0000000000280498
AUTHOR
P. Wendling
Red Cell Interactions with the Microcirculation
We have measured RBC velocity profiles for mammalian arterioles and venules from high-speed cinematographic motion pictures. Measurements were made at 320× and 400× optical magnification over an averaging time period of 10 ms. In vivo profiles are uniformly nonsymmetrical, the RBCs exhibit rotation, and they frequently deviate sidewise from the overall axial direction of motion. In general, this is more pronounced on the venous side. Since all of the profiles are time variant and the average values are synchronous with the midstream velocity, individual RBC velocities will vary about the average. Profiles become more blunted in vessels with smaller diameters. In vessels below 16 μm diameter…
In vivo investigations on microcirculatory disturbances induced by crenated erythrocytes following norepinephrine application
Using a special apparatus for high resolution cinephotomicrography, which allows simultaneous observation and recording of microcirculatory changes, alterations in blood flow patterns and in red cell shape during norepinephrine acting have been studied. Under physiological conditions, and during slowing of capillary blood flow due to gradual removing of 20–25% of the circulating blood volume, the normal red cells are extremely deformable while passing through mesenteric capillaries. After application of norepinephrine a general arteriolar constrictive response in the bowel wall occurs, causing a further slowing of the capillary blood flow in the mesentery. Under these circumstances the eryt…
Mesenterico-caval shunt in rats
A microsurgical technique for mesenterico-caval shunting in the rat is described. The method results in a partial blood drainage from the upper abdominal content whereas the blood of the mesenteric vein is shunted to the inferior caval vein. Controls were undertaken after 1 and 3 weeks, either visually or radiologically. Twenty-two of 26 surviving animals showed patency of the shunt. All animals had undisturbed blood supply to the portal stump.
Heterogeneous Oxygenation of Rectal Carcinomas in Humans: A Critical Parameter for Preoperative Irradiation?
The surgical treatment of rectal carcinoma in humans is often combined with irradiation. However, the efficacy of this latter treatment modality is crucially influenced by the oxygenation status of the tumor tissue to be treated. Therefore, the knowledge of the O2 supply to the tumor tissue is a decisive prerequisite for the assessment of the efficiency of radiotherapy.
Experimentelle und theoretische Untersuchungen der intralienalen Mikrozirkulation beim Kaninchen
1. Bei 57 spontanatmenden Kaninchen wird in Ketaminnarkose mit Hilfe der85Kr(β)-Auswaschtechnik nach Stosinjektion des gelosten Indikators in die Aorta die regionale Milzdurchblutung gemessen. 2. Bei der normalen, unbeeinflusten Milzin situ besteht im Bereich von 65–125 mm Hg eine lineare Abhangigkeit der regionalen Milzdurchblutung vom arteriellen Mitteldruck (2p < 0,001). Bei einem mittleren Druck von 97 mm Hg betragt die mittlere Milzdurchblutung 1,23 ml/g/min. 3. Nach totaler Obstruktion der offenen Strombahn durch Applikation rigider Spharocyten ist die Durchblutung im gleichen Blutdruckbereich unabhangig vom arteriellen Mitteldruck. Nach Ausschaltung der offenen Strombahn betragt die …
Splenic respiratory gas exchange and glucose uptake in patients with splenomegaly in hypersplenism and Hodgkin's disease.
Blood samples are taken from the splenic artery, vein and pulp of patients suffering from Hodgkin's disease (n=10) or hypersplenism (n=7) and undergoing splenectomy. In these samples, the relevant parameters of the respiratory gas exchange as well as glucose and lactate concentrations are determined. In hypersplenism (mean splenic wet weight: 543 g) the mean oxygen consumption of the splenic tissue amounts to 0.9 ml O2/100 g/min taking into account a mean splenic blood flow of 80 ml/100 g/min. The glucose uptake and the lactate release are 9 mg/100 g/min and 5.5 mg/100 g/min, respectively. These values are in close agreement with the results obtained in the normal and undisturbed spleen in …
Atemgaswechsel und Glucoseaufnahme der menschlichen Milzin situ
Bei 16 Patienten mit lymphoproliferativen Erkrankungen, mit essentieller Thrombozytopenie oder hereditarer Spharocytose werden vor der Splenektomie Blutproben aus der Milzarterie, -vene und -pulpa entnommen und die relevanten Parameter des Atemgaswechsels sowie Glucose- und Lactatkonzentrationen bestimmt. Die eingehende Untersuchung der operativ entfernten Milzen zeigte in keinem Fall histopathologische Veranderungen. Unter Zugrundelegung einer mittleren Milzdurchblutung von 100 ml/100 g/min wahrend der Narkose errechnet sich ein mittlerer O2-Verbrauch des Milzgewebes von 1,1 ml/100 g/min. Die Glucose-Aufnahme und die Lactatfreisetzung betragen 9 mg/100 g/min bzw. 5,2 mg/100 g/min. Niedrige…