd adsorbiert enthält, sowohl im Mäuseschutzversuch als auch in der Bildung neutralisierender, hämagglutinations-hemmender und komplementbindender Antikörper einem Impfstoff aus neuerer Zeit (Handelsimpfstoff), der statt Aluminiumhydroxyd das-Aluminiumoxyd als Adsorbens enthält, überlegen ist. Es werden einige Gründe hierfür erörtert. Die Versuche lehrten ferner eindeutig, daß die einmalige ImpfstoffInjektion auch bei Adsorbat-Impfstoffen nicht ausreicht, um eine gute Immunität zu erzielen.     

Comparison of histologic types of primary testicular germ cell tumors with their metastases

Summary 61 autopsy cases with malignant germ cell testis tumors were examined. Both the primary tumors and their metastases were classified histologically according to the nomenclature of the WHO Panel on Testicular Tumours and to the modified nomenclature of the British Testicular Tumour Panel. The classification of the primary and metastatic tumor tissues is relatively easy to handle with both nomenclatures. The comparison of histological structures of the primary tumors with their metastases evoked a variety of deviations, depending on the tumor categories investigated and the nomenclature applied. The seminomas are a very homogenous tumor category usually metastasizing as seminoma. However, anaplastic seminomas can be indistinguishable from solid embryonal carcinomas. The distinct seminomas combined with nonseminomatous germ cell tumors do not seem to metastasize. From the point of view of histologic patterns of metastases and primary tumors, the embryonal carcinoma combined with teratoma i.e. teratocarcinoma (malignant teratoma intermediate) and the pure embryonal carcinoma (malignant teratoma undifferentiated) are not distinct entities. The term of malignant teratoma for these tumor types used by the British authors interprets these events more adequately, reflecting the occurrence of transitional types between teratoma and embryonal carcinoma supported by the appearance of different histologic types of metastases. Pure forms of choriocarcinoma are extremely rare. Yet in our cases of choriocarcinoma combined with other types, the metastases are always of the pure choriocarcinomatous type, and clinical courses were rapidly fatal in less than one year. The distinction of pure forms from combined forms of choriocarcinoma is not of great clinical relevance. 10% of our patients with metastatic germ cell tumor disease revealed testicular lesions referred to as so-called burned-out testis tumors. A tumor category of burned-out testis tumors is proposed.We wish to express our sincere thanks for providing additional histologic material to Prof. M. Aufdermaur, Luzern, Prof. H. Cottier, Bern, Dr. B. Egloff, Winterthur, Prof. F. Gloor, St. Gallen, Prof. H. A. Hienz, Krefeld, Prof. F. K. Kössling, Bremen, PD Dr. J. P. Mühlethaler, Aarau, Prof. G. Müller, Chur, Prof. P. Riniker, Locarno, Prof. E. Schairer, Ulm, PD Dr. R. Siebenmann, Zürich, and PD Dr. J. Torhorst, Basel.     

Retinal pigment epithelium melanin granules are phagocytozed by Müller glial cells in experimental retinal detachment

The ability of retinal Müller glial cells to perform phagocytosis in vivo is studied in a rabbit model of experimental retinal detachment where pigment epithelial cells are occasionally detached together with the neural retina. While macrophages and/or microglial cells phagocytoze most of the cellular debris at the sclerad surface of the detached retinae, some Müller cells accumulate melanin granules. The granules are virtually intact at the ultrastructural level, and are surrounded by a membrane. They are often located close to the sclerad end of the cells, but some are distributed throughout the outer stem process up to the soma. It is concluded that rabbit Müller cells in vivo are capable of phagocytosis and of transporting the phagocytozed material within their cytoplasm.     

Afferent neurons of the hypoglossal nerve of the rat as demonstrated by horseradish peroxidase tracing

Summary Cell bodies of sensory neurons of the rat's hypoglossal nerve were demonstrated by the somatopetal horseradish peroxidase (HRP) transport technique. Labelled perikarya were found within the second and third cervical spinal ganglia and in the vagal sensory ganglia.After application of HRP to the cut peripheral trunk of the hypoglossal nerve about 200 labelled cell bodies were counted in each animal. The vast majority of the axons from cervical spinal ganglion cells reach the hypoglossal nerve via the descending ramus (N. descendens hypoglossi). However, there may exist an additional pathway, probably via the cervical sympathetic trunk.Application of HRP to the medial and lateral end branches led to a labelling of much fewer spinal ganglion cells while the number of labelled vagal sensory neurons remained unchanged. Thus, it is suggested that the majority of the cervical afferents of the hypoglossal nerve originates within the extrinsic tongue musculature and the geniohyoid muscle, whereas the vagal afferents may perhaps derive exclusively from the intrinsic muscles.Histograms of the mean diameters of labelled cell bodies show a predominance of very small perikarya. This contrasts with the diameter distribution of sensory perikarya labelled after HRP application to nerves supplying other skeletal muscles. It is therefore assumed that the afferent component of the hypoglossal nerve is composed mainly of small-calibre axons.Supported by the Hartmann Müller-Stiftung, ZürichPart of this work was presented at the 74. Versammlung der Anatomischen Gesellschaft in Regensburg, March 1979     

Geschlechtsabhängiges Verhalten der Rattenschilddrüse

Zusammenfassung An 144 weiblichen und 171 männlichen Ratten wurden Fragen des Schilddrüsenverhaltens untersucht. Auf gleiches Körpergewicht der Tiere berechnet, leigt das Schilddrüsengewicht der Weibchen im Winter um 17% und im Sommer um 28% höher als das der Männchen. Beidmalig istp<0,001. Den nebenher gesicherten Winterzuwachs der Schilddrüse entwickeln Männchen stärker. Das 24 Std-PB¹³¹I des Serums liegt für Weibchen je nach Gruppe und Jahreszeit um 36% (p<0,001), um 38% (p<0,001) und um 47% (p<0,05) tiefer als für Männchen. In gleicher Richtung und ähnlich hoch signifikant unterscheidet sich das chemisch bestimmte Serum PBI: Mittelwerte und mittlere Fehler betragen für Weibchen 1,48 ± 0,13 g-% und für Männchen 2,10 ± 0,14 g-%; mit zunehmendem Lebensalter sinken die Werte ab; aus einer verschiedenen Steilheit dieses Absinkens ergibt sich schließlich noch Vergrößerung und weiter erhöhte Sicherung der Geschlechtsdifferenzen. Der chemisch bestimmte Jodgehalt der Schilddrüse beträgt je 10 mg Gewebe für Weibchen 6,58 ± 0,13 g und für Männchen 9,00 ± 0,68 g. Keinen deutlichen Unterschied zwischen Männchen und Weibchen ergab die¹³¹J-Ausscheidung des Körpers. Aus dem relativ höheren Schilddrüsengewicht der Weibchen wird auf deren höheres Blut-TSH geschlossen. Aus dem geringeren Jodgehalt der Schilddrüse bei einer Jodaufnahme gleich der der Schilddrüse des Männchens wird auf einen rascheren Jodumsatz der weiblichen Schilddrüse geschlossen. Hinsichtlich des geringeren Hormonspiegels im Blut trotz des rascheren Jodumsatzes in der Schilddrüse wird die Frage einer primär höheren Abbauquote des Schilddrüsenhormons im peripheren Gewebe des Weibchens behandelt. Übereinstimmungen der Befunde mit den Verhältnissen im menschlichen Organismus werden hervorgehoben. Für die naheliegende beziehung des kleineren Energieumsatzes der Frau auf das gefundene kleinere Blut-PBI werden Hinweise gebracht.Herrn Professor Dr.H. Lieb zum 80. Geburtstag gewidmet.     

Über das Vorkommen sogenannter cytopathogener Effekte in „normalen“ Zellkulturen

Zusammenfassung In anscheinend normalen Kulturen verschiedener Zellarten wurden cytopathogene Effekte gefunden, wie sie bisher nur durch als Viren bezeichnete Agentien (z. B. Schaumviren, Riesenzellenviren) und einige bekannte Virusarten in vitro erzeugt worden sind.Das Wirkungsspektrum des oder der in unseren Kulturen cytopathogenen X-Stoffe war erheblich. So weit bisher untersucht, erstreckte es sich auf Menschenzellen (HeLa-Krebszellen), Affenzellen (Nierenzellen; s.Falke 1957), Schweinezellen (Haut- und Nierenzellen), Rinderzellen (Zungenzellen) und Mäusezellen (Nieren-, Haut-, Karzinom- und Leukämiezellen).Auch das cytopathische Spektrum war breit. Es umfaßte 1. Einschlüsse: Rinderzunge, 2. Einschlüsse und Schaumbildung: Schweineniere, 3. Einschlüsse, Schaumbildung und abnorm erscheinende hyperplastische Zellen: Mäuseniere, Schweinehaut, 4. Einschlüsse, Schaumbildung und Riesenzellen: Menschenzellen (HeLa-Krebs), Mäusezellen (Haut, Karzinom, Leukämie).Einschlüsse und Schaumbildung kamen sowohl in ein- bis mehrkernigen als auch in Riesenzellen vor.Über die Natur des oder der in unseren Zellkulturen wirksamen X-Stoffe kann noch keine Aussage gemacht werden.Die vorliegenden Untersuchungen wurden mit Unterstützung der Deutschen Forschungsgemeinschaft ausgeführt.