bluuebunny/crossref_metadata_2025 huggingface dataset:
Lipoprotein Lipase Activity in Adipose Tissue from Hen, Chicken and Adult Human
Authors: Angervall Gunnar
Published: December 2008

Angervall, G. Lipoprotein lipase activity in adipose tissue from hen, chicken and adult human.

Lipoprotein lipase was extracted from acetone powder of hen and chicken adipose tissue with dilute ammonia. The enzyme was tested in vitro in a system with milk cream suspension as a substrate and pure albumin or inhibitor‐freed plasma as a fatty acid acceptor. The activity was measured as a decrease in optical density in the system and as a release of unesterified fatty acids per 10 mg of enzyme extract. Lipoprotein lipase activity was three or four times greater in extracts of chicken adipose tissue as compared with those of hen. In adult human adipose tissue, however, there was no or insignificant lipoprotein lipase activity in three of four cases. — The role of inhibitors of lipoprotein lipase in connection with the method was discussed.
Retention of Particles by the Reticulo‐Endothelial System
Authors: Juhlin Lennart
Published: December 2008

Juhlin, L. Retention of particles by the reticulo‐endothelial system.

Spherical particles of methyl methacrylate were injected intravenously in rabbits and mice. They are taken up by the R. E. S. primarily in the liver, spleen and bone marrow. The elimination from these organs was then studied, in some cases up to 18 months after injection. Three types of particles were used: Positively charged particles 0.05 μ in diameter and negatively charged particles 0.1 μ and 0.8 μ in diameter. These particles are all taken up by the R. E. S. and eliminated in a similar fashion. Approximately 50 per cent of the injected dose is eliminated from the body during the first month. In mice after 18 months about 10 per cent remained in the total body. Special polynuclear histiocytic cells were then found in the liver in which 0.8 μ particles could be seen with ordinary microscopy. The 0.8 μ particles increased in the spleen of rabbits and mice and in the bone marrow of rabbits during the first weeks. This seemed to be the result of a liberation of particles from the liver to the blood stream. The total amount of femur‐equivalent bone marrow in the rabbit skeleton was found to be 1.5 per cent of the body weight. The distribution of particles in different bones showed a bilateral symmetry, was not influenced by dose or particle size and was the same 3 hours and 20 days after injection.
Excitation, Inhibition and Rhythmical Activity in Hippocampal Pyramidal Cells in Rabbit
Authors: Euler Curt Von , Green J. D.
Published: December 2008

Euler, C. V. and J. D. Green. Excitation, inhibition and rhythmical activity in hippocampal pyramidal cells in rabbit.

The activity pattern of single hippocampal pyramidal cells has been studied in rabbit under light urethane anaesthesia and with encéphale isoléin response to various stimuli. Deep depolarization leading to initial excitation followed by in‐activation of spike generation has been found to be a commonly operating mechanism in the hippocampal pyramids. Such ‘inactivation processes’ have appeared spontaneously as well as in response to various stimuli. They may be driven with great precision as well as appearing rhythmically in after discharges. The ‘inactivation process’ was commonly followed by a hyper‐polarization. Thus two different mechanisms of inhibition followed each other. Prolonged septal stimulation provoked trains of rhythmically recurring inactivation processes with bursts of declining spikes at the rising phase of each depolarizing wave.

Close similarities between the theta rhythm and rhythmically recurring inactivation processes are described and it is suggested that the former is built up by the latter synchronously occurring in several neurones. The inactivation process was also found to be a commonly occurring cellular event during seizure activity.
Interhippocampal Impulses
Authors: Andersen Per
Published: December 2008

Andersen, P. Interhippocampal Impulses. III. Basal dendritic activation of CA3 neurorzs.

The commissural afferents of the hippocampal field CA3 terminate in the layer of the basal dendrites only (Blackstad 1956), making selective basal dendritic activation possible. The response of CA3 in response to a symmetrical contralateral stimulation is a diphasic spike followed by a negative wave, sometimes with a superimposed spike. The diphasic spike represents interhippocampal fibre activity. The negative wave was recorded only from the CA3 basal dendritic layer. It is partly an excitatory postsynaptic potential produced in the basal dendrites by the commissural volley, partly a postsynaptic CA3 neuron discharge. The spike is a more synchronous discharge of the same neurons. The commissural volley elicits spikes more seldom in CA3 than in CA1, where apical dendritic activation is the most prominent, suggesting that a cell discharge is easier produced by apical than by basal dendritic activation. The susceptibility to anoxia is similar for the two fields. Strychnine normally produces great changes in CA1 potentials, but has only minor influence on the CA3 commissural response.
Thalamic Neurones Responding to Tactile Stimulation of the Cat's Tongue
Authors: Landgren Sven
Published: December 2008

Landgren, S. Thalamic neurones responding to tactile stimulation of the cat's tongue.

Encéphale isolé preparations were used. Extracellular spike potentials were recorded from single neurones in Nucleus ventralis posteromedialis of the thalamus. – The response of 40 thalamic neurones to tactile, thermal and gustatory stimulation of the tongue and to electrical stimulation of the tongue and the ipsilateral dorsal ascending trigeminal tract was investigated. Out of these neurones 32 responded only to touch, 4 only to pressure, and 4 to both touch and cooling of the tongue. One third of the neurones showed tactile receptive fields about 2 mm in diameter. Two thirds had larger ipsilateral or contralateral receptive fields. No large bilateral fields of the type shown by cortical “touch cells” were observed. – The typical response evoked in thalamic neurones by touch or electrical stimulation of the tongue was a short burst of spikes. Generally no after‐discharge was seen, but repetitive tactile stimulation sometimes caused an increase in the spontaneous discharge. The mean latency of the first propagated spike in the response of a “touch cell” to electrical stimulation of the tongue was generally 3–6 msec (shortest latency 2.5 msec). Most mean latencies of response to tract stimulation were 1–2 msec (shortest latency 0.9 msec).
Thalamic Neurones Responding to Cooling of the Cat's Tongue
Authors: Landgren Sven
Published: December 2008

Abstract

Landqren, S. Thalamic neurones responding to cooling of the cat's tongue.

In encéphale isolé preparations extracellular spike potentials were recorded from single neurones in the thalamic nucleus ventralis posteromedialis (VPM). The effect on these neurones of thermal, mechanical, gustatory and electrical stimulation of the tongue and electrical stimulation of the ipsilateral dorsal ascending trigeminal tract was investigated.

Out of 62 neurones fully investigated 20 responded only to cooling of the tongue, 4 to touch or pressure and to cooling and 1 to warming.

The latency of the response of the “cold cells” was generally 6–14 msec to electrical stimulation of the tongue and 1.0–1.9 msec to stimulation of the tract.

The response of “cold cells” to constant temperatures applied to the tongue and to rapid changes between constant temperature levels was investigated. A drop in temperature caused an increased frequency of discharge, which adapted to a new constant level. In the range 40–20° C the larger the drop in temperature the higher was the initial as well as the maintained frequency. Warming the tongue to 37° C reduced the discharge. Above 45° C an increase was again observed.

The anatomical localization of the “cold cells” was laterally in. the medial parvocellular part of VPM.
Effects of RNA on Early Chick Embryos Cultivated in Vitro
Authors: Emanuelsson Hactar
Published: December 2008

The object of the present investigation has been to find out whether pure RNA can exert a stimulating action on the morphogenesis of early chick embryos. The experiments have been performed on 16 to 18‐hour‐old embryos cultivated in vitro. RNA from 1) area opaca of 2‐day‐old chick embryos 2) from heads of 6‐day‐old chick embryos and 3) from yolk‐sacs of 6‐day‐old chick embryos was tested. — After 24 hours' cultivation in vitro a marked growth and differentiation occurred in embryo‐regions homologous to those from which the RNA had been isolated. Other regions, however, were rather retarded in their development and displayed disturbed mitoses. Mitotic counts demonstrated an increased mitotic activity in the growth‐stimulated embryo‐regions. In the latter a slight increase in the percentage of anaphases + telophases also was noted. — Thus it appears that the pure RNA in itself has the capacity of stimulating growth and differentiation in chick embryos, the localization of the effect being dependent, however, on the origin of the RNA used.
Quantitative Studies on the Anaphylactic Mast‐Cell Reaction In Vivo in the Guinea Pig
Authors: Boréus Lars Olof
Published: December 2008

The anaphylactic reaction of tissue mast cells was studied quantitatively in vivo in the nasal mucosa of anaesthetized guinea pigs. Rising doses of antigen, given intraarterially or intravenously, caused proportional degrees of mast‐cell depletion in the tissue, as well as increasing intensity of the anaphylactic shock symptoms. Topical administration of different concentrations of antigen on the mucosa produced proportional degrees of mast‐cell disappearance, but gave no shock symptoms. A total mast‐cell loss in the mucosa was never seen, even following very high doses of antigen. The cell reaction was temporally closely connected to the onset of the anaphylactic shock symptoms. Maximum was found in 1 minute after intraarterial, and in 2 minutes after topical administration of antigen. The cell reaction and the corresponding anaphylactic shock could not be produced until the 9th day following the first sensitizing dose, but both could be provoked during more than 11 months after sensitization. The conclusion is drawn that the anaphylactic reaction in a guinea‐pig tissue is quantitatively reflected in the disappearance of the tissue mast cells.
Immuno‐electrophoretical Investigations of Mouse Serum Protein Fractions Obtained by Ammonium Sulphate Fractionation
Authors: Clausen J. , Heremans J.
Published: December 2008

This study contains data on 21 mouse serum proteins demonstrated by immuno‐electrophoretical analysis of normal F1 (CBA X DBA/2) mice. Supernatants and precipitates obtained with ammonium sulphate at concentrations ranging from 1.2 to 2.8 M were investigated immuno‐electrophoretically, and the precipitation range of most of the components was established. Data regarding the physicochemical properties of several mouse proteins are given as a basis for comparison with some of the better known serum proteins.
A Study of Pressure‐time Curves Obtained in the Occluded Renal Artery in Cats at Different Venous Pressures
Authors: Aarström Arne
Published: December 2008

The magnitude of the minimum arterial pressure for flow in the kidney at different venous pressures (VP) has been studied in anesthetized cats by observing the pressure drop in the renal artery after interruption of its flow for 2.0—2.5 min. At normal VP flow became “practically zero” (<0.0067 ml per min) when the renal arterial pressure (RAP) was 12.5 = 3.5 (S. D.) mm Hg and the mean arteriovenous (A‐V) pressure difference 7.6 ± 3.0 mm Hg. The cessation of flow under these conditions has been attributed to the collapsing effect upon the vessels of tissue pressure. At elevated VP the RAP usually falls to the level of VP. However, in four of twelve cases an A‐V pressure difference of 2–6 mm Hg was observed and has been attributed to a high vascular tone and/or high tissue pressure. This A‐V pressure difference at elevated VP is absent in the denervated preparation. Measures increasing vascular tone tend to augment the difference. Elevation of VP for some minutes causes an increase in resistance to flow which will influence the time course of the pressure drop and, in the case of constant volume perfusion, the value of the minimum arterial pressure for flow is elevated for 4–5 min after restoration of VP to the normal level. This effect of VP elevation is qualitatively similar to that produced at normal VP by perfusion of fluids with a lowered colloid osmotic pressure. The results seem fully explicable without invoking a hypothesis of a “venous arteriolar reflex”.
Resynthesis of Adrenaline in the Rabbit's Adrenal Medulla During Insulin‐Induced Hypoglycemia
Authors: Bygdeman S. , Euler U. S. v. , Hökfelt B.
Published: December 2008

Resynthesis of suprarenal adrenaline in rabbits during insulin hypoglycemia was calculated on the basis of the amount of adrenaline present in the gland and the amounts produced, estimated from the urinary excretion of adrenaline during a given period. It was found that depletion of adrenaline in the gland of the insulin treated animal was accompanied by a resynthesis, amounting to more than twice the average normal content in 24 hours.
Hämoglobinmenge und Blutvolumen der Ratte und ihre Beziehung zum Körpergewicht
Authors: Tribukait Bernhard
Published: December 2008

The total amount of haemoglobin and blood volume in the normal male rat has been estimated by a modified CO‐method and related to body‐weight. With increasing body‐weight the total amount of haemoglobin decreases from 0.8 g Hb/100 g body‐weight in the rat of 100–150 g to 0.68 g Hb/100 g body‐weight in the rat heavier than 450 g, and the blood volume decreases from 0.85 to 0.67 ml/100 g body‐weight. The results are compared with those of other workers and are discussed.

Hamoglobinmenge und Blutvolumen der normalen mannlichen Ratte wurden mit einer modifizierten CO‐Methode bestimmt und in Relation zum Korpergewicht gestellt. Mit steigendem Korpergewicht sinkt die Hamoglobin‐ menge von 0.8 g Hb/100 g Korpergewicht bei dem 100–150 g schweren Tier, das Blutvolumen von 0.85 auf 0.67 m1/100 g Korpergewicht. Die Resultate werden mit denen anderer Autoren verglichen und besprochen.
A Method for Recording General Activity of Mice
Authors: Arvola Alpo
Published: December 2008

The method is based on the movements of a mouse on the labile floor of the cage. The labile floor rests on a vertical metal axle in the center. Telephone exchange relays at the bottom in the center of each wall register the movements of the floor. The method is suitable for measuring activity during short periods, because the apparatus registers all movements of the mouse.
Studies of the Effect of X‐Rays on the β‐Glucuronidase Activity in the Gastric Mucous Membrane and in the Liver and of its Relation to the Glucuronide Conjugation
Authors: Hartiala K. , Näuntö V. , Rinne U. K. , Savola P.
Published: December 2008

The effect of local X‐irradiation of the liver and the stomach on the β‐glucuronidase activity was studied in rats. In the liver it was found that with the both radiation doses, 400 r and 1,200 r, there was an initial increase in the enzyme activity which was after the first day followed by a return slightly though insignificantly below the control level. After the 3rd day a new rise greatly above the control level was present. This persisted at least 2 weeks after the irradiation.

In the gastric mucosa there was only a depression in the enzyme activity beginning already 3 hours after the irradiation. The depression continued over a period of at least 12 days. Comparison of the post‐radiation, β‐glucuronidase activity and the glucuronide conjugation capacity of the same tissues revealed a parallelism for the gastric mucosa. In the liver the same stimulation and depression phases were also present for the both activities. Still they were not parallel so that the time relationships showed a distinct dissociation. The possible meaning of these relations are discussed.
The Kinetics of Na24 Flux Across Amphibian Skin and Bladder1
Authors: Hoshiko T. , Ussing H. H.
Published: December 2008

The sudden addition of Na24 to the solution bathing one side of isolated frog skin or toad urinary bladder results in a steady increase in the labelled flux with time to a final steady state value. The build‐up of the labelled flux follows a single exponential course for both influx and outflux. This is consistent with a model involving a single sodium pool in the membrane. The build‐up half‐times for toad urinary bladder and for frog skin averages about 2–5 minutes and is not accountable as diffusion delay through the connective tissue. The steady state flux, divided by the time constant of flux build‐up, gives an estimate of the minimal amount of sodium in the pool, if only one pool is responsible for the delay. The calculated sodium pool size for urinary bladder and skin is in the same range, from 0.01 to 0.42 uMeq Na/cm2. This amount exceeds any amount imaginable as residing in the 250 Å thick basement membrane which has been proposed as the site of active transport. The pool is probably located in the epithelial cells, and the actively transported sodium passes through and not between the epithelial cells.
Inhibition of Cinchophen Ulcer in Chicks with Boiled Potassium Hydrogen Saccharate
Authors: Hartiala K. , Häkkinen I.
Published: December 2008

Simultaneous feeding of saccharic acid lactone (1 1/2% of the diet) with cinchophen prevented completely the usual gastric ulcer formation up to the 10th day at which time the control group treated only with cinchophen had an ulcer in 60 per cent of the cases. At the 14th day the control group had ulcers in 85 per cent, whereas the saccharic acid treated group had ulcers and erosions in 55 per cent. Saccharic acid is known as a β‐glucuronidase enzyme inhibitor. The results are discussed in light of the possible relationship of the local glucuronide conjugation reactions and cinchophen ulcer mechanisms.
The Histamine Methylating Enzyme System in Liver
Authors: Lindahl Kerstin M.
Published: December 2008

An enzyme is described which catalyses the transfer of the methyl group of S‐adenosylmethionine to histamine at the imidazole nitrogen remote from the side chain. A method for the assay of the enzymic activity is described. The enzymic activity is enhanced with increasing pH. The influence of certain inhibitors examined suggests that the enzyme has essential sulfhydryl groups. Studies on the intracellular distribution indicate that the enzyme is localized to the soluble cytoplasm. The enzyme has been found in the liver of mouse, pig, hamster, rabbit, cat, and man.
Functional Organization of the Dorsal Spino‐Cerebellar Tract in the Cat
Authors: Lundberg A. , Winsbury G.
Published: December 2008

Recording was made from fibres in the dorsal spino‐cerebellar tract activated by group I afferents from soleus. Adequate activation through brief stretches giving selective activation of I a or I b afferents was used to differentiate between units activated by I a and I b afferents. There was no evidence of convergence of excitatory action by I a and I b afferents to the same neurones. The receptive field is often larger for neurones activated by spindle than for neurones activated by tendon organ afferents.
Vitamin D and Calcium Absorption in Parathyroidectomized Rats
Authors: Gran Fredrik C.
Published: December 2008

The absorption of calcium has been studied in parathyroidectomized rats. The destruction of the parathyroid glands did not affect the absorption of Ca. The absence of the parathyroid hormone did not impair the response of the Ca absorption to the administration of vitamin D.
Inhibitory Effects of Hydrochloric Acid in Antrum and Duodenum on Gastric Secretory Responses to Test Meal in Pavlov and Heidenhain Pouch Dogs
Authors: Andersson Sven
Published: December 2008

Instillation of hydrochloric acid into the excluded duodenum inhibits the gastric secretion stimulated by test meal in both Pavlov and Heidenhain pouch dogs. This is in accordance with the assumption by several authors that a secretion‐inhibiting mechanism is activated by an acid milieu in the duodenum. The results also show that this mechanism operates independent of the vagal nerve supply to the gastric mucosa. Perfusion of an isolated antral pouch with hydrochloric acid had lesser and irregularly occurring inhibitory effects on the secretory responses in Pavlov pouch dogs.
Circulatory Studies on Substance P in Man
Authors: Dunér Hans , Pernow Bengt
Published: December 2008

Highly purified substance P preparations were infused intravenously in doses of 0.2‐1.2 units per kg body weight per min in six healthy subjects. Red flushing, tachycardia and a rapid fall in arterial blood pressure were observed. Cardiac output was slightly increased. The effects were maximal after 1–2 min and gradually decreased during continued infusion.
On the Postnatal Development of Postural Mechanisms as Revealed by Electromyography and Myography in Decerebrate Kittens
Authors: Skoglund Sten
Published: December 2008

The present paper is one in a series of studies on the postnatal development of postural reflex activity in the kitten. Its aim is to investigate the reactions to decerebration and additional ablation of the anterior lobe of the cerebellum in these animals from birth until they are able to walk and stand. An attempt was made by electromyography and myography to trace the mechanisms behind the different reactions. It is shown that alpha rigidity is present in the newborn kitten while gamma rigidity develops later, appearing first in the forelimbs around a fortnight after birth and in the hindlimbs after three weeks. The missing gamma rigidity in the newborn animal is readily explained by the observation that no tonic stretch reflexes, as revealed by electromyography can be obtained from the muscles concerned with decerebrate rigidity. The tonic stretch reflex develops in a proximo‐distal direction in the limbs as revealed by electromyography and is earlier obtained in the alpha than the gamma animal and earlier in the forelimbs than the hindlimbs. This development thus precedes the gamma rigidity which in its development closely follows that of the animal's ability to use its limbs for walking and standing. It also runs in a cranio‐caudal direction.
The Spinal Transmission of Proprioceptive Reflexes and the Postnatal Development of Conduction Velocity in Different Hindlimb Nerves in the Kitten
Authors: Skoglund Sten
Published: December 2008

The postnatal development of the conduction velocity in different nerves of the hindlimb has been investigated in the kitten from birth to 4 months of age. It is found that the different fibre systems which have about the same conduction velocity at birth, with reference to conduction velocity, develop at different rates. Thus the large muscle afferents and efferents develop faster than the large fibres of the skin nerves and the latter faster than the gamma efferents. The conduction velocities reach adult values 3.5‐4 months after birth. It is also shown that proprioceptive reflexes can be mediated by arcs of two neurons in the newborn kitten. Furthermore the reflex time for the two‐neuron arc attains adult values when the conduction velocity of the fastest muscle afferents reaches 30 m/sec, which occurs around 20 days postnatally.
Zinc‐Induced Relaxation of Muscle Fibres
Authors: Edman K. A. Paul
Published: December 2008

The extractability of zinc from rabbit psoas muscle by glycerol‐extraction and by further treatment with EDTA and ATP has been determined as has the uptake of zinc by glycerol‐extracted fibres at bath concentrations of zinc corresponding to the free zinc ion concentration needed for induction of complete isometric relaxation of the fibres in the presence of ATP. The functionally relevant uptake of zinc needed for relaxation of extracted fibres could be covered by the total amount of zinc available in fresh muscle. Fully repeatable contraction‐relaxation cycles with glycerol‐extracted fibres in a highly plasticized state were produced with 0.6 mM total zinc simply by alternating the ATP concentration between 3 mM (relaxation) and 7 mM (contraction). The result was similar if, at constant total zinc (0.6 mM) and ATP (3 mM), 1.25 mM EDTA was alternately added (contraction) and removed (relaxation). Based upon these findings a possible mechanism for the action of zinc as a relaxing factor in vivo is presented: Relaxation is caused by inhibition of contractility by zinc; contraction is induced by release into the appropriate compartment of the fibre of a zinc‐complexing substance — ATP or a similar compound — which, after breakdown, again returns the complexed zinc with consequent re‐inhibition of contractility and, thus, relaxation.
Are Dihydroxyphenylalanine Decarboxylase and 5‐Hydroxytryptophan Decarboxylase Individual Enzymes?
Authors: ROSENGREN EVALD
Published: December 2008

Using an enzyme preparation from rabbit kidney cortex, the amino acids 3,4‐dihydroxyphenylalanine and 5‐hydroxytryptophan were found to inhibit each other's enzymatic decarboxylation competitively. Competitive inhibitions of these reactions by m‐tyrosine, o‐tyrosine, and caffeic acid were also observed. After purification of an enzyme preparation on a column of DEAE cellulose a peak appeared which contained most of the dihydroxyphenylalanine decarboxylase activity present in the extract. In this peak also nearly all the 5‐hydroxytryptophan decarboxylase activity was found. The ratio of the two activities was practically the same throughout the peak. The data were in agreement with the assumption that dihydroxyphenylalanine and 5‐hydroxytryptophan were decarboxylated by one enzyme.
Effect of Reserpine on the Adrenal Medulla of Sheep
Authors: Hillarp Nils‐Åke
Published: December 2008

The changes found in the sheep adrenal medulla on reserpine treatment were, though more pronounced, very similar to those found on indirect stimulation with insulin induced hypoglycemia. On both treatments the mechanism holding the equivalent amounts of amines and adenosinephosphates within the medullary granules is affected in such a way that the amines are released and the adenosinephosphates are broken down and/or released at the same time. In neither case do amines or adenosinephosphates accumulate in the extragranular cytoplasm and the adenine moiety of these phosphates is rapidly disposed of.
Inhibitory Effects of Hydrochloric Acid in Antrum and Duodenum on Gastric Secretory Responses to Insulin Hypoglycemia in Pavlov Pouch Dogs
Authors: Andersson Sven
Published: December 2008

Andersson, S. Inhibitory effects of hydrochloric acid in antrum and duodenum on gastric secretory responsesto insulin hypoglycemia in Pavlov pouch dogs. In Pavlov pouch dogs with the antrum and duodenum excluded from the normal gastrointestinal passage, gastric secretion was stimulated by insulin hypoglycemia. On instillation of hydrochloric acid into either the antrum or the duodenum the secretory responses were markedly inhibited. The inhibitory mechanisms are discussed.
Electrophysiological Studies on Gamma Motoneurones
Authors: Eccles J. C. , Eccles Rosamond M. , Iggo A. , Lundberg A.
Published: December 2008

Eccles, J. C., R. M. Eccles, A. Iggo and A. Lundberg. Electsophysiological studies on gamma motoneurones. Gamma motoneurones supplying the muscle spindles of limb muscles of cats have been investigated by microelectrodes either extracellular or intracellular, and shown to lie interspersed with the alpha motoneurones of that muscle. The spike potential of the gamma motoneurones resembles that of alpha motoneurones both in having an ‐IS–SD composition and in being followed by a long after‐hyperpolarization. When activated either by repetitive antidromic impulses, or by a prolonged depolarizing current, the gamma motoneurones give some spike potentials at much higher frequencies than the alpha. It was confirmed that the gamma motoneurones differ from the alpha in receiving no monosynaptic excitatory action, but there are polysynaptic excitatory and inhibitory actions from other afferents.
Post‐Stimulatory Electrical Activity in the Preoptic “Heat Loss Centre” Concomitant with Persistent Thermoregulatory Response
Authors: Anderson B. , Persson N. , Ström L.
Published: December 2008

Anderson, B., N. Persson and L. Ström. Post‐stimulatory electrical activity in the preoptic “heat loss centre” concomitant with persistent thermoregulatory response.

Thermoregulatory response remaining after electrical stimulation of the preoptic “heat loss centre” was studied in nonanaesthetized goats. The intensity and the duration of the response was dependent upon the external and the internal temperatures of the animals. Recording of the electrical activity in the “heat loss centre” produced evidence that the response studied was in some way related to a long‐lasting after‐discharge recorded from the stimulated part of the brain stem.
The Effect of Blood Volume Variations on the Pulse Rate in Supine and Upright Positions and During Exercise1
Authors: Gullbring B. , Holmgren A. , Sjöstrand T. , Strandell T.
Published: December 2008

GullbringB., A. Holmgren, T. Sjöstrandand T. Strandell.The effect of blood volume variations on the pulse rate in supim and upright positions and during txercice.

The effect of bleeding of about 10 per cent of the blood volume and reinfusion of this quantity of blood seven days later was studied in six male subjects. The study includes determination of the pulse rate at rest in supine and upright positions and during exercise on a bicycle ergometer. The physical working capacity (PWC170) was computed from the pulse rates during work. The pulse rate in upright position and during exercise increases and PWC170decreases immediately after the bleeding. During the next few days PWC170increases and the pulse rate in upright position and during exercise decreases, while the pulse rate in supine position appeared to increase. On the sixth day PWC170was found to be higher and the pulse rate in supine and upright positions and during exercise to be lower than before the bleeding. Reinfusion of the blood seemed to produce a further moderate increase in PWC170. The decrease in PWC170after the bleeding corresponded, on the whole, to the average relation in different individuals between PWC170and the total amount of hemoglobin. The respiratory rate during exercise increased after the bleeding and also showed the same tendency as the pulse rate did during exercise and in upright position during the next few days.
Effect of Training on Work Capacity, Total Hemoglobin, Blood Volume, Heart Volume and Pulse Rate in Recumbent and Upright Positions1
Authors: Holmgren A. , Mossfeldt F. , Sjöstrand T. , Ström G.
Published: December 2008

Holmgren, A., F. Mossfeldt, T. Sjötrand and G. Ström. Effect of training on work capacib, total hemoglobin, blood volume, heart volume and pulse rate in recumbent and upright positions.

The effect of training, either with gymnastic exercises and running once or twice a week for several months, or with daily skiing in mountainous terrain for eight to ten days, has been studied on altogether 87 test subjects. Determinations were made of work capacity, expressed as work on a bicycle ergometer at a pulse rate of 170 and at relative steady state (PWC170 S), total amount of hemoglobin (THb) and blood volume, heart volume in recumbent position, and pulse rate at rest in recumbent and upright positions.

The intermittent long‐term training was found to cause an increase in PWC170 S, THb and blood volume, and a decrease in pulse rate in recumbent position. The heart volume showed an insignificant average increase in two subjects groups, and decreased slightly in a group of middle‐aged men. The relation between PWC170 S and THb or blood volume corresponded, both before and after the training, to the relationship earlier demonstrated in a series of individuals differing with respect to age, body size, sex and degree of physical training. The continuous short‐term training was also found to induce an average increase in the PWC170 S, blood volume and THb, and a decrease
Inhibition of Thrombocytopenia and 5‐Hydroxytryptamine Release in Anaphylactic Shock by Heparin
Authors: Johansson Stig‐Arne
Published: December 2008

After anaphylactic shock increased amounts of 5‐HT in plasma, and lung tissues, a decrease in the circulating number of platelets and increase in the urinary excretion of 5‐hydroxyindole acetic acid (5‐HIAA) were found but no alteration in the amounts of 5‐HT in the intestines. Pretreatment of the animals with heparin prevented these effects and also the release of 5‐HT from cells in sensitized blood after addition of a specific antigen to citrate blood in vitro. Heparin also inhibits the ability of platelets to adsorb 5‐HT in vitro. Dialysis experiments, coagulation time measurements and intravenous injections of 5‐HT on heparin treated animals indicate that heparin has no ability to bind 5‐HT in blood. It is suggested that heparin, being a strongly acid polyelectrolyte, acts on the platelets and their ability to absorb and release 5‐HT and prevents the onset of a transient intravascular coagulation during anaphylaxis.
“Bound” and “Free” Catecholamines in the Brain
Authors: Bertler Å. , Hillarp N.‐Å. , Rosencren E.
Published: December 2008

The major portion of the noradrenaline in the rabbit hypothalamus was recovered in the particulate fraction of homogenates in 0.3 M sucrose. In contrast to this, the dopamine in the caudate nuclei of rabbit and cat was to the largest part found in the high‐speed supernatant. The amine distribution did not seem to be materially influenced by the use of different homogenization media. Neither were any obvious changes in the distribution seen after administration of iproniazid or reserpine. The dopamine formed in the hypothalamus after an injection of L‐dopa was found to be “particle‐bound” to a rather large extent.
Some Characteristics of the Hypothalamic “Drinking Centre” in the Goat as Shown by the Use of Permanent Electrodes
Authors: Anderson B. , Larsson S. , Person N.
Published: December 2008

The response to electrical stimulation of the “drinking centre” was studied in one goat for a period of six months. Emotional factors and hydration were found to increase the stimulus threshold for drinking. Drinking continued for different lengths of time after cessation of stimulation. The after‐effect which may be due to an after‐discharge in the stimulated area of the hypothalamus was inhibited by the previous injection of amphetamine or the drinking of cold water. On repeated stimulations the animal learned to overcome a simple obstacle in order to gain access to the drinking water. If the goat was not allowed to drink, the stimulations elicited a typical “displacement reaction”. Prolonged strong stimulations of the “drinking centre” were not observed to alter the electrolyte metabolism significantly.
Alveolo‐Arterial Gas Exchange at Rest and During Work at Different O2, Tensions
Authors: Asmussen Erlinc , Nielsen Marius
Published: December 2008

The mean alveolar and the arterial gas tensions in healthy young male subjects have been determined at rest and during muscular exercise of varying intensities up to maximal work. Determinations were made while the subjects were breathing air containing 33 to 50 per cent, 21 per cent and 12 per cent oxygen. From the experimental data the alveolo‐arterial oxygen tension differences and the arterial oxygen deficits (i. e. the difference between the oxygen content of blood in full equilibrium with the mean alveolar air and the actual oxygen content of peripheral arterial blood) were calculated. Under the assumption that the Bohr integration procedure can be used for determining the mean pulmonary capillary PO2 in the human lung it can be concluded that the arterial oxygen deficit when breathing normal air both at rest and during maximal work is caused by true venous admixture (anatomical shunts) and the effect of uneven distribution in the lungs, and it is found that about 80 per cent is due to the distribution effect and the remaining 20 per cent to the true venous admixture. Further, the effect of the distribution factor at low oxygen pressures increases manifold as compared with the effect at normal O2 pressure. The large arterial O2 deficit found in the low O2 experiments (in ml per min equal to 62 and 36 per cent of the total O2 uptake at rest, respectively during maximal work) can, therefore, be explained by the true venous admixture and the greatly increased effect of the distribution factor. According to this view it is not possible to determine the lung diffusion capacity for O2 on the basis of the alveolo‐end pulmonary capillary O2 gradient by the procedure of Riley and Cournand (which assumes a constant effect of the distribution factor at high and low oxygen tension) or by the procedure of Bartelset al. (which does not take the distribution factor into account).
Three Ascending Spinal Pathways in the Dorsal Part of the Lateral Funiculus
Authors: Lundberg A. , Oscarsson O.
Published: December 2008

Lundberg, A. and O. Oscarsson. Three ascending spinal pathways in the dorsal part of the lateral funiculus.

Three pathways with axons ascending in the dorsal part of the lateral funicle have been identified as not belonging to the dorsal spino‐cerebellar tract because the axons could be activated on stimulation of the lateral funicle in L5 below the caudal level of Clarke's column but not antidromically from the anterior cerebellar lobe cortex. One of these pathways is located medial to the dorsal spino‐cerebellar tract and is activated exclusively by tactile stimuli from small skin fields.
Activation of the Dentate Area by Septal Stimulation
Authors: Andersen Per , Bruland Helce , Kaada Birger R.
Published: December 2008

Andersen, P., H. Bruland, and B. R. Kaada, Activation of the dentate area by septal stimulation.

In rabbits under urethane‐chloralose anesthesia potentials were recorded bilaterally from the dentate area in response to stimulation of the large‐celled posterior part of the medial septal nucleus. The septo‐dentate response consisted of an initial negative spike followed by a slower positive wave. On the basis of recordings from the various cell layers, excitability properties, resistance to anoxia and repetitive stimulation, the initial spike is interpreted as discharges of the dentate granule cells, monosynaptically excited. The following positive wave may partly represent the subsequent spread of excitation along the dendrites of the granule cells, and partly the activation of CA4 neurons.–Stimulation of the contralateral field CA3 of the hippocampus evoked within the dentate area a potential similar in form, but with a greater amplitude and shorter latency than the septo‐dentate response. This crossed CA3‐dentate potential is similarly most likely due to activation of the same granule cells. The crossed projection appears to be more efficient and consists of thicker fibres than the septo‐dentate path.
Activation of the Field CAI of the Hippocampus by Septal Stimulation
Authors: Andersen Per , Bruland Helce , Kaada Bircer R.
Published: December 2008

Andersen P., H. Bruland B. R. Kaada. Activation of the field CA1 of the hippocampus by septal stimulation.

In rabbits under urethane‐chloralose anesthesia the existence of a septo‐hippocampal projection has been verified by the evoked potential method. Its origin is the magnocellular medial septal nucleus. These septo‐fugal fibres activate the basal parts of the apical dendrites and/or the soma of the CAI neurons, probably by a mono‐synaptic route. By repetitive stimulation and by strychnine the depolarized area of the CAI neurons may increase, by anoxia it may decrease. Thus, according to the excitability level, a smaller or greater part of the apical dendrites may initiate spikes of an all‐or‐none character.
Does the Urinary Excretion of Imidazole Acetic Acid Reflect the Endogenous Histamine Metabolism in Man?
Authors: Dunér Hans , Liljedahl Sten Otto , Pernow Benct
Published: December 2008

Dunér H., S. O. Liljedahl B. Pernow. Does the urinary excretion of imidazole acetic acid reflect the endogenous histamine mtabolism in man?

The urinary excretion of free and conjugated histamine, histidine and imidazole acetic acid (ImAA) was studied in four healthy subjects and four patients with severe burns. ImAA was found to be a normal constituent of human urine. In the cases of burn, where the histamine excretion was increased during the first days after the accident, the ImAA excretion was normal and showed no significant variations. Administration of histamine or histidine gave a slight increase in the excretion of ImAA.
Transmission and Reflection of High Explosive Shock Waves in Bone
Authors: Clemedson Carl‐Johan , Jönsson Arne
Published: December 2008

Clemedson C.‐J. and A. Jönsson. Transmission and rejection of high explosive shock waves in bone.

Various kinds of bone such as femur, ribs with intercostal muscles, sternum with ribs and intercostal muscles and spinal column from ox, and femur, and femur + tibia with intact stifle joint from horse were exposed to high explosive air shock waves in a detonation chamber. The patterns of the pressure wave in the bone caused by the shock wave were recorded piezo‐electrically by means of a barium titanate pressure transducer. The transmitted wave consists of two parts. The first one, called the front pressure wave, is due entirely to the impact of the air shock wave on the front surface of the object. The second part is due mainly to the progressive loading of the static pressure in the air shock wave as it passes by the object. Due to the inhomogeneity of bone, the transmitted part of the incident shock wave is more or less changed since it is diffused and broken up by reflection and scattering. It is less changed in a long bone such as femur than in e. g. sternum or the spinal column. It is strongly changed by the passage between the two bones in a joint. Strong reflections occur at the bone surface. The velocity of the wave is about 3,500 m/sec. in the long bones. In the spinal column and sternum it is considerably lower and is dependent on the length of path covered.
Electromyographic Findings in Experimental Botulinum Intoxication
Authors: Josefsson J.‐O. , Thesleff S.
Published: December 2008

JosefssonJ.‐O. and S. Thesleff.Electromyographic findings in experimental botulinum intoxication.

The electrical activity of botulinum intoxicated skeletal muscle was examined in the rabbit by the use of electromyography. 5 to 6 days after an intramuscular injection of the toxin, fibrillation potentials appeared and persisted for a period of at least 60 days. The potentials were similar in amplitude and time course to those recorded following motor nerve degeneration. Botulinum toxin, however, is known not to affect the morphological structure of the motor nerve and its terminals. Its sole action is to block transmitter release selectively from cholinergic nerve endings. Our results therefore suggest that in nerve degeneration lack of transmitter release is primarily responsible for initiating the process which produces the electromyographic pattern typical of denervation.
Tyramine Effects on Catechol Amine Release from Spleen and Adrenals in the Cat
Authors: Stjärne L.
Published: December 2008

Stjärne L. Tyramine effects on catechol amine release from spleen and adrenals in the cat.

Recent studies on the sympathomimetic effect of tyramine suggest that this substance may act by liberating noradrenaline. In the present experiments direct bioassay of the venous effluents from the spleen and the adrenals of the cat demonstrated that the noradrenaline level in splenic vein blood was elevated by tyramine, whereas in the adrenal venous blood both the adrenaline and noradrenaline levels were either unchanged or depressed. The discrepancy between the effects of tyramine on these two systems is discussed. It is concluded that in the spleen tyramine may act either by releasing noradrenaline from the intra‐axonal storage granules, or by making extragranular noradrenaline, bound to some structure probably in close relation to the axone, available to the receptors.
Distribution and Concentration of Adrenaline and Noradrenaline in the Adrenal Medulla of the Rat Following Reserpine‐Induced Depletion
Authors: Eränkö Olavi , Hopsu Väinö
Published: December 2008

Eränkö O. and V. Hopsu. Distribution and concentration of adrenaline and noradrenaline in the adrenal medulla of the rat following reserpine‐induced depletion.

Adrenaline and noradrenaline concentrations in the adrenal medulla were determined after chromatographic separation by fluorometry. The chromaffin reaction, the iodate reaction and formalin‐induced fluorescence were used as histochemical reactions and their intensities in the sections were quantitatively measured by microphotometry. Four mg/kg of reserpine daily for 4 days caused a pronounced loss of adrenaline and noradrenaline and recovery took about 3 weeks. During the recovery adrenaline and noradrenaline concentrations increased proportionally. The chemical and the histochemical measurements gave identical results. There was no evidence of local resynthesis of noradrenaline in excess of that of adrenaline. The results are at variance with observations reported earlier from other laboratories.
The Urinary Excretion of Galactose and its Significance in Clinical Intravenous Galactose Tolerance Tests
Authors: Tygstrup Niels
Published: December 2008

Tygstrup N. The urinary excretion of galactose and its significance in clinical intravenous galactose tolerance tests.

The disappearance of galactose from the blood after intravenous administration may be used for measurement of the liver function, if correction for the urinary loss of galactose is made. The present study was performed in order to determine the significance of this loss. It was found that urinary excretion of galactose was unimportant in relation to hepatic elimination at plasma concentrations below about 500 mg/l (approximately 3 per cent of the total elimination), but at higher concentrations the ratio between urinary excretion and hepatic elimination increased, as the former rises with the concentration, and the latter remains constant. After a single injection of about 500 mg/kg body weight on an average 10 per cent of this amount was excreted in normal subjects as well as in patients with cirrhosis. This percentage could be used for a practical calculation of the contribution of the urinary loss to the total elimination rate of galactose during the interval in which the latter remains essentially constant. The experiments indicate a low renal threshold for galactose, but no evidence for a reabsorption Tm was found within the range of plasma concentrations studied (up to 3,000 mg/l). The renal clearance of galactose was significantly decreased in patients with cirrhosis. The implications of these findings for the calculation of the maximal hepatic galactose elimination rate from the plasma concentration curve following a single injection are examined in an appendix.