Effect of insulin in vivo on the synthesis of free fatty acids (FFA) in chicken heart and skeletal muscle

Summary The effect of insulin on the synthesis of free fatty acids from glucose in the skeletal and heart muscles of chicken is examined. 10 min after glucose-(U-¹⁴C) administration, labeled free fatty acids (FFA) appeared in both skeletal and heart muscles. 0.75 IU of insulin kg^–1 b. wt significantly increased the labeled FFA at the 30, 60 and 120 min intervals, with a maximum at 60 min.     

The concentration of high molecular weight kininogen antigen in homogenates of various human tissues

Summary The concentration of high molecular weight kininogen, measured in human tissue homogenates, was 2–3 times higher in kidneys, adrenals and thyroid than in homogenates of lung, heart, liver and spleen. No measurable quantities of this protein were found in homogenates of brain and skeletal muscles.This work was supported by a grant from the Department of Medical Sciences of Polish Academy of Sciences.     

Aktivität der Aldolase und der Succinatdehydrogenase (SDH) in der weissen und roten Skelettmuskulatur junger und alter Ratten

Summary The activity of aldolase and succinatdehydrogenase (SDH) in white and red skeletal muscle of young (3–7 months) and old (20–30 months) rats has been determined. In addition also the SDH of liver was measured. The activity of aldolase is higher in white than in red muscles, while SDH shows a higher activity in red than in white muscles. The activity of aldolase is not influenced by ageing in white muscles, but decreased in red muscles by 23%. In old animals the activity of SDH is 34% less in white and 52% less in red muscles. In liver the activity is 44% less. The significance of these changes for the energy metabolism of skeletal muscle is discussed.     

The effect of exercise on protein turnover in isolated soleus and extensor digitorium longus muscles

Summary The rate of protein degradation was found to be increased in isolated soleus and extensor digitorum muscles of 60–80 g rats after exercise consisting of running for 120 min. These findings support the hypothesis that exercise causes an increase in skeletal muscle protein degradation, and that both red and white muscles are affected similarly.     

Die postnatale Entwicklung der Bursttätigkeit im Bulbus olfactorius des Kaninchens

Summary An investigation of the olfactory burst activity was undertaken in rabbits during 1–8 days of life. The bursts are already present at the first postnatal day (frequency 18 c/sec, amplitude 23µV). The values of the adult animal are reached at 8 days.     

Electrophysiological actions of chlorimipramine on guinea-pig ventricular fibres

Summary Chlorimipramine (CMI, 1×10^–5M to 7×10^–5M) decreased the amplitude, overshoot and rate of rise of ventricular action potentials and abolished the Ca-mediated action potentials elicited in guinea-pig papillary muscles. These results indicates that CMI inhibits the rise in sodium and calcium conductances during the cardiac action potential.     

Calcium and the contractile response to prostaglandin in the smooth muscle of guinea-pig stomach

Summary In the longitudinal smooth muscle of guinea-pig stomach, verapamil (10^–5 M) which showed marked suppression of high K-induced contractures, did not suppress the contractile response to PGE₁ (1.5×10^–9 to 10^–6 M) markedly. These results suggest that the contractile mechanism of PGE₁ in guinea-pig stomach may mainly depend on a release of bound Ca in the cell and partly depend on a Ca influx from the extracellular origin.     

Birefringence signals and tension development in single frog muscle fibres at short stimulus intervals

Summary The early large birefringence signal and mechanical activity were studied together in isolated single fibres of frog skeletal muscle with double stimulation at short stimulus intervals (2–60 msec) at room temperature and at 4–6°C. In all fibres tested, extra tension and additional birefringence signal in response to the second stimulus appeared simultaneously and suddenly upon increasing the stimulus interval. The shape of the stimulus-interval versus tension-development curve makes it highly improbable that subthreshold calcium release occurs at shorter stimulus intervals; therefore, tension development reliably reflects Ca-release in these experiments. In contrast to the report by Suarez-Kurtz and Parker, birefringence signal and calcium release are shown not to be dissociated by double stimulation. This result supports the hypothesis that the early large birefringence signal is an intrinsic indicator of calcium release from the sr during EC-coupling in skeletal muscle.     

Die Wirkung von Theophyllin auf den cellulären Ca-Stoffwechsel des Warmblüterherzens

Summary In isolated, electrically driven, left guineapig atria, theophylline (5×10^–4 g/ml) increased the rate of⁴⁵Ca uptake and release without affecting the total myocardial Ca content and the amount of exchangeable cellular Ca. In sheep and calf heart preparations, theophylline (10^–4–10^–3 g/ml) increased Ca inward current during excitation (as examined indirectly by Ca dependent changes of membrane potential in TTX-containing solutions) as well as tension development. It is concluded that the positive inotropic effect of theophylline in mammalian hearts is due to an increase in Ca influx during the excitation process.

---

---

Mit Unterstützung der Deutschen Forschungsgemeinschaft.     

Volume-dependent regulation of the respiratory burst of activated human neutrophils

The effect of incubation medium osmolality on the respiratory burst of human neutrophils was studied using luminol-dependent chemiluminescence (CL) as an indicator of burst activity. Neutrophils were stimulated with N-formyl-Met-Leu-Phe (FMLP), phorbol-12-myristate-13-acetate (PMA), the calcium ionophore A23187, thermoaggregated IgG (IgG_n), and opsonized zymosan (OZ). It was shown that increasing the osmolality of the incubation medium from 320 up to 420 mosM decreased the A231870 and OZ-induced CL responses by 90%. Under the same conditions PMA-, FMLP- and IgG_n-induced CL responses were decreased by 40–60%. A decrease of osmolality to 200 mosM resulted in a 2–3 fold decrease of the A23187-, PMA- and FMLP-induced CL and in a 60–80% increase of OZ- and IgG_n-induced CL. It is suggested that osmolality-mediated alteration of cell volume is an important mechanism for regulating neutrophil activity.     

Über eine bei jungen Kaninchen während Erregung auftretende hochfrequente mesenzephale Bursttätigkeit

Summary In the mesencephalon of young rabbits (11–45 days old), a distinct pattern could be elicited by emotional activation: it consists of high-frequency bursts (48–70 c/sec, duration up to 150 msec), superimposed on phase-locked slow waves.     

Is there a functional large intestine in the ferret?

Summary The intestine of the ferret (Putorius furo) is unusual in that there is no external anatomical division between ileum and colon. Up to 8–10 cm from the anus the electrical activity was organized into migrating myoelectric complexes typical of the small intestine. At this point the pattern of electrical activity changed abruptly to that characteristic of the colon, namely short and long spike burst activity. Histological examination showed that at this point the muscular layers were interupted by a band of connective tissue sufficient to permit the functional autonomy of the last part of the intestine.Acknowledgments. The authors are grateful to V. Rayner for helpful discussion and criticism. They acknowledge financial support received from INRA (Department of Veterinary Research).     

Fluorometrische bestimmung von mikromengen calcium in muskelgewebe

Summary A method for fluorometric estimation of micro-amounts of calcium (about 10 nEq./sample) in biological materials using calcein as indicator. Its applicability to heart muscle specimens (6–100 mg wet weight) and its limitation by interfering substances are described.     

The use of microtiter plates for the simple and sensitive determination of insulin by an ELISA method

Summary A method of insulin determination using a commercially available ELISA kit was modified for use in microtiter plates. The adapted assay, based on the binding of procine anti-guinea pig insulin antibodies to microtiter plates and insulin-peroxidase conjugate as displacer, is sensitive between 0.5 and 30 ng/ml. Since it uses only 10–40 l of sample material it enables the determination of 5–100 pg of insulin. The rapid (5–6 h), automatable, reproducible and reliable assay makes it possible to determine many samples in a short time.     

Concept of an extracellular regulation of muscular metabolic rate during heavy exercise in humans by psychophysiological feedback

Efferent motor signals to skeletal muscles concern not only the space/time pattern of motion, but also the setting of muscular performance and through this the control of the current metabolic rate. For an optimal adjustment of metabolic rate during heavy exercise — e.g. in athletic competitions — a feedback control system must exist, including a programmer that takes into consideration a finishing point (teleoanticipation). The presented experiments, using Borg's scale, indicate the existence and functioning of a system for optimal adjustment of performance during heavy exercise and the relevance of teleoanticipatory effects. Thus motor learning includes not only somatosensory control, but also metabolic control. With regard to migratory birds, such metabolic control would have to operate in the individual as well as in the migrating flock as a whole.     

Die Abhängigkeit der Ca++-Aufnahme isolierter Mitochondrien des Herzmuskels von der Na+-und K+-Konzentration als mögliche Ursache der inotropen Digitaliswirkung

Summary In isolated mitochondria of heart muscle from rabbits and oxen there is, under suitable conditions, an accumulation of Ca⁺⁺, which is significantly enhanced by elevating the K⁺/Na⁺ quotient of the incubation medium. K-strophanthine (10^–5–10^–7) does not influence the accumulation of Ca⁺⁺ by the mitochondria of heart muscle. Therefore the intracellular increase in exchangeable Ca⁺⁺ observed after digitalis-glycosides could be explained by a decrease of the intracellular K⁺/Na⁺ quotient, which is caused by inhibition of the membrane ATPase and diminishes the capacity for Ca⁺⁺ accumulation in mitochondria.     

Respiratory burst in peritoneal exudate cells in response to a modified tuftsin

Intraperitoneal administration of tuftsin-M [Thr–Lys–Pro–Arg–NH–(CH₂)₂–NH–CO–C₁₅H₃₁] to Balb/C mice has been shown to induce a respiratory burst in the peritoneal exudate cells. The macrophages exhibited enhanced levels of O₂ ^–, H₂O₂, NADPH oxidase and myeloperoxidase, but the activities of superoxide dismutase, catalase and glutathione peroxidase remained virtually unchanged. The magnitude of the oxidative burst depended directly on the dose of tuftsin-M; higher activity was observed at higher doses of the peptide. Tuftsin-M enhanced the generation of both O ₂ ^– and H₂O₂ under in vitro conditions, as did phorbol myristate acetate. These results suggest that tuftsin-M could enhance non-specific defence against infections by activating the macrophages.     

Lack of pressor effect of dopamine in the pentobarbital-anesthetized rat

Summary The blood pressure and heart rate responses to intravenous dopamine infusion at 2.5, 5.0 and 10.0 g·min^–1·100 g^–1 were studied in conscious and pentobarbital-anesthetized Sprague — Dawley rats. In the conscious rats, dopamine caused a significant dose-related increase in the mean arterial blood pressure which was abolished in the anesthetized rats. The heart rate increased significantly only at the highest dose infused. The responses to equipressor doses of noradrenaline (40 ng·min^–1·100 g^–1) and phenylephrine (1.0 g·min^–1·100 g^–1) were also suppressed in the anesthetized rats. The results suggest that pentobarbital anesthesia depresses the blood pressure response to dopamine infusion in the rat through a depression of activation of alpha-adrenoceptors.16 June 1986     

Prostaglandin A2 (PGA2) increases the coronary vascular resistance in the guinea-pig isolated heart preparation

Summary Prostaglandin A₂ (PGA₂) in concentrations of 1.5·10^–8 to 3·10^–6 M was found to produce concentration-dependent increase in the coronary vascular resistance of the guinea-pig isolated heart without alterations in myocardial contractile force and oxygen consumption.Supported by the Deutsche Forschungsgemeinschaft.     

Activité antifibrillante chez l'animal d'un nouveau dérivé de la phényl-éthylamine

Summary A new synthetic phenyl-ethyl-amine derivative, the 2-[N- (3, 4-methylen-dioxyphenylethyl)-methylaminomethyl]-tetrahydrofuran, No. 11 081, exhibits a strong protective effect against cardiac fibrillation and arrhythmias produced by various experimental methods: against fibrillation due to aconitine 3 × 10^–8 on the isolated cat's heart, it is active in a concentration of 10^–6–2 × 10^–6. Against cardiac arrhythmias produced in the cat by adrenaline + CHCl₃ or cyclopropane, it shows a protective effect by 5–10 mg/kg i.v. and even perorally by 50 mg/kg. In these tests, the antifibrillatory activity of the new compound seems to be roughly the same as that of -fagarine, and higher than that of procaine.

---

---

9^e communication sur les dérivés des alcoylène-imines; 8^e communication, cf. Exper.10, 261 (1954).