Veränderungen der Serum-Antiotensinogen-Konzentration bei akuter Hepatitis und Lebercirrhosen

Zusammenfassung Die Angiotensinogen-Konzentration im Serum ist in der akuten und Abheil-Phase der Hepatitis (n=16) auf durchschnittlich 72–81% der Norm herabgesetzt. Bei 19 kompensierten und 10 dekompensierten Lebercirrhosen findet sich eine Substratverminderung auf 50%. Korrelationsstatistisch ist ein Zusammenhang zum Serum-Bilirubin, Albumin und Gesamtprotein sowie zur Transaminase-Aktivität weder für die Hepatitis- noch für die Cirrhose-Gruppe nachweisbar. Ebenso ergibt sich bei Lebercirrhosen keine statistisch gesicherte reziproke Abhängigkeit zwischen Serum-Renin-Aktivität und Angiotensinogen-Spiegel. Auch bei hochgradiger Funktionseinschränkung ist die Leber noch zur Substratsynthese befähigt. Ein totaler Schwund ist selten.     

Appearance of high-frequency alpha band with disappearance of low-frequency alpha band in EEG is produced during voluntary abdominal breathing in an eyes-closed condition

This study examined the effects of voluntary abdominal breathing (VAB) on the electroencephalogram (EEG) in 22 healthy subjects. VAB was characterized by prolonged rhythmic contraction of abdominal muscles for 20 min in an eyes-closed condition. The breathing rate was instructed to be very slow, i.e., 3-4 breaths/min (inspiratory time for 6-8s and expiratory time for 9-12s). A low-frequency alpha band appeared immediately after eye closing, but it later disappeared and was replaced by a new development of a high-frequency alpha band 4-5 min after the onset of VAB. The subjects had a feeling of vigor-activity with a tendency of reduced anxiety during and/or after VAB, as assessed by POMS and STAI questionnaire scores. On the other hand, during resting in the eye-closed condition, the disappearance of the low-frequency alpha band was replaced by the occurrence of a theta/delta band. The subjects became drowsy in this condition. We therefore conclude that the increase in high-frequency alpha activity is linked to the state of vigor-activity with a tendency of reduced anxiety. Since the urinary serotonergic level significantly increased after the VAB, we suggest that the serotonergic neurons within the brain may produce the changes in the EEG patterns.     

An immature rat lymphocyte marker CD157: striking differences in the expression between mice and rats

We have established a novel monoclonal antibody that recognises mouse and rat CD157, and uncovered striking differences in both the level and stage of expression of this antigen in the primary lymphoid organs between these two species. Unlike mouse, the majority of rat thymocytes express CD 157. SHR and WKY rats were the exception, having unusually low levels (similar to those of the mouse) of these cells. However, in both species, a subset of CD3- CD4- CD8- thymocytes exhibited high levels of CD157. Surprisingly, these CD157high cells temporarily upregulated MHC class I molecules in both species. Furthermore, a third of CD157high rat thymocytes were CD45RC+, a marker found on immature thymocytes with regenerative capacity. Examination of the bone marrow lymphoid population shows that the expression of rat CD157 is largely observed at the CD45R+ IgM- pre-B-II cell stage, and unlike mouse, extension of expression into the IgM+ immature B cell stage was marginal. Similar to CD157high immature thymocytes, these immature B cells also expressed high levels of MHC class I. With the exception of the LEC, SHR and WKY rat strains, which have three- to four-fold less CD157+ bone marrow myeloid cells, percentages of these cells are similar between these two species. Thus, marked differences in the level and stage(s) of CD157 expression on lymphoid cells in mouse and rat indicate that CD157 may not, as previously thought, have a direct role in T or B cell differentiation.     

Analysis of proliferating biliary epithelial cells in human liver disease using a monoclonal antibody against DNA polymeraseα

The proliferative activity and ultrastructural characteristics of proliferating biliary epithelial cells were analysed immunohistocytochemically in 39 biopsied liver specimens from patients with acute viral hepatitis, chronic hepatitis and liver cirrhosis using a monoclonal antibody against DNA polymerase (DNA-PA). In acute viral hepatitis with perivenular confluent necrosis, proliferation of typical bile ducts was found frequently in portal areas. In chronic aggressive hepatitis and cirrhosis, ductular proliferation of both typical and atypical forms was found in enlarged portal and periportal areas and in confluent necrotic areas. The number of proliferating biliary epithelial cells that stained positive for DNA-PA was small. There were very few positively stained cells in atypical bile ducts in confluent necrotic areas of cirrhosis. Atypical bile ducts seen in chronic aggressive hepatitis, cirrhosis and acute hepatitis with confluent necrosis were positively stained for both cytokeratins 8 and 19. In cirrhosis, the number of stained biliary epithelial cells in typical bile ducts was larger than the number of such cells in atypical bile ducts (P< 0.01). By electron microscopy, the cells positively stained for DNA-PA were mostly so-called clear cells with irregular nuclei containing coarse nucleoplasm, and a few small cells with scanty cytoplasm and few organelles.     

Atypical Glomus Tumor in the Mediastinum: A Case Report with Immunohistochemical and Ultrastructural Studies

A case is reported of atypical glomus tumor occurring in the posterior inferior mediastinum of a 26-year-old woman complaining of severe back pain. The tumor was composed of atypical small, round tumor cells with scattered mitotic figures. In addition to sheet-like, diffuse proliferation of the tumor cells, some areas of the tumor contained small “glo-moid” cells arranged in organoid and hemangiopericytoma-like patterns. Immunohistochemically, many tumor cells were positive for muscle-type actins and a few cells were focally positive for desmin. Ultrastructural studies revealed smooth muscle features of tumor cells, that is, pinocytotic vesicles, external laminas, dense plaques, and occasional thin filaments with dense bodies. The patient remained well for 5 years and 4 months after the operation without additional radiation and chemotherapy. The tumor was diagnosed as an atypical, or low-grade malignant, glomus tumor morphologically. It seems important to recognize the presence of this type of tumor in sites other than extremities and to differentiate it from other malignant small, round cell tumors.     

Monosynaptic inputs from the nucleus tractus solitarii to the laryngeal motoneurons in the nucleus ambiguus of the rat

The cricothyroid (CT) and the posterior cricoarytenoid (PCA) muscles in the larynx are activated by the laryngeal motoneurons located within the nucleus ambiguus; these motoneurons receive the laryngeal sensory information from the nucleus tractus solitarii (NTS) during respiration and swallowing. We investigated whether the neurons in the NTS projected directly to the laryngeal motoneurons, and what is the synaptic organization of their nerve terminals on the laryngeal motoneurons using the electron microscope. When wheat germ agglutinin-conjugated horseradish peroxidase (WGA-HRP) was injected into the NTS after cholera toxin subunit B-conjugated HRP (CT-HRP) was injected into the CT muscle or the PCA muscle, the anterogradely WGA-HRP-labeled terminals from the NTS were found to directly contact the retrogradely CT-HRP-labeled dendrites and soma of both the CT and the PCA motoneurons. The labeled NTS terminals comprised about 4% of the axosomatic terminals in a section through the CT motoneurons, and about 9% on both the small (PCA-A) and the large (PCA-B) PCA motoneurons. The number of labeled axosomatic terminals containing round vesicles and making asymmetric synaptic contacts (Gray’s type I) was almost equal to that of the labeled terminals containing pleomorphic vesicles and making symmetric synaptic contacts (Gray’s type II) on the CT motoneurons. The labeled axosomatic terminals were mostly Gray’s type II on the PCA-A motoneurons, while the majority of them were Gray’s type I on the PCA-B motoneurons. These results indicate that the laryngeal CT and PCA motoneurons receive a few direct excitatory and inhibitory inputs from the neurons in the NTS. Accepted: 2 June 2000     

Effect of maximal arm exercise on skin blood flux in the paralyzed lower limbs in persons with spinal cord injury

 The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC) were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen uptake and peak heart rate was 1.41 ± 0.22 l · min^–1 and 171.6 ± 19.2 beats · min^–1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest. These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE. Accepted: 12 September 1996     

Hepatische Extraktion und Clearance von Renin bei Lebercirrhosen

Zusammenfassung Bei 14 kompensierten und 8 dekompensierten Lebercirrhosen wurden Vergleichsbestimmungen der Renin-Aktivität (RA) im arteriellen und Lebervenenblut (Methode Kaneko et al.) durchgeführt. Die errechnete hepatische Renin-Extraktion (HE %) ist im Gegensatz zu Befunden anderer bei Cirrhosekranken nicht aufgehoben. Die Einzelwerte sind weit gestreut, die HE beträgt bei kompensierten Cirrhosen durchschnittlich 17,8±17,3%, bei dekompensierten Cirrhosen 30,5±5,8%. Ein signifikanter Unterschied der HE zu einer Vergleichsgruppe Hochdruckkranker (Mittelwert 28,5±20,4%,n=20) besteht nicht (p>0,05 bzw.>0,4).Aus den bei der Mehrzahl der Cirrhosekranken durchgeführten Bestimmungen leberhämodynamischer Größen geht hervor, daß die Renin-Extraktion der Tendenz nach mit dem Lebervenenverschlußdruck ansteigt (r=–0,393,p>0,05). Zum hepatischen Plasmafluß, bestimmt mit der Indocyaningrün-Methode, ergibt sich eine umgekehrte, statistisch allerdings nicht gesicherte Beziehung (r=–0,427,p>0,05). Es wird geschlossen, daß die hepatische Extraktion von Renin bei Lebercirrhosen vermutlich durch die intrahepatische Passagezeit beeinflußt wird.Unter Berücksichtigung der für die Vergleichsgruppe errechneten hepatischen Renin-Clearance (HRC) von 292±178 ml/min ist die HRC bei kompensierten Cirrhosen auf 68%, bei dekompensierten Cirrhosen auf 42,5% herabgesetzt. Im Rahmen der komplexen Regulationsstörung des Renin-Angiotensin-Systems bei fortgeschrittenen Lebercirrhosen dürften danach nicht allein Änderungen der renalen Sekretion, sondern außerdem eine Einschränkung der hepatischen Renin-Clearance für die Aufrechterhaltung einer erhöhten Plasma-Enzym-Aktivität von Bedeutung sein.     

Renin-Substrat-(Angiotensinogen-)Konzentration im maternen und fetalen Blut

Zusammenfassung Bei 18 Schwangeren wurden unter der Geburt Vergleichsbestimmungen der Angiotensinogen-Konzentration und der Renin-Aktivität (modifiz. Methode nach Kaneko) im mütterlichen peripher-venösen und Nabelschnurblut durchgeführt.Im fetalen Serum ist die Angiotensinogen-Konzentration auf durchschnittlich 1440 ± 543 ng/ml gegenüber 3622 ± 1312 ng/ml im mütterlichen Serum (p<0,001) herabgesetzt. Dagegen liegt der fetale Angiotensinogengehalt, bezogen auf die Erwachsenen-Werte Nichtgravider (1115 ± 178 ng/ml) um 39% (p<0,05) erhöht.Die Renin-Aktivität ist im mütterlichen Serum mit 15,7 ± 8,7 ng/ml/4 Std signifikant (p<0,05) gegenüber dem fetalen Blut (31,4 ± 28,2 ng/ml/4 Std) herabgesetzt.Es wird geschlossen, daß die fetale Leber in hohem Maße Angiotensinogen synthetisieren kann. Der mögliche stimulierende Einfluß mütterlicher oder placentarer Oestrogene auf die hepatische Biosynthese wird erörtert. Unter Berücksichtigung des Konzentrationsgradienten ist mit einem placentaren Übertritt von Angiotensinogen zur fetalen Seite nur in geringem Maße zu rechnen.