bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effect of Tyramine, Reserpine and Cocaine on the Noradrenaline Release and Uptake of the Perfused Rabbit Kidney
Authors: Inouye A. , Tanaka I. 
Published: December 2008

AbstractPerfusion of isolated rabbit kidneys for 120–150 min with Tyrode solution containing 0.05 per cent iproniazide caused no change of the normal noradrenaline (NA) content. Addition of NA to the perfusion fluid caused an uptake of NA approximately proportional to the NA concentration. The major part of the NA retained was removed by subsequent perfusion with NA‐free Tyrode solution. Perfusion with tyramine 10‐4M removed a large part of the renal NA, even in the presence of NA in the perfusion fluid. Reserpine 4 × 10‐5M did not significantly release NA or alter the renal NA content, but diminished the NA uptake from a solution containing NA. Cocaine caused a moderate release of NA and partially prevented the NA uptake while it hardly caused any loss in the renal NA content, suggesting some NA resynthesis.
Studies on the Elimination of Exogenous Lipids from the Blood Stream. Determination and Separation of the Plasma Triglycerides after Single Injection of a Fat Emulsion in Man
Authors: Hallberg Dag 
Published: December 2008

AbstractSingle injection of a fat emulsion into the blood stream in man resulted into a complex eliminationcurve, when total triglyceride (TG) concentration in plasma was followed. The complexity of the curve was studied by separation of the plasma TG either by centrifugation or by a density gradient method with polyvinylpyrrolidone (PVP). Centri‐fugation of plasma at 48.6 times 104 G‐minutes did not solve the complex curves. The PVP method gave three TG fractions: fat emulsion in the top fraction and endogenous plasma TG in the bottom and middle fraction. Elimination curves obtained with the PVP method were compos‐site. The TG concentration in the top fraction, which was zero in fasting plasma, increased after injection of the emulsion and then decreased. This decrease could be resolved into a linear phase at high TG concentration and an exponential phase at lower concentrations. The curve for the bottom fraction showed a slowly increasing concentration and that for the middle fraction showed a rapid increase followed by a decrease. The complex appearance of the curve without fractionation of the TG depends on these two latter lipid fractions which change in concentration during the elimination. The difficulties in interpreting the elimination curves obtained by the centrifugation method was with the gradient shown to depend on heterogeneity in the top TG fraction obtained by centrifugation.
Presynaptic Depolarization of Group I Muscle Afferents by Gontralateral Afferent Volleys
Authors: Devanandan M. S. , Holmqvist Birgitta , Yokota T. 
Published: December 2008

AbstractPresynaptic depolarization of group I afferents produced by volleys in contralateral hind limb nerves has been investigated. It was found that a train of volleys in contralateral muscle or skin nerves did not alter the excitability of the Ia fibres or the size of the monosynaptic EPSP in motoneurones, i. e., there is no contralateral presynaptic inhibitory action onto group Ia fibres. A train of volleys in contralateral muscle and skin nerves increased the excitability of the contralateral Ib fibres to the flexors and extensors. The time course of the increased excitability had a latency of 10–30 msec, a slow rising phase, a late maximum at 50–80 msec, and a duration of about 150 msec. The crossed presynaptic actions originated from high threshold (group II and III) muscle afferent and cutaneous fibres. The results also indicate that Ib fibres may have a depolarizing action onto the contralateral Ib nerve terminals.
Peripheral Resistance Response to Occlusion of Visceral Arteries
Authors: Nissen Ole I. 
Published: December 2008

AbstractIn order to compare the effect of visceral and carotid sinus hypotension on the resistance vessels the peripheral resistance in 3 areas (hind body, kidneys and head) in the cat has been investigated by means of the constant perfusion rate technique during occlusion and desocclusion of visceral (coeliac, superior mesenteric and renal) arteries and of the carotid arteries. In all 3 areas clamping of the visceral arteries provoked a vasodilatation whereas a vasoconstriction in the hind body and kidney was observed during carotid artery occlusion. The clampings always produced significant rises in the general arterial blood pressure. The pressor response caused by visceral artery occlusion thus is produced in spite of a widespread dilatation of the resistance vessels—not as a consequence of a constriction in the same vessels. Denervation of the carotid sinuses plus section of the vago‐sympathetic trunks nearly always abolished the vasodilatation. Stabilising the blood pressure by means of a compensating device always abolished the vasodilatation during visceral artery occlusion. Under these circumstances the vasodilatation was not replaced by a vasoconstriction in the periphery. It has thus not been possible to demonstrate baroreceptor activity in the visceral arteries even under circumstances where the activity of the sino‐cardio‐aortic baroreceptor reflexes was eliminated.
Energy Cost of Alternating Positive and Negative Work
Authors: Hesser C. M. 
Published: December 2008

AbstractThe energy cost of walking up and down a A‐shaped, 1 m high staircase was studied in 10 male and 10 female subjects in terms of the O2 requirement for performing the work under truly aerobic conditions. Two different speeds of walking were used, yielding external work loads of k × 14.7 and k × 26.7 kpm/min (k = body weight of individual in kg) in both the positive and negative phases. At the lower speed the net O2 cost per kg b. w. averaged 16.8 ml/min, independent of sex; at the higher speed the corresponding value was 33.0 ml/min in the men, and 32.0 ml/min in the women. From these values the average physiological load was estimated to k × 8.2 kpm/min for men and women at the lower speed, and to k × 16.2 and k × 15.7 kpm/min for men and women, respectively, at the higher speed. The ratio of O2 costs for the positive and negative works approximated 8: 1 at the lower speed, and 5: 1 at the higher speed. During each period of positive work the calculated O2 demand of a 70 kg man exceeded the O2 supply to the working muscles by about 60 ml at both speeds. This O2 debt of 60 ml could be contracted without any increment in the lactacid O2 debt and supports the notion that a certain amount of O2 can be released from the myoglobin O2 store before anaerobic processes become involved. The O2 capacity of this aerobic debt mechanism was calculated to be in the order of 3 ml per kg of active muscle tissue. Evidence is presented that, in the steady state, the upper limit for performing work under truly aerobic conditions corresponds to about 70 per cent of the maximal O2 consumption.
Functional Qualities of Small Blood Vessels in Tissue Injured by Freezing and Thawing
Authors: Reite Ola Bodvar 
Published: December 2008

AbstractRabbit ears were frozen to ‐10°C and thawed in vivo, uniform freezing being secured by vascular occlusion during the freezing procedure. Following thawing and re‐establishment of blood flow the ears showed circulatory changes. Hyperemia, edema formation and stasis with subsequent recovery were observed. Studies were performed to test the functional qualities of the small blood vessels of the affected area. The vascular endothelium, the smooth muscles and the sympathetic vasoconstrictor nerve fibres were examined.The endothelial regenerative power appeared unaltered as revealed by the in growth of new capillaries into transparent ear chambers inserted in the injured ears. Intradermal injections of histamine and bradykinin caused a local increase in the exudation of Evan's blue from the frostbitten blood vessels whereas intradermally injected acetylcholine did not. Stimulation of vasoconstrictor nerve fibres or intravascular injections of adrenaline produced vasoconstriction measured as a decrease in blood flow through the previously frozen ear.It is concluded that the blood vessel walls have retained their functional qualities and that the observed circulatory changes can be induced by endogenous substances liberated or activated consequent to injury.
Relationship between Osmotic Reactions and Active Sodium Transport in the Frog Skin Epithelium
Authors: Ussing Hans H. 
Published: December 2008

AbstractThe osmotic behaviour of the skin epithelium of the brown frog (R. temp.) has been investigated by microscopic measurement of thickness under different experimental conditions. Simultaneous measurements of skin potential and short‐circuit current were made. Epithelial swelling was induced by hypotonicity of the inside but not the outside bathing solution, whereas shrinkage was brought about by hypertonicity of either inside or outside bathing solutions, although the tonicity of the inside bathing solution dominates the osmotic reponse. Shrinkage can also be induced by lowering the potassium concentration of the inside solution. Complex shrinkage and swelling reactions are produced by addition of diffusible substances like urea to either bathing solution. In practically every instance shrinkage leads to inhibition of the short‐circuit current (and thus of the active sodium transport), whereas swelling of the epithelium gives rise to increased active sodium transport. The skin potential is related to swelling and shrinkage in a more involved fashion. In general hypertonicity of the outside bathing solution leads to a violent drop in skin potential. The observations indicate that hypertonicity of the outside solution increases the permeability of the outer epithelial boundary to passively diffusing electrolytes and to water.
The Importance of the Legs in the Thermoregulation of Birds
Authors: Steen Inoer , Steen J. B. 
Published: December 2008

AbstractThe proportion of the total heat production of herons and gulls which at ambient temperatures ranging from—10° C to 35° C is dissipated to cold water or air surrounding their legs has been measured. At low ambient temperatures less than 10 % of the metabolic heat is lost from the legs. At higher ambient temperatures an increasing proportion of the metabolic heat is lost from the legs and at 35° C almost the entire heat production is dissipated through the legs. Heat loss to water was found to be about four times higher than to air of the same temperature. The degree of heat loss from the legs was shown to react within seconds to changes in ambient temperature. Likewise, panting stopped immediately when the legs were irregated by cold water. It is concluded that the naked legs of these birds serve as controlled heat conduits of great importance in thermoregulation.
Vasodilating Action of Substance P in the Human Forearm
Authors: Löfström Bertil , Pernow Bengt , Wahren John 
Published: December 2008

AbstractThe vasodilator activity of substance P in the human forearm has been studied using venous occlusion plethysmography. The effects have been compared to those of bradykinin. The compounds were given as single injections or infusions into the brachial artery or the antecubital vein. I.a. administration caused a significant increase in skin and muscle blood flow in doses of more than 0.5 units of substance P per min. The oxygen saturation of blood from both deep and superficial veins of the forearm increased. These effects were not influenced bvatropine, antihistaminics or guanethidine. Stellate ganglion block increased the resting blood flow as well as the vasodilating action of both polypeptides. I.v. infusion c f substance P and bradykinin also caused an increase in forearm blood flow coincident with tachycardia and flushing of the face and the neck. During substance P infusion the increase in forearm blood flow and flushing appeared simultaneously, while bradykinin caused an increase in the forearm blood flow only in doses which were almost intolerable for the subjects due to severe pulsations and flushing of the skin of the head and the neck. The ratios between equieffective doses of substance P and bradykinin on the forearm blood flow were about 1:10 at i.a. infusion and about 1:200 at i.v. infusion.
Uptake and Exchange of Catecholamines in Rat Tissues after Administration of d‐and 1‐Adrenaline
Authors: Westfall T. C. 
Published: December 2008

AbstractThe effect of d‐and 1‐adrenaline (A) on the catecholamine (CA) content of heart and liver of the rat was studied at various times following i.m. administration. It was observed that both isomers are readily taken up by these tissues and exchanged for the normal neurotransmitter, noradrenaline (NA). The present experiments also present evidence for the uptake of both d‐and 1‐A into subcellular storage granules. The fall in the NA content of the organs was accompanied by an increased urinary excretion of NA. The present experiments also indicate that there is a slight steric preference for the storage in favor of the 1‐isomer.
Vagal Release of Gastrin in Cats Following Reserpine1
Authors: Emås Sverre , Fyrö Bengt 
Published: December 2008

AbstractReserpine treatment of nonanesthetized cats has previously been shown to sensitize the HCl‐secreting cells to injected gastrin, probably by a centrally induced enhancement of vagal tone. Indications were obtained also of an interference with the gastrin mechanism. Since vagal impulses are considered to be able to release gastrin, the effect of reserpine on the gastrin activity of the antral and duodenal mucosa has been investigated. Gastrin was extracted from the mucosae of reserpine‐injected and untreated cats and the secretory activity of the preparations determined on nonanesthetized gastric nstula cats. An intramuscular injection of 0.10 mg of reserpine per kg b. w. reduced the gastrin activity of the antral mucosa by about 60 per cent in 24 hrs. Neither a 20‐fold increase in dose nor repetition of the injection of 0.10 mg per kg every 24 hrs for 2 or 4 days produced any further reduction and the gastrin activity returned to normal level despite repeated injections for 8 days. An intravenous infusion of 0.03 mg of reserpine per kg, which produces gastric hypersecretion of acid for several hours, caused no significant alteration in the gastrin activity of the antral mucosa. The gastrin activity of the duodenal mucosa amounted to about one‐tenth the activity of the antral mucosa and was reduced by 0.10 mg of reserpine i. m. daily for 2 or 4 days. Bilateral vagotomy did not alter the gastrin activity of either the antral or doudenal mucosa nor did the i. m. injection of 0.10 mg of reserpine per kg daily for 2 days in vagotomized cats. It is suggested that reserpine causes release of antral and duodenal gastrin by central vagal activation. The significance of gastrin release as a mechanism by which reserpine activates the HCl‐secreting cells is discussed.
Tissue Eosinophils of Rat under the Influence of Gysteine, Lysine and X‐Irradiation1
Authors: Holsti Lars R. , Rytömaa Tapio 
Published: December 2008

AbstractCysteine and lysine were given to rats by stomach tube either alone or before whole body irradiation and the tissue eosinophils were counted. Repeated daily administration of cysteine and lysine for a week caused a significant decrease in the eosinophil count of the skin, duodenum and colon. Short term amino acid treatment caused no changes in the tissue eosinophil count. Whole body irradiation alone and after amino acid pre‐treatment also caused a significant decline in the tissue eosinophil count. This concurs with observations that long‐term treatment with ACTH and cortisone lowers the number of tissue eosinophils (Wegelius and Teir 1958, Räsänen 1961). The principal extra‐medullary amount of eosinophils of the organism is in the tissues. The significance of these cells for the organism is that they constitute one of its defensive and protective mechanisms (Rytömaa 1960). There seems to be a relationship between the number of tissue eosinophils and the radio‐protective effect of cysteine and lysine established earlier (Holsti 1960).
The Metabolism of Fatty Acids in the Rat III. Arachidic Acid
Authors: Göransson Göran 
Published: December 2008

Abstract1‐C14‐Arachidic acid and 9–10‐H3‐palmitic acid in rat serum were simultaneously injected into fasted and refed male rats and the blood and tissue distribution of radioactivity were studied. The results suggest that, in spite of quantitative differences, arachidic acid enters the same principal pathways as palmitic acid. The labeled arachidic acid disappeared more slowly from the blood than did the palmitic acid. Two minutes after the injection slightly less arachidic than palmitic acid label was recovered from the whole animal. In the liver, more of the esterified arachidic acid than of the palmitic acid radioactivity was present in triglyceride and less in phospholipicl.
The Metabolism of Fatty Acids in the Rat V. Palmitoleic Acid
Authors: Göransson Goran 
Published: December 2008

AbstractH3‐palmitoleic and 1‐C14‐palmitic acid were simultaneously injected into fasted or refed male rats and the disappearance of label from the blood, the tissue distribution of label after 2 and 320 min as well as the recirculation of label into the blood were studied. It was found that the injected palmitoleic acid was taken up and oxidized at a higher rate by the cells than was the injected palmitic acid. At short times, more H3‐label than C14‐label was found in the neutral fat in most tissues, indicating that palmitoleic acid is preferentially incorporated into the glycerides. The total lipids of the heart contained more palmitoleic acid label than palmitic acid label in the refed rats. In all the mentioned respects palmitoleic acid was metabolized in the same way as oleic acid.A useful method for biosynthesis of labeled palmitoleic acid from labeled palmitic acid is reported.
Supraspinal Control of the Intestino‐intestinal Inhibitory Reflex
Authors: Johansson Börje , Jonsson Olof , Ljung Bengt 
Published: December 2008

AbstractExperiments were performed on chloraloseurethane‐anesthetized, vagotomized cats. Changes in the level of adrenomedullary hormones were prevented. Distension of a segment of distal jejunum produced a prompt decrease in tone and rhythmicity in the proximal jejunum. This so called intestino‐intestinal inhibition is a propriospinal reflex response apparently mediated by sympathetic efferents. Electrical stimulation in the mediocaudal part of the rhomboid fossa was found to ‘block’ this spinal intestinoinhibitory reflex. The fact that bulbar stimulation alone sometimes produced an increase in gut motility seemed to be due to suppression of a prevailing activity in the propriospinal reflex. When there was a low level of such activity medullary stimulation per se had little or no effect on intestinal motility. It is suggested that the supraspinal structures exert an inhibitory influence on impulse transmission in the propriospinal intestino‐inhibitory reflex arcs.
Responsiveness of the Erythron to Variations of Oxygen Tension in the Chick Embryo and Young Chicken
Authors: Jalavisto Eeva , Kuorinka I. , Kyllästinen M. 
Published: December 2008

AbstractThe reactivity of the chick embryo erythron to varying ambient oxygen concentrations was investigated. The hemoglobin (Hb) concentration, the hematocrit and red cell count were determined in embryos incubated in 40 % O2, air and 15 % O2. The age of the embryos varied between 9 and 19 days. The results indicated that embryos weighing less than 7 g and approximately less than 14 days old do not increase their Hb, hematocrit or erythrocyte count when exposed to 15 % O2. In embryos aged 16 days or over the 15 % O2 exerts a stimulatory effect: the Hb and hematocrit values exceed those found in the embryos incubated in 40 % O2. The mean corpuscular volume and the mean corpuscular Hb are not affected by differences in ambient oxygen concentrations.It is pointed out that the 15th day of incubation seems to represent a critical phase in chick embryo development—it is not only approximately the date when myeloid erythropoiesis begins to dominate, but also the date when, for instance, some polyamines begin to be synthetized and the hypophysis becomes functionally active.
Central Control of Static and Dynamic Sensitivities of Muscle Spindle Primary Endings
Authors: Appelberg B. , Emonet‐Denand Françoise 
Published: December 2008

AbstractIn cats under light Nembutal/urethane anesthesia, electrical stimulation within a restricted area in the mesencephalon caused a strong increase of the dynamic sensitivity of extensor as well as flexor muscle spindles. Static effects were usually weak from this region and sometimes inhibition of static activity was evoked simultaneously with dynamic activation. From neighbouring regions augmentation or inhibition of static sensitivity was obtained without effects on the dynamic sensitivity. By using small muscles and recording electromyograms it could be shown that the effects on the spindles were elicited without simultaneous extrafusal activation. The conclusion is reached, that central stimulation in appropriate regions may, in a rather selective way, activate different populations of gamma efferent fibres having either a dynamic or a static effect on the spindles. The results are discussed in relation to recent investigations of the effect of single gamma fibre stimulation on spindle sensitivity.
The Effect of Small Doses of Chemically Pure Secretin on the Volume and Bicarbonate Output of the Pancreatic Juice in Dogs
Authors: SÄTERI H. , THULIN L. , WELANDER B. 
Published: December 2008

AbstractSäteri, H., L. Thulin and B. Welander. The effect of small doses of chemically pure secretin on the volume and bicarbonate output of the pancreatic juice in dogs. Acta physiol. scand. 1965. 64. 106–108. The volume and bicarbonate output of the pancreatic juice during fasting and during infusion of chemically pure secretin at doses without effect on the liver were studied by a non‐surgical method. Eight experiments were made in 2 unanesthetized dogs. The doses ranged from 0.25 to 1.5 clinical units per kg b. w. and hr. At the smaller doses there was only a slight increase of the volume and the bicarbonate output. At the larger doses the maximum volume, 25 ml per 30 min, was about 3 times the initial and the maximum bicarbonate output, 1.4–2.7 meq per 30 min, about 50 times the initial in one dog and about 10 times in the other.
Effect of Potassium on the Movement of Water Across the Isolated Amphibian Skin
Authors: SHARE LEONARD , USSING HANS H. 
Published: December 2008

AbstractShare, L. and H. H. Ussing. Effect of potassium on the movement of water across the isolated amphibian skin. Acta physiol. scand. 1965. 64. 109–118. – Substitution of potassium for sodium in the Ringer bathing the inner surface of the isolated toad skin resulted in an increased net movement of water across the skin along an osmotic gradient. This effect was somewhat smaller than the response to vasopressin, although the responses to the high potassium treatment and to vasopressin were not additive. Substitution of sulfate for chloride as the major anion in the Ringer did not modify the relative increase in water movement following either the potassium or vasopressin treatments, although the magnitude of the water movements were greater with the latter anion. Low pH blocked the response to vasopressin but not to potassium. Changes in the concentration of calcium in either inner or outer solutions were without effect on the responses to either potassium or vasopressin. Parallel seasonal changes in the responsiveness of the toad skin to potassium and vasopressin were ohserved.