bluuebunny/crossref_metadata_2025 huggingface dataset:
A Further Analysis of the Neuromuscular Block Caused by dcetylcholine
Authors: THESLEFF BY STEPHEN
Published: December 2008

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 exerted hp tubocurarine.
The Effect of Anesthetic Agents on Skeletal Muscle Membrane
Authors: THESLEFF STEPHEN
Published: December 2008

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 (Hodgkin and Katz 1949). 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 skeletal muscle membrane.
Transcapillary Migrntion of Ethyl Alcohol in the Pulmonary Circulstion. A Method for Determining the Water Content of the Lungs in Vivo
Authors: ANTHONISEN POUL , CRONE CHRISTIAN
Published: December 2008

A method is described for determining the extravascular water content of the lungs in living humans. The method is based on a determination of the amount of ethylalcohol lost from the capillary bed during the first circulation through the lungs. When the alcohol concentration of the extravascular water was also known, the space of distribution of alcohol could be calculated. There is reason to believe that the extravasculax alcohol space represents the total extravascular water content of the lungs.

In 15 normal subjects the method showed a mean value of 515 ± 27 ml (S. E., n =15). Three experiments performed on the same subject showed a maximum deviation from the mean value of ± 10 per cent.

The present investigation indicates that the total weight of the extravascular lung tissue is about 600 grams, and consequently the amount of blood in the capillaries and minor vessels of the lungs which is not lost at removal must be 300–400 ml.
Functional Organization of the Dorsal Spino‐Cerebellar Tract in the Cat.: V. Further Experiments on Convergence of Excitatory and Inhibitory Actions.
Authors: HOLMQVIST B. , LUNDBERG A. , OSCARSSON O.
Published: December 2008

Intra‐axonal recording in Flechsig's fasciculus was used for a further investigation of the functional organization of the dorsal spino‐cerebellar tract.

After ipsilateral section of lumbar and sacral dorsal roots, many neurons identified as belonging to the dorsal spino‐cerebellar tract (neurons activated by group I muscle afferents) were found to have a resting discharge. In silent neurons a discharge could be made to appear after repetitive stimulation of dorsal roots. It is concluded that these neurons receive excitatory action from interneurons.

Convergence of excitation and inhibition onto DSCT neurons from various muscles was studied with the use of electrical stimulation of muscle nerves as well as with adequate activation of stretch receptors.

As evidenced by monosynaptic excitation on single shock stimulation of muscle nerves, convergence of excitatory action mediated by group I afferents was found to be rather limited. A number of neurons can only be fired from one muscle nerve but some from as many as three out of seven nerves (including non‐synergists).

Convergence of inhibitory action mediated by group I afferents is extensive also from other muscles than the antagonist of the nerve supplying the main excitatory action.
The Excretion of Bile Acids in Kats Treated with Chemotherapeutics.1
Authors: LINDSTEDT SVEN , NORMAN ARNE
Published: December 2008

Summary. Cholic acid‐24‐14C has been administered to rats treated with intestinal chemotherapeutics and the rate of elimination has been followed. In rats given phtalylsulfathiazolum and terramycin a much slower rate of excretion was observed than in normal rats. The half‐lifetime of the bile acid molecule was estimated to be 10–15 days.
Histamine Liberation Produced in the Perfuse Paw of the Cat by 48/80 and Extracts from Jellyfish (Cyanea Capillata) and Eelworm (Ascaris Lumbricoides) from Swine.
Authors: HÖGBERG BERTIL , THUFVESSON GUNNAR , UVNÄS BÖRJE
Published: December 2008

Summary. A technique. is described for the use of thc perfused paw of the cat as a test object for assaying the activity of histamine liberating agents.
The Intestinal Absorption and Metabolism of Chimyl Alcohol in the Rat.
Authors: BERGSTRÖM SUNE , BLOMSTRAND ROLF
Published: December 2008

Summary. Unanaesthetized rats provided with a thoracic duct fistula were fed [14C]‐labeled chimyl alcohol (α‐[1‐14C]‐hexadecylglyceryl ether) dissolved in olive oil.

The labelled chimyl alcohol was absorbed to 95 per cent. The remainder was recovered in the unsaponifiable fraction of fecal lipids. About 50 per cent of the absorbed activity was recovered in the lymph lipids.

In the lymph lipids about half of the radioactivity was associated with palmitic acid, indicating a splitting of the ether bond of the chimyl alcohol and subsequently oxidation of the cetyl alcohol moiety to palmitic acid in the mucosa cells. The palmitic acid was incorporated into the lymph triglycerides and phospholipids in the usual way.

The other half of the activity in the lymph was present as chimyl alcohol about half of which was present as free chimyl alcohol. The remainder of the chimyl alcohol had been esterified during the absorption process and behaved chromatographically as a triglyceride that yielded chimyl alcohol after alkaline saponification.

Chimyl alcohol is thus well absorbed but extensively metabolized already during the absorption process.
Mechanism of the Relaxing Effect of: Adrenaline on Bovine Coronary Vessels
Authors: MOHME‐LUNDHOLM ELLA
Published: December 2008

The effect of adrenaline, noradrenaline and lactic acid was investigated on isolated coronary vessels from cow.

All these substances had a relaxing effect, coincident with an increase in the lactic acid content of the smooth muscle. The respective effects produced by adrenaline and noradrenaline were of similar magnitude to those induced by addition of lactic acid.

Cu++ions totally inhibited the relaxing and lactic‐acid‐producing effects of adrenaline and noradrenaline on coronary vessels. The former effect was also completely abolished by other glycolysis inhibiting substances such as monoiodoacetic acid, sodium fluoride, dl‐glyceraldehyde, sodium azide, sodium arsenate and Ca+. ions, as well as by an increase in the alkalinity of the nutrient solution.

The effect of other spasmolytics, such as theophylline, was not inhibited by glycolysis inhibiting substances or alkalization of the nutrient solution.

These results suggest that the relaxing effect of adrenaline and noradrenaline on isolated blood vessels is due to their ability to stimulate the lactic acid production in the muscle layer.
The Inhibitory Action of a Compound Obtained from Hip Seeds (HSC) on the Release of Histamine and the Disruption of Nast Cells Produced by Compound 48/80 and Extracts from Jellyfish (Cyanea Capillata) and Eelworm of Swine (Ascaris Lumbricoides)
Authors: HÖGBERG BERTIL , SÜDOW GÖRAN , THON INGA‐LISA , UVNÄS BORJE
Published: December 2008

Hip seed extracts prepared by repeated precipitation with alcohol or trirhloracetic acid extraction and barium fractionation were observed to block:

(1)The histamine liberation produced in perfused cat's paw by 48/80 and by extracts from jellyfish (Cyanea capillata) and the eelworm of swine (Ascaris lumbricoides).

(2) The rupture of mast cells produced by the same three agents.
Increase in Noradrenaline Excretion Following Activation of the Vasomotor System during Tilting in Adrenalectomized Patients
Authors: von EULER U. S. , FRANKSSON C.
Published: December 2008

The noradrenaline excretion figures in adrenalectomized patients were significantly increased during tilting head‐up + 750 as compared with the figures during recumbency, indicating that reflex activation of the vasomotor system causes an overflow of neurotransmitter into the circulating blood from where it can be partly recovered in the urine.
Histamine Degradation in Tissue Extracts from the Cat
Authors: LINDAHL KERSTIN M. , LINDELL S.‐E. , WESTLING H. , WHITE T.
Published: December 2008

1. The degradation of added histamine by crude extracts of kidney and small intestinal mucosa from adult cats was studied by measuring the oxygen consumption manometrically and by observing the loss of biological activity.

2. It was found that these extracts contained a histamine degradating enzyme with the characteristics of diamine oxidase.

3. No conclusive evidence was found in these experiments for the action of a histamine inactivating enzyme other than diamine oxidase.
Effects of Certain Biologically Occurring Substances on the Isolated Intestine of Fish
Authors: Von EULER U. S. , ÖSTLUND E.
Published: December 2008

5‐Hydroxytryptamine strongly stimulated intestinal motility in Pleuronectes and Labrus. It was less active in Anguilla, Lophius, Squalus and Raja, and had little or no action in Myxine.

Acetylcholine stimulated the isolated intestine in all species tested, although this effect was small in Squalus.

Histamine contracted the intestine in Pleuronectes, Labrus and Gadus but had either a small or no action in Lophius, Anguilla, Raja and Myzine.

Noradrenaline had only 1/30–1/100 of the inhibitory action of adrenaline on the intestine of Anguilla and Lophius. and 1/30 of the stimulating action of adrenaline on the intestine of Squalus.

Substance P stimulated the intestine of all species tested.
The Effect of Vagotomy on Gastric Motor Responses to Drugs in Dogs
Authors: MUREN A.
Published: December 2008

In gastric fistula dogs the gastric motor responses to carbachol, mecholyl and adrenaline were recorded under nembutal anaesthesia in repeated experiments before and after transthoracic vagotomy. Observations were made up to 200 days after operation.

The threshold doses of the drugs mentioned for motor responses were markedly lowered by vagotomy and the responses to graded doses showed a corresponding increase as compared with preoperative responses.

Increased sensitivity was usually apparent within the first 24 hours after vagotomy and maximal values were in most cases attained within the first 20 days. Later on, a decline in supersensitivity was observed, but preoperative values were not reached within 200 days after vagotomy. With carbachol and mecholyl the decline was pronounced; with adrenaline it was very slight.

Similar experiments were performed on conscious dogs, using carbachol and pilocarpine. The results for carbachol agreed closely with those obtained in experiments performed under nembutal. The threshold dose of pilocarpine was found to be considerably reduced after vagotomy.
The Incorporation of Labelled Phosphate into Different Compounds in the Rat Kidney. The Effect of Parathyroid Extract on an in vivo System.
Authors: DE VERDIER CARL‐HENRIC
Published: December 2008

The incorporation of P32 into nucleotides, phosphoproteins and RNA from rat kidney has been investigated in normal and parathyroidectomized animals and the effect of parathyroid extract has been studied. The rats were killed 1.5 hours after the hormone injection and 1 hour after the parenteral administration of radioactive phosphate. The renal nucleotide pattern is characterized by a relatively high concentration of a substance which is most likely uridine diphosphate or a derivative of it. The parathyroid hormone seems to specially stimulate the incorporation of radiophosphate into this compound and into the phosphoproteins.
Effects of Compound 48/80 on Blood Pressure and Plasma Histamine Level of Normal Dogs and Dogs with Mastocytoma.1
Authors: LARSSON BENGT
Published: December 2008

Six healthy dogs and ten dogs with mastocytoma were studied. Of the latter, seven were treated with compound 48/80 intravenously. The blood pressure, plasma histamine and/or histamine content of the tumour was studied, and the results discussed in relation to the pertinent literature.
Catheterization of the Renal Arteries in Dogs and Cats
Authors: LINDELL S. E. , OLIN T.
Published: December 2008

A technique of catheterization of the renal arteries from a femoral artery in dogs and cats is described.

The catheter did not influence the renal blood flow as measured on the venous side.

The insertion of the catheter was not followed by any changes in the clearance of phenol red as measured for each kidney separately.

We are greatly indebted to Miss Karen Nilsson for help with the photometry and to Mr. Olle Jönsson, who prepared the gold tubes.
Multielectrode Study of the Territory of a Motor Unit
Authors: BUCHTHAL FRITZ , GULD CHRISTIAN , ROSENFALCK POUL
Published: December 2008

By means of multielectrodes containing twelve leads along a 25 mm distance (Fig. 1) the spread of action potentials from a motor unit was studied over a cross section of the brachial biceps in man. The territory of the motor unit could be determined from the analysis of a single cross section of the muscle, since its fibres pass uninterrupted from tendon to tendon.

The mutual position of two multielectrodes inserted perpendicularly to each other into the muscle was determined with an accuracy of 0.2 mm by recording with one multielectrode subthreshold pulses sent through successive leads of the other multielectrode (Fig. 2).

The action potentials of a motor unit spread over an approximately circular area as evidenced by experiments in which the two multielectrodes traversed the centre of the motor unit (Fig. 4) and other experiments in which one of the multielectrodes was situated at the periphery of the motor unit (Fig. 5).

Potentials with spike components exceeding 50 μV were confined to an average area four to six mm in diameter (Fig. 6 A). These potentials had a protracted terminal component of low amplitude and if they were recorded outside the site of innervation an initial positive component as well. Outside the area in which spike potentials occurred the potentials had a low amplitude, a short duration and a negative sign (Figs. 3, 4, 5).

On account of volume conduction the action potentials were picked up in a larger area than occupied by the fibres of the motor unit. By means of the relationship between spike amplitude and distance from the potential source (Fig. 1 C) the average territory of the motor unit was determined to be four to six mm (minimum two and maximum ten mm) (Fig. 6 B). This area allows space for the fibres of ten overlapping motor units.

On the same lead of the multielectrode action potentials from maximally six different motor units were recorded. Their potentials were often similar in shape so that they could be identified only by their discharge frequency (Fig. 9). The muscle fibres of as many as three of the intermingling motor units overlapped entirely (Fig. 8). The temporal dispersion of the spikes recorded on the different leads of the multielectrode was identical for these overlapping motor units (Fig. 7).

The results are discussed with respect to their bearing on the parameters of the motor unit potential: The action potential of the motor unit arises from the summation of temporally dispersed potentials originating from fibre groups at a mutual distance of 0.3 to 1 mm. The amplitude of the motor unit potential is largely determined by the distance of the recording electrode from the fibre group closest to the electrode. The shape of the potential derives from the way in which the action potentials of two to three of these fibre groups summate. The duration of the potential is determined by the temporal dispersion of the component potentials due to the spatial dispersion of the end plates in the innervation zone.
Influence of Added Dead Space on Pulmonary Ventilation.
Authors: BOUHUYS AREND , JÖNSSON RAGNAR , LUNDIN GUNNAR
Published: December 2008

Hyperventilation due to extra dead space did not cause any significant improvement in ventilatory efficiency as measured in nitrogen wash‐out experiments during oxygen breathing. In the experiments with extra dead space a significant increase in degree of uniformity of ventilation could be demonstrated. The subject's dead space increased, and the over‐all efficiency remained constant. The efficiency‐improving effect of a better distribution and the efficiency‐deteriorating effect of a larger dead space probably cancelled out. The better distribution is most probably explained by the effect of mixing of gas from different lung fractions in the large dead space. The experiments were performed with a nitrogen meter.
Carbon Monoxide Uptake in Man During Rest and Work.
Authors: BOSÆUS ELISABETH , FRIBERG LARS
Published: December 2008

Ten resting subjects (5 nonsmokers and 5 smokers) were exposed to 0.010, 0.023, 0.040 and 0.080 vol. per cent CO. The work studies were made on 5 nonsmokers. They breathed 0.023 and 0.040 vol. per cent CO at rest and during work (bicycle ergometer) corresponding to 300, 600 and 900 kgm per minute.
Influence of the Vagal Innervation on Gastric Motor Responses to Adrenaline and Noradrenaline.
Authors: MUREN A.
Published: December 2008

A large number of serial experiments on dogs have shown that the inhibitory effect of adrenaline and noradrenaline on gastric motility observed in conscious dogs is reversed to an augmentory one by different procedures which interfere with the normal vagal influence such as anaesthesia, vagotomy and treatment with atropine‐like substances.

Acute experiments have shown that the augmentory responses obtained during anaesthesia are reversed to inhibitory ones when gastric motor activity is elicited by stimulation of the vagus in the neck. On the other hand, if gastric motor activity is induced by carbachol, the augmentory responses are not regularly reversed.

The investigation was supported by a grant from the Medical Faculty in Lund.

Technical assistance was given by Miss Asta Hector.
Studies on the Placental Transfer of Phosphate in the Guinea Pig:III. Phosphorus Compounds in the Placenta and their Uptake of Radioactive Phosphorus.1
Authors: FUCHS FRITZ , FUCHS ANNA‐RIITTA
Published: December 2008

Determinations of the various phosphorus fractious in the guinea pig placenta in a series of experiments on the placental transfer of phosphate have shown that the orthophosphate concentration is very high in the placental tissue as compared with the maternal and foetal plasma. The concentration increases slowly from the 29th to the 59th day of gestation and may decrease thereafter.

Thirty minutes after intravenous injection of radioactive phosphate into the mother the orthophosphate in the placenta has reached a specific activity of one third of that of the inorganic phosphate in the maternal plasma. It has the highest specific activity of the placental phosphorus fractions.

Adenosine diphosphate and triphosphate are found in approximately the same concentrations as in the uterine muscle during pregnancy in the rat, the rabbit and the human. The labile phosphorus of these compounds is in equilibrium with the orthophosphate with regard to radioactive phosphorus.

Glucose‐1‐phosphate is present in a low concentration, but it acquires a high relative specific activity. More glucose‐6‐phosphate is present, but with a low relative specific activity.

The inorganic phosphate in the foetal plasma obtains in thirty minutes a specific activity of about half that of the placental orthophosphate.
Action Potentials Recorded Intra‐ and Extra‐ cellularly from the Isolated Frog Muscle Fibre in Ringer's Solution and in Air
Authors: HÅKANSSON C. H.
Published: December 2008

Action potentials were recorded inside and outside isolated frog muscle fibres in Ringer's solution and in moist air in order to correlate the different potentials and to study volume conduction

The extracellular action potential recorded from isolated frog muscle fibres in Ringer's solution was diphasic with a first positive and a second negative phase.

The duration of the potential measured at a distance of 30 μ from the surface of the fibre was 2.67 ± 0.14 msec (21.2° C). It increased slightly with increasing fibre circumference from 2.5 msec in a fibre of 150 μ circumference to 3.2 msec in a fibre of 350 μ, circumference.

The amplitude increased proportionally to the square of the fibre circumference. The peak to peak amplitude was 0.8 to 2.9 m V 30 μ from the surface of the fibre. Near the fibre the amplitude decreased linearly with the logarithm of the distance from the axis of the fibre. At distances (d) exceeding 0.15 mm from the axis of the fibre the amplitude decreased as d‐1,3.

The peak of the intracellularly measured potential coincided with the negative peak of the extracellular potential with the fibre in Ringer's solution. This indicates that the extracellular action potential can be accounted for by means of the second derivative of the intracellular potential. A third positive phase of the volume conducted potential which is present in nerve disappears within the noise level for the muscle fibre in Ringer's solution because of the more protracted course of repolarization.

The spread of the action potential along the fibre determined from the intracellularly recorded action potential was 8.8 ±0.9 mm (conduction velocity × duration of the potential from 50 per cent rise to 50 per cent fall).

From the action potentials recorded at different distances from the fibre equipotential lines of the travelling potential field were constructed. By means of this field the charge passing the membrane during depolarization was determined to 1.4× 10‐6 coulomb per cm2.

The surface action potential from a fibre surrounded by a moist gas mixture had an amplitude of the same order of magnitude as the intracellularly measured action potential with the fibre surrounded by Ringer's solution. The time for rise from 20 to 100 per cent of crest was about half the rise time of the intracellularly recorded potential. The duration of the reconstructed monophasic potential from 50 per cent rise to 50 per cent full was slightly shorter than the intracellular action potential.

The conduction velocity of the potential with the fibre in air was half that measured in Ringer's solution (2.41 ± 0.12 m per sec in Ringer's solution; 1.05 ± 0.05 m per sec in air at 21° C). From this difference in propagation velocity the impedance of the Ringer's film surrounding the fibre in air was estimated to 12 megohms per cm. The thickness of the Ringer's layer was about two μ.
The Influence of Adrenaline, Nor‐adrenaline, and Acetylcholine on the Electrocardiogram of the Isolated Perfused Guinea‐pig Heart
Authors: JOHANSSON BENGT , VENDSALU AADO
Published: December 2008

The effect of increasingly large doses of adrenaline, nor‐adrenaline, and acetylcholine on the electrocardiogram of the isolated, perfused guinea‐pig heart was studied before and after administration of dibenamine and atropine, respectively.

 The threshold value for nor‐adrenaline to cause electrocardiographic changes was lower than that for adrenaline. The chronotropic effect seemed to be the same for the two substances at low doses, while at higher doses nor‐adrenaline seemed to be the more effective positive chronotropic agent. Cardiac arrhythmias were observed in about one‐third of the experiments and nor‐adrenaline appeared to be as potent as adrenaline in developing conduction disturbances and evoking ectopic discharges. Adrenaline increased the amplitude of the P wave, while nor‐adrenaline had no effect on the amplitude. There was no difference between the two substances as to the changes in the P—R interval, Q—T duration, S—T segment, or on the T waves. At lower doses the P—R interval was shortened; a prolongation was seen at high doses. The Q—T duration was first prolonged, but 30 to 60 secs later a shortening appeared. The T waves showed reduction in amplitude, so that a previously positive or negative T wave became less positive or less negative, respectively. In some hearts the opposite results were seen. At high doses a previously positive T wave could become negative and vice versa.

  After dibenaminization, slightly higher threshold values of adrenaline and nor‐adrenaline were necessary in order to produce electrocardiographic changes. At higher doses of the two substances, dibenamine could not abolish or decrease the chronotropic effect or electrocardiographic contour changes.

  At lower doses acetylcholine produced decreased auricular rate, with increasing doses heart block occurred, partial or complete. A propensity to evoke auricular fibrillation was evident. Ectopic auricular or ventricular discharges occurred. The P wave often became notched, its amplitude and duration decreased. In some experiments the Q—T duration was shortened and was followed by a lengthening. The T wave amplitude increased so that a previously positive or negative T wave became more positive or more negative, respectively.

 The inhibitory effect of acetylcholine was abolished by atropine. High doses of acetylcholine caused acceleration of the heart rate in atropinized hearts.
Enzymic Oxidation of Some Substances Related to Histamine
Authors: LINDELL S.‐E. , WESTLING H.
Published: December 2008

The action of histaminase and amine oxidase preparations on seven histamine‐like substances was examined. The enzyme preparations were obtained from pig and cat kidney and from guinea‐pig and rabbit liver.

 Some of the substances studied were found to be oxidized by amine oxidase preparations but not by histaminase.

 1‐methyl‐4βaminoethyl imidazole was found to be a good substrate of histaminase. It was also oxidized by amine oxidase preparations
The Mechanism of Establishment of Secretory Potentials in Sublingual tiland Cells.
Authors: LUNDBERG ANDERS
Published: December 2008

An attempt has been made to analyse the mechanism of establishment of the secretory potential over the outer gland cell membrane in the sublingual gland of the cat, as well as its importance for the secretion of salt and water.

Double‐barrelled microelectrodes were inserted into gland cells permitting recording of the intracellular potential with current flow through one channel to change the membrane potential. The secretory potential over the outer membrane could still be evoked when the membrane potential had been raised to more than 100 mV. It is concluded that this secretory potential is due to an active transport of ions over the outer membrane and assumed to be an inward transport of anions.

The resistance between the cell interior and the external medium measured with this technique was about 2 Mω in the resting state and 1.8 Mω during activation. Measurement has also been made of the resistance between the external medium and the lumen of the gland cell tubule and of the ratio of the resistances offered by the inner and outer gland cell membranes to a current passed between the external medium and the lumen. On the basis of these measurements and the assumption that the gland cell tubule can be considered as a core conductor the specific resistances of the outer and inner gland cell membrane were derived to 18 respectively 11 ohm cm2 in the resting cell. With activation there was no significant change in the resistance of the inner cell membrane, whereas the resistance of the outer membrane decreased by about 50 per cent.

The anionic content of the saliva secreted by a number of gland cells with a certain area of outer membrane has been compared with the amount of current needed from an external battery to equal the secretory potential over this area of outer gland cell membrane. The probable order of magnitude of the active anionic transport is discussed in view of these findings.

The hypothesis is forwarded that secretion of salt and water largely is caused by active transport of anions (mainly or exclusively chloride) over the outer gland cell membrane.
Effect of Tributyrin on Circulation and Respiration.
Authors: WRETLIND ARVID
Published: December 2008

The effects of tributyrin on circulation and respiration have been studied by injection of a tributyrin emulsion.

On intravenous injection, the effect of tributyrin on circulation is characterized by rapidly appearing bradycardia and a fall in blood pressure, followed by a rise in blood pressure.

Bradycardia and the fall in blood pressure are inhibited by vagotomy and procaine. They do not appear with injection into the left ventricle, aorta or large arteries. The effect is probably‐elicited through receptors with afferent pathways in the vagus, and located to the right side of the heart or the lungs. The rise in blood pressure is largely due to contraction of peripheral blood vessels. This rise is not inhibited by tetraethylammonium, hexamethonium, dihydroergotamine, ergotamine or procaine.

In the heart‐lung preparation, tributyrin decreases the heart action. The blood flow in the abdominal aorta is reduced, together with a rise in blood pressure after injection of tributyrin.

The effect on respiration is characterized by apnoea with a rapid onset, followed by hyperpnoea. Apnoea is not elicited after vagotomy, but appears after administration of atropine or procaine. Injection into the left ventricle, aorta or large arteries does not produce apnoea. Apnoea is probably evoked via receptors in the right side of the heart or the lungs. The hyperpnoea is considered to be produced by central stimulation.

Bradycardia, the fall in blood pressure and apnoea associated with injection of tributyrin seem to be elicited in the same way as the Bezold‐Jarisch reflex described earlier.

Tributyrin is found to have neither an inhibitory nor a stimulating effect on the superior cervical ganglion.

The LD50 of tributyrin on intravenous injection into mice is 320 ± 11 mg/kg.
Eine oximetrische Methode zur Kreislaufzeitmessung am menschlichen Gehirn.
Authors: NILSSON NILS JOHAN
Published: December 2008

Eilie Methode zur Messung der Kreislaufzeit durcb das menschliche Gehirn unter Verwendung von zwei Oximetereinheiten wird besehrieben.

Die Sauerstoffsättigung des arterialisierten Ohrblutes und die des venösen Blutes im Bulbus jugularis werden gleichzeitig registriert mit Hilfe einer Ohreinheit bzw. einer Cuvetteneinheit, die auf der Punktionskanüle des Bulbus jugularis montiert ist. Das Jugularisblut wird von einer Rekordspritze mit Synchronmotorantrieb gleichmässig durch die Einheit gesogeu.

Durch kurzdauerndes Stickstoffatmen werden rasche Änderungen der Sättigung des Blutes hervorgerufen. Die kürzeste Kreislaufzeit wird als Abstand zwischen korrespondierenden Punkten der Arterien‐ und Venenkurve gemessen.

Nach Injektionen von NaCl oder Evans blue in die A. carotis communis wurden Befunde erhoben, die darauf deuten, dass die Gehirndurchblutung unmittelbar naeh einer intraarteriellen Injektion vorübergehend zunimmt.
Der Off‐Effekt im menschlichen Elektroretinogramm.
Authors: HECK J.
Published: December 2008

Nach Helladaptation findet man im menschlichen ERG bei intermittierender Belichtung neben einer komplexen On‐Antwort, die dem Einzelreiz‐ERG von congenital Nachtblinden entspricht, einen doppelten positiven Off‐Effekt. “On” und “Off” weisen spiegelbildliches Verhalten auf. Die Abhangigkeit des Off‐Effektes vom Adaptationszustand und von der Lichtintensität wird untersucht, und das Zustandekommen seiner doppelten Konfiguration diskutiert.
The Respiratory Gaseous Exchange After a Short Burst of Exercise.
Authors: ERIKSON. H.
Published: December 2008

Spirometric investigations of the respiratory gaseous exchange during resting, not basal, conditions and the recovery after a 70 yard sprint are reported.

It is shown that around 10 minutes after connection with the spirometer fairly constant values for oxygen uptake and carbon dioxide output were obtained. These resting values were regained shortly after the exercise. The time used for elimination of excess carbon dioxide was longer and more constant, and showed greater interindividual differences than the time required for covering the oxygen debt.

Well trained subjects with good results in track competitions showed the shortest recovery times. Trained subjects with fair to poor results had recovery times overlapping the recovery times of untrained subjects in good physical condition.
Lactic Acid Content in Human Venous Blood During Hypoxia at High Altitude.
Authors: HARBOE M.
Published: December 2008

The concentration of lactic acid in human venous blood has been determined during hypoxia — the subjects breathing atmospheric air at high altitudes. Lactic acid concentration increases, depending on the degree and duration of hypoxia.

Apart from heights of 15,000 to approximately 20,000 feet, where the lactic acid concentration increases simultaneously with increasing disability, such concentration is poorly correlated to the functional disability during hypoxia.
The Effect of Atropine on the Acidity of a Denervated Gastric Pouch.
Authors: NORDGREN BENGT , ÖBRINK KARL JOHAN
Published: December 2008

In experiments in pouch dogs it was shown that after administration of atropine the volume secretion rate declines much sooner than the acidity. The time lag was mainly due to the remaining volume in the gastric pouch (The ‘lake hypothesis’ of Öbrink1948). Earlier observations of other authors that atropine could cause an increased acidity were, however, confirmed especially in cats where HC1 was instilled and a permeability coefficient for the hydrogen ions calculated. Atropine caused a slower decrease in acidity, which could be explained by a decreased permeability for the hydrogen ions. (The diffusion theory of Teorell1933, 1947.) The action of atropine on the acidity regulation was thought to depend on its effect on the vascularisation of the gastric mucosa.
The Available Glycogen in Man and the Connection between Rate of Oxygen Intake and Carbohydrate Usage.
Authors: HEDMAN RUNE
Published: December 2008

The type of work was ski running at a constant speed on a 750 m circular track set up on level ground. Four well trained male subjects performed this work to the point of exhaustion. During 150–160 min three of the subjects were able to run at a work intensity which corresponded to an oxygen intake of 3.6‐4.1 l/min. (The oxygen intake for the fourth subject was 3.4‐3.9 l/min during 120 min.) The total energy expenditure during this time was 2,000–3,000 Cal; the pulmonary ventilation rose to a mean of 90 l/min and the heart rate was 160–190 beats/min. By determination of the respiratory metabolism the quantity of oxidized carbohydrates was calculated.

The RQ values remained during the whole run at a practically constant level. One subject, who had reduced his glycogen depot by 445 g, continued to get 55 % of his calorie need from carbohydrates, although hypoglycemic symptoms were present.

The blood lactic acid concentrations at the end of these long periods of work were slightly increased (20 mg %).
A Modification of the Thiocholine Method for the Determination of Cholinesterase. I. Biochemical Evaluation of Selective Inhibitors.
Authors: HOLMSTEDT BO
Published: December 2008

Biochemical controls of the thiocholine method for the determination of cholinesterase have been performed both with partially purified enzyme and with enzymes from the cat.

The electrometric method that has been used for the determinations permits the use of the same pH and the presence of all the reagents used histochemically. The inhibition curves of aceto‐and butyrocholinesterase activity using DFP, Mipafox, BW 284c51, 302 IS and 306 IS have been determined. Of these inhibitors BW 284c51 and Mipafox were shown to be the most selective in the histochemical incubation solutions. The compounds were also tested against the crude enzymes from the cat, and showed equally good inhibitory properties.

The use of selective substrates and inhibitors is discussed. It is concluded that if biochemical controls of the thiocholine method are to be of value they must be made in exactly the same solution as used histochemically. The pH and the concentration of inhibitor in the solution must be based on controls run in vitro or erroneous localisation of the two types of cholinesterases may result.
The Mechanism of the Vasodilator Effect of Adrenaline. II. Influence of Anesthetics on the Depressor, Pressor and Lactic Acid Stimulating Effects of Adrenaline.
Authors: LUNDHOLM LENNART
Published: December 2008

The influence of different anesthetics on the depressor and pressor as well as the lactic acid stimulating effects of adrenaline were investigated in cats and compared with the corresponding effects in unanesthetized animals. Adrenaline was infused intravenously for 5 minutes in increasing doses ranging from 0.1 to 24.3 μg per kg body weight per minute.

In unanesthetized animals the depressor effect was very slight, although adrenaline reduced the total peripheral resistance; this probably because the blood‐pressure regulation was better than in the anesthetized animals. In most of the latter the depressor effect emerged, but its magnitude varied considerably according to the anesthetic employed. Broadly speaking, the depressor effect showed a statistically significant correlation both to adrenaline's ability to increase the lactic acid content of the blood and to the basal blood‐pressure level.

The same factors that amplified the depressor effect of adrenaline weakened its pressor effect. The latter was negatively correlated to the basal blood‐pressure level and to the lactic acid producing capacity of adrenaline. Further, the anesthetic had a direct inhibitory effect on adrenaline's vasoconstrictor action.

In the individual cases the influence of the different anesthetics on adrenaline's circulatory effect was explained as follows. Ether amplified the lactic acid production and raised the basal blood pressure in relation to adrenaline's effect on unanesthetized animals, the depressor effect was very pronounced and the pressor effect greatly weakened. Urethane did not influence the lactic acid production, but elevated the basal blood pressure; the depressor effect was distinct but the pressor effect weakened. Evipan did not demonstrably influence either the lactic acid production or the basal blood pressure; the depressor effect was somewhat greater and the pressor effect somewhat less than in unanesthetized animals. Dial inhibited the lactic acid production without definitely influencing the basal blood pressure; the depressor effect was weak but the pressor effect amplified. Chlo‐ralose inhibited the lactic acid producing action of adrenaline but concurrently raised the basal blood pressure; these effects on adrenaline's action tended to counterbalance each other.

Noradrenaline had neither a lactic acid stimulating nor a depressor effect on ether‐anesthetized cats.
Supersensitivity Caused by Denervation and by Cholinesterase Inhibitors.
Authors: STRÖMBLAD B. C. R.
Published: December 2008

Experiments on the cholinesterase activity of homogenates of normal and denervated salivary glands are described.

The percentage decrease after various types of denervations was the same as found earlier (Strömblad 1955 b) when the supernatant of the homogenate was estimated.

The changes in enzymic activity after denervations were compared with those found when mintakol (or TEPP) was injected into the glands via the secretory duct in amounts causing supersensitivity.

It was inferred that the supersensitivity found after denervations could not be wholly due to a decrease in cholinesterase activity. In case of preganglionic denervation it is doubtful if enzyme decrease could play any part in the supersensitivity, while in case of postganglionic parasympathetic denervation it was very suggestive. Experiments are also described which are in accord with a suggestion previously proposed that the difference in sensitivity between a pre‐and postganglionically denervated parotid gland is due to the greater fall in cholinesterase after postganglionic as compared with preganglionic denervation.

The supersensitivity caused by excision of the superior cervical ganglion could hardly be attributed to a decrease in cholinesterase activity of the gland.
The Albumin/Globulin Ratio in Plasma and Exudate of Chicks Suffering from Exudative Diathesis.
Authors: DAM HENRIK , HARTMANN S. , JACOBSEN JOHANNE E. , SØNDERGAARD EBBE
Published: December 2008

Tiselius‐electrophoresis was carried out on plasma from chicks on a normal commercial chicken ration, on a torula yeast containing artificial diet with or without vitamin E, and on exudate from chicks on the last mentioned diet.

The albumin/globulin ratios were found to be largely the same for plasma of chicks on the normal diet, on the diet with torula yeast supplemented with vitamin E, and for the exudate. Lower albumin/globulin ratios were found only for plasma of chicks having exudate.

The mobilities of the various plasma protein fractions were not influenced by the dietary regimen.

The protein fractions in the exudate had the same mobilities as the corresponding fractions in the plasmas.
Effects of Histaminase Inhibitors on the Blood Pressure Responses in Dogs to Histamine Injected into the Renal Artery.
Authors: LINDELL SVEN‐ERIC
Published: December 2008

1. The effects on the dog's blood pressure of histamine injected by vein or into the femoral or renal artery have been studied.

2. The effects of two histamine analogues, which were not oxidized by histaminase in vitro were also studied under the same conditions.

3. As judged from the relative effectiveness of histamine injected by these routes the kidney had a considerable capacity to remove injected histamine from the circulating blood.

4. Histaminase‐resistant histamine analogues were not removed as effectively as histamine by the kidney.

5. Histaminase inhibitors, such as aminoguanidine, B1‐pyrimidine and isonicotinylhydrazine potentiated the depressor responses to histamine given into the renal artery but not those to histamine given into the femoral artery or by vein.

6. The depressor responses to the histaminase‐resistant histamine analogues were not potentiated by the inhibitors.
Fibrinolytic Activity Derived from Guinea Pig Serum by Peptone.
Authors: OLESEN E. S.
Published: December 2008

1) Peptone, in combination with an isoelectric precipitation, releases fibrinolytic agents in normal guinea pig serum. These results confirm, with a different method, the finding of Ungar et al.

2) The formation of a plasminogen activator and an active protease is demonstrated.
The Elicitation of a Drinking Motor Conditioned Reaction by Electrical Stimulation of the Hypothalamic “Drinking Area” in the Goat.
Authors: ANDERSSON B. , WYRWICKA W.
Published: December 2008

When a drinking motor conditioned reaction was firmly established in goats it was possible to elicit the same reaction by electrical stimulation of the hypothalamic “drinking centre”.
Life Cycle of Granulocytes and Lymphocytes Determined by Making Use of 59Fe Labelled Haemin as a Tracer
Authors: RESEGOTTI LUIGU
Published: December 2008

In granulocytes and lymphocytes separated from the blood of the rabbit the incorporation of radioactive 59Fe into the haemin fraction was investigated.

Evidence is presented that the iron is incorporated into the haemins during the formation of these cells and remains in them during their life time. From the change of the specific activity of the haemin iron with time the average life span of both lymphocytes and granulocytes can thus be calculated.

The mean age of the granulocytes was found to be 8.8 days. It is presumably composed of two populations of about the same frequency but varying life time, one having a life span of 4.4, the other of 13.2 days. The mean age of 8.8 days is identical with the result obtained by Ottesen from 32P data of DNA isolated from granulocytes.

A very appreciable part of lymphocytes has a life span amounting to 145 days; 10 % only having one of 3 days. An almost identical result was arrived at by Ottesen in his DNA studies. A part of the lymphocytes entering the blood stream is still going on to incorporate haemin iron, thus to build up haemin.
Further Studies on the Intestinal Glucuronide Synthesis
Authors: HARTIALA K. J. V. , LEIKKOLA P. , SAVOLA. P.
Published: December 2008

Intragastric feeding of cinchophen in dog results in a significant increase in the portal blood glucuronide concentration in addition to the rise in hepatic and femoral blood glucuronide contents. Ligation of the common bile duct does not prevent the increase in portal blood glucuronide concentration.

These observations are taken as a further evidence to support our in vitro studies with tissue slices. These have shown that the mucous membrane of the gastrointestinal tract participates in the detoxication mechanisms and is capable to conjugate glucuronides with suitable substances present in the environment.
Blood Volume in Albino Rats Determined by the Plasma Dye Method
Authors: JØRGENSEN MOGENS , VOIGT JØRGEN , JENSEN ELSE M.
Published: December 2008

The average value of 31 determinations of circulating blood volume in adult albino rats by a simple plasma dye method using Evans' dye was found to be 5.92 ± 0.21 ml/100 g body weight with a variation from 3.68 ml/100 g to 8.24 ml/100 g.