摘要:

Summary.Comparative biochemical studies have been performed in hibernating hedgehogs in January and March and in non‐hibernating hedgehogs in June.Red blood corpuscles and hemoglobin level were lower in March in comparison to January and June when the difference was slight. Also the hematocrit values were lower in March compared with January, while the values in June lay between these. The leucocytes decreased during hibernation but the differential leucocyte count did not change markedly except for the eosinophils which decreased comparatively more than the other leucocytes. Also reticulocytes decreased but blood platelets increased.The blood sugar decreased as did the protein‐bound iodine. — No significant changes in serum potassium or sodium were found.At electrophoresis an increase of the albumin fraction was found, while β1‐,β2‐and γ‐globulins decreased.From the tissue studies — made on hibernating hedgehogs in late February to early March and on non‐hibernating ones in September — it can be seen that the magnesium content of the heart was lower during winter; the cytochrome c content, however, did not change.Sugar, aceton or aceto‐acetic acid were not found in the urine. Urinary albumin, however, appeared in all the hibernating animals and in half of the non‐hibernating ones.Part of this study was supported by a grant from the Medical Research Fund of the Swedish Life Insurance Companies. Our thanks are due to the head and personal of the Central Chemical Laboratory of Allmänna Sjukhuset and to Drs. BengtSkanseand S. E. Björkmanfor valuable

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01363.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.It is shown that the erythrocytes of ranae esculentae and temporariae behave very much as those from pigeons.The blood taken from the neck of the frogs shows a marked, and in some cases a very rapid absorption of potassium from the plasma. If the frogs are cooled (2°) for an hour before the bleeding the erythrocytes show no spontaneous absorption.Addition of hypertonic sodium chloride solution is followed by a potassium absorption of the red blood cells

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01364.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.When the frogs are placed in ice‐water for one hour and then bled, plasma potassium in most cases is increasing. Addition of adrenaline and noradrenaline make the blood cells absorb potassium.Adrenaline has an effect down to 0.01 μg/ml, noradrenaline is from 10 to 100 times less efficient.Hppertonic plasma plus adrenaline or noradrenaline produces extremely low potassium values (below 0.5 mM/1).When pigeon blood is rocked at 43° for one and a half hour the plasma concentration is rising. The pigeon blood cells are now very sensitive to adrenaline and noradrenaline (noradrenaline 2–3 times more efficient).Down to 0.001 μg/ml or perhaps even 0.0001 μg/ml of noradrenaline has an effect.It is of importance that all the samples are dealt with in exactly the same way (dilution. shaki

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01365.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.1. The effects on the cat's arterial blood pressure of histamine, β‐(2‐pyridyl)‐ethylamine and acetylcholine injected into the femoral vein, femoral artery and renal artery have been studied.2. As judged by the relative effectiveness of these injections the cat's kidney has a considerable capacity to remove injected histamine from the circulating blood.3. After the administration of histaminase inhibitors the depressor response to histamine injected into the renal artery was potentiated.4. Evidence is presented that this potentiation is due to the inhibition of the histaminase in the kidney.5. The maximum potentiation obtained in these experiments would correspond to an approximate reduction by 60 per cent of the kidney's capacity to remove injected histamine from the blood.6. No potentiation of the effect of histamine injected into the femoral artery or vein was observed.Valuable technical assistance was given by miss 81.‐B. Johansson. The investigation was supported by grants from the Medical Facul

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01366.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.Caseins from milks of homo, cow, goat, sheep, horse. reindeer and whale have been investigated for their content of hexose hexosamine and sialic acid.The total carbohydrate content does not exceed2 %except in the case of human casein, which contains about 4 %. The amount of all components investigated is greater in human casein, the difference in comparison with other species investigated being most pronounced for hexes and hexosamine.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01367.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.The repolarization of the end‐plate region and the neuromuscular block caused in frog skeletal muscle by persisting high concentrations of acetylcholine could be due either to a niechanisni rrducing the reactivity of the end‐plate “receptors” without affecting the membrane.i. e.a tubocurarine‐like effect. or to the possibility that the membrane at the end‐plate region was left highly permeable to ions other than sodium.To determine which of these two alternative iriechanisms is lrsponsible for the effects of persisting concentrations of acctylcholine, determinations were made of the transverse electric. membrane resistance at the end‐plate region heforc and after the application of acetylcholine.It was shown that the transverse membrane resistance was completely normal when acetylcholine had caused a neuromuscular block and the end‐plate region was repolarized.This excludes the possibility that the repolarization of the end‐plate region with the neuromuscular block in the presence of persisting concentrations of acetylcholine is due to an increase in the ionic permeability of the muscle membrane. It is concluded that the only other known mode of action which could account for these effects of acetylcholine is that exerte

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01368.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.The action of pentobarbital sodium on neuromuscular transmission and the effects of pentobarbital, urethan, chloral hydrate, chloralose, paraldehyde and tribromethanol on skeletal muscle excitability has been investigated with the intracellular micro‐electrode technique in the isolated sartorius nerve‐muscle preparation of the frog.Pentobarbital sodium blocked neuromuscular transmission by rendering the end‐plate “receptors” unreactive to the depolarizing effect of acetylcholine.All agents caused an increase in the electric “threshold” of the muscle membrane and reduced or abolished the action potential. The rate of rise of an action potential was decreased by all agents.These effects occurred without significant changes in the resting membrane potential of the muscle fibre and without a decrease in the transverse electric resistance of the muscle membrane.On the basis of the ionic hypothesis for electric activity in nerve and muscle (Hodgkinand Katz1949). it is suggested that these effects on the membrane “threshold” and on the action potential are due to a reduction of the selective sodium conductance change caused by an inactivation of the “sodium carrying mechanism” in the muscle membrane.A close relationship was observed between the hypnotic dose in the intact frog and the concentration of the respective agent that caused a reduction of the selective sodium conductance change in the frog ske

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01369.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.The reaction of the mast cells to histamine, the chemical histamine‐liberators compound 48/80 and stilbamidine, peptone and water was studied inlivingconnective tissue of the hamster cheek pouch. Degradation of the cells was invariably observed and occasionally irreversible disruption. The degranulation is interpreted as a response to increased tissue fluid, which in turn may be due to increased capillary permeability. The mucopoly‐saccharide‐containing granular substance of the mast cells may bind extracellular water and thus maintain the gel structure of the connective‐tissue ground substance. This view unites the results of previous experiments on the relation of the mast cells to histamine as well as to tissue mucopolysacc

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01370.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.Feeding of cholesterol at a dietary level of 1 % together with 10 or 20 % peanut oil to chicks caused a decrease in the amount of tetraenoic acid in the liver. especially when expressed as per cent of total fatty acids.When the diet did not contain fat. 1 % cholesterol had no influence on the amount of liver tetraenoic acid.Liver pentaenoic acid and hexaenoic acids. the amounts of which were low under the conditions of the experiment. seemed to be influenced in the same direction as tetraenoic.No significant change in liver dienoic or trienoic acids expressed as per cent of total fatty acids was found as a consequence of feeding 1 % cholesterol. When expressed as mg per g liver or per whole liver dienoic increased when 1 % cholesterol was fed with 10 or 20 % peanut oil.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01371.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY

摘要:

Summary.In cats stimulation of the accelerans nerves exerts a much stronger effect on the heart rate than the hormones released at a similar activation of the adrenal medullas. This is in accordance with the characteristics of the sympatho‐adrenal control of other autonomic effectors.The heart response is sometimes seen to vanish quite rapidly on interruption of a low‐frequency accelerans nerve stimulation. It is therefore discussed whether the prompt reflex decreases of stroke volume, known to occur on baroceptor stimulation in man, really necessitate the assumption of a direct vagal control of the heart ventricles. It is after all not impossible that this is the consequence of an inhibition of a tonic sympathetic influence on the heart and adjacent capacity vessels, factors which both must result in some decrease of stroke vol

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1956.tb01372.x

出版商:Blackwell Publishing Ltd    

年代:1956

数据来源: WILEY