VOLUME 34 NUMBER 3 February 1972
Hemodynamic Effects of Beta Adrenergic Receptor Stimulant and Blockade
Hemodynamic Effects of Isoproterenol after Propranolol
IWAO FUKUTA
pg(s) 199 - 212
The effects of isoproterenol and propranolol on the hemodynamics were evaluated in dogs for the purpose of their clinical application in the management of cardiovascular surgical patients.
In dogs receiving 0.002 mg/kg of isoproterenol intravenously with one shot, marked positive inotropic and chronotropic responses were achieved in 5 seconds and returned to the control values in 5 minutes.
Heart rate, myocardial contractility, coronary blood flow and cardiac output increased markedly, but blood pressure decreased by about 50%.
In dogs receiving the same dose of isoproterenol infusion over 15 minutes, similar changes were achieved, though milder. The effect remained stable during infusion. Isoproterenol iufusion was thought to be superior to injection as one shot in clinical application.
In dogs receiving 0.2 m/kg of propranolol intravenously, depressing inotropic and chronotropic effects appeared in a few minutes. Myocardial contractility, cardiac output and heart rate decreased, but stroke volume increased. When 0.002 mg/kg of isoproterenol was injected after propranolol, the effects of isoproterenol were milder. The effect of isoproterenol to decrease blood pressure was prevented by propranolol.
Isoproterenol infusion after propranolol injection resulted in a significant increase in myocardial contractility and a less in heart rate by overcoming the effects of propranolol with a far less increase in myocardial oxygen consumption.
In dogs receiving 0.002 mg/kg of isoproterenol intravenously with one shot, marked positive inotropic and chronotropic responses were achieved in 5 seconds and returned to the control values in 5 minutes.
Heart rate, myocardial contractility, coronary blood flow and cardiac output increased markedly, but blood pressure decreased by about 50%.
In dogs receiving the same dose of isoproterenol infusion over 15 minutes, similar changes were achieved, though milder. The effect remained stable during infusion. Isoproterenol iufusion was thought to be superior to injection as one shot in clinical application.
In dogs receiving 0.2 m/kg of propranolol intravenously, depressing inotropic and chronotropic effects appeared in a few minutes. Myocardial contractility, cardiac output and heart rate decreased, but stroke volume increased. When 0.002 mg/kg of isoproterenol was injected after propranolol, the effects of isoproterenol were milder. The effect of isoproterenol to decrease blood pressure was prevented by propranolol.
Isoproterenol infusion after propranolol injection resulted in a significant increase in myocardial contractility and a less in heart rate by overcoming the effects of propranolol with a far less increase in myocardial oxygen consumption.
Studies on the Structure and Function of Biological Membrane System
II. Configurational Changes of Mitochondria in situ Correlating to Functional States
YOHEI TAKAHASHI
pg(s) 213 - 226
Configurational changes of the mitochondrial inner ·membrane system were examined ultrastructurally and biochemically. Mitochondria in intact heart muscle appeared predominantly in a so-called "orthodox" mode. On the other hand, the mitochondria isolated from liver or heart muscle showed a so-called "aggregated" mode.
Many authors who have examined extensively isolated mitochondria found that they underwent ultrastructural changes coupled with their functional metabolic states, corresdonding to the surrounding conditions such as substrates, Pi, nucleotides or uncouplers.
Intact heart muscles were fixed by perfusion with glutaraldehyde solutions, and two types of configurational states of mitochondria were found. The first type of mitochondria showed an irregular and relatively straight arrangement of the inner membrane system. The second had an angular and regular configuration. Ehrlich ascites tumor cells also exhibited the twisting and waving con- figuration of mitochondrial inner membrane when fixed at the state of respiratory inhibition induced by addition of glucose. Mitochondria of fasted ascites cells showed an irregular configuration.
Mitochondria in the rough homogenates of rat heart muscle had morphologically a transitional structure between isolated mitochondria and in situ ones. Mitochondria in the homogenates fixed at various functional metabolic states showed particular configurational changes correlating to their functional states in both "orthodox" and "aggregated" modas.
From in vitro experiments, the angular or twisted configuration of the inner membrane of mitochondria was found to be induced by oxidizable substrates and Pi. As intact cells possess Pi endogenously, the mitochondria in situ are considered to have two different configurations.
Many authors who have examined extensively isolated mitochondria found that they underwent ultrastructural changes coupled with their functional metabolic states, corresdonding to the surrounding conditions such as substrates, Pi, nucleotides or uncouplers.
Intact heart muscles were fixed by perfusion with glutaraldehyde solutions, and two types of configurational states of mitochondria were found. The first type of mitochondria showed an irregular and relatively straight arrangement of the inner membrane system. The second had an angular and regular configuration. Ehrlich ascites tumor cells also exhibited the twisting and waving con- figuration of mitochondrial inner membrane when fixed at the state of respiratory inhibition induced by addition of glucose. Mitochondria of fasted ascites cells showed an irregular configuration.
Mitochondria in the rough homogenates of rat heart muscle had morphologically a transitional structure between isolated mitochondria and in situ ones. Mitochondria in the homogenates fixed at various functional metabolic states showed particular configurational changes correlating to their functional states in both "orthodox" and "aggregated" modas.
From in vitro experiments, the angular or twisted configuration of the inner membrane of mitochondria was found to be induced by oxidizable substrates and Pi. As intact cells possess Pi endogenously, the mitochondria in situ are considered to have two different configurations.
Optimal Magnification Ratio of Direct Macroradiography in High Magnification
Modulation Transfer Function Study on System Combined with Intensifying Screen-Film and Object
YOSHIO AYAKAWA
pg(s) 227 - 240
Calculation of the composite modulation transfer function (MTF) of macroradiography in high magnification conducted with an X-ray tube having a very fine focal spot of 50 µ was performed with the purpose of obtaining the optimal magnification ratio.
The optimal magnification ratio of a macroradiogram taken without the object of scatterer was 4-fold when a Fuji KX medical X-ray film combined with fine definition intensifying screen of Kyokko FS was used, 5-fold with medium speed screen of Kyokko MS and 6-fold with high speed screen of Kyokko HS. The optimal magnification ratio was 8-fold regardless of the kind of intensifying screen-film system when the experiment was made with a water phantom of 5-15 em in thickness as scatterer.
It was indicated from MTFs of macroangiograms of various magnifications obtained in animal experiments that the image quality of the macroangiogram of 6- or 8-fold magnification was superior to those of 2-, 4-, 10- and 15-fold ones.
It was concluded from the examination of macroangiograms of animals (the part of the rabbit examined was 3-5 em thick) and macrolymphograms of patients (the examined part was 13 em thick) that the macroradiogram of 6- or 8-fold magnification produces better findings of the fine structure of vessels than macroradiogram of other magnifications. The results accorded well with those obtained by phantom experiments with water of 5-15 em in thickness as scatterer.
The optimal magnification ratio of a macroradiogram taken without the object of scatterer was 4-fold when a Fuji KX medical X-ray film combined with fine definition intensifying screen of Kyokko FS was used, 5-fold with medium speed screen of Kyokko MS and 6-fold with high speed screen of Kyokko HS. The optimal magnification ratio was 8-fold regardless of the kind of intensifying screen-film system when the experiment was made with a water phantom of 5-15 em in thickness as scatterer.
It was indicated from MTFs of macroangiograms of various magnifications obtained in animal experiments that the image quality of the macroangiogram of 6- or 8-fold magnification was superior to those of 2-, 4-, 10- and 15-fold ones.
It was concluded from the examination of macroangiograms of animals (the part of the rabbit examined was 3-5 em thick) and macrolymphograms of patients (the examined part was 13 em thick) that the macroradiogram of 6- or 8-fold magnification produces better findings of the fine structure of vessels than macroradiogram of other magnifications. The results accorded well with those obtained by phantom experiments with water of 5-15 em in thickness as scatterer.
Studies on Structure and Function of the Biological Membrane Systems
III. The Modes of Action of Corticosterones on The Isolated Subcellular Membranes
YOSHIAKI ITATSU
pg(s) 241 - 258
The modes of action of corticosterones on the isolated subcellular compartments of mitochondria, lysosomes and red cell ghosts were studied by using chiefly hydrocortisone and 11-desoxycorticosterone (11-DOC) at higher concentrations than physiological ones (below 10-6 M). The changes of those biological membrane systems were examined both electron-microscopically and biochemically. The ultrastructural alterations of the membrane structures corresponded to the changes of the enzyme activities in both radical and ion reactions which were directed or controlled in the subcellular membranes.
10-4-10-3 M 11-DOC induced the following changes; (a) respiratory inhibition and uncoupling of oxidative phosphorylation in mitochondria, (b) configurational changes in mitochondrial inner membrane to orthodox type involving swelling of mitochondria, (c) release of acid hydrolytic :enzymes and fragmentation of lysosomal membranes, (d) inhibition of activities of Na+, K+-dependent or Mg2+-activated ATPase, (e) dislocation and micelles formation of lipid in the membrane and electron dense body formation on the surface of the membrane, (f) fusion and aggregation of membrnes.
Hydrocortisone or cholesterol showed similar effects, to less degrees, as a result of non specific actions at high concentrations (10-3 M), but hydrocortisone had a tendency to stabilize the lysosomal membranes. The different mode of action of 11-DOC and hydrocortisone on the membrane may induce the different changes of the high ordered structures in the membraneous polymers which are composed of proteins and lipids.
10-4-10-3 M 11-DOC induced the following changes; (a) respiratory inhibition and uncoupling of oxidative phosphorylation in mitochondria, (b) configurational changes in mitochondrial inner membrane to orthodox type involving swelling of mitochondria, (c) release of acid hydrolytic :enzymes and fragmentation of lysosomal membranes, (d) inhibition of activities of Na+, K+-dependent or Mg2+-activated ATPase, (e) dislocation and micelles formation of lipid in the membrane and electron dense body formation on the surface of the membrane, (f) fusion and aggregation of membrnes.
Hydrocortisone or cholesterol showed similar effects, to less degrees, as a result of non specific actions at high concentrations (10-3 M), but hydrocortisone had a tendency to stabilize the lysosomal membranes. The different mode of action of 11-DOC and hydrocortisone on the membrane may induce the different changes of the high ordered structures in the membraneous polymers which are composed of proteins and lipids.
Ultrastructural Demonstration of Excessively Accumulated free Cholesterol in the Hepatic Cells in a Case of So-Called Phospholipidosis
HISANDO KOBAYASHI and HISASHI TAUCHI
pg(s) 259 - 266
Histological, histochemical, biochemical and electron microscopic studies were performed on the liver of an autopsy case of drug-induced lipidosis.
The important electron microscopic findings were numerous myelin figures and aggregates of fibrils network in the hepatic cells. It was noted that the fibrils in aggregates of network structure communicated with the myelin figures. The appearance of the changes could be dosely related to the mitochondria.
The electron microscopic specimens immersed in digitonin solution showed that free cholesterol excessively accumulated in the hepatic cells, and also appeared in the myelin figures and aggregates of fibrils network as one of the chemical composition.
Histochemical examination of the liver, spleen, lymph~odes.and bone marrow indicated the phospholipid deposition in general organs.
The important electron microscopic findings were numerous myelin figures and aggregates of fibrils network in the hepatic cells. It was noted that the fibrils in aggregates of network structure communicated with the myelin figures. The appearance of the changes could be dosely related to the mitochondria.
The electron microscopic specimens immersed in digitonin solution showed that free cholesterol excessively accumulated in the hepatic cells, and also appeared in the myelin figures and aggregates of fibrils network as one of the chemical composition.
Histochemical examination of the liver, spleen, lymph~odes.and bone marrow indicated the phospholipid deposition in general organs.