bluuebunny/crossref_metadata_2025 huggingface dataset:
Refractory Period and Conduction Velocity of the Striated Muscle Fibre*
Authors: Buchthal Fritz , Engbæk Lise
Published: December 2008

Buchthal, F. and L. Engbæek, Refractory Period and conduclion velocity of the striated muscle fibre. Acta physiol. scand. 1963. 59. 199–220. —Refractory period and conduction velocity of transmembrane potentials were determined in single frog muscle fibres by intracellular stimulation and recording at 14, 20 and 25° C. At the end of the absolutely refractory period the latency of the potential evoked by the second stimulus was substantially increased mainly due to a reduction in conduction velocity, delayed firing causing at most 10 per cent of the total delay. The absolutely refractory period terminated at the onset of the negative after potential, recovery in excitability, amplitude and conduction velocity in the relatively refractory period occurred within a time interval in which the membrane potential did not change more than about 3 mV. At 2–3 times the absolutely refractory period excitability and conduction velocity had a supernormal phase. At the absolutely refractory period the level of depolarization required to initiate a propagated response had increased from 40 to more than 60 mV (recorded 0.25–0.6 mm from the stimulating electrode). A local response appeared at a time interval of 70–80 per cent of the absolutely refractory period of the propagated response.
The Presence of Conjugated Adrenaline and Noradrenaline in Human Blood Plasma
Authors: Häggendal Jan
Published: December 2008

Häggendal, J. The presence of conjugated adrenaline and noradrenaline in human blood plasma. Acta physiol. scand. 1963. 59. 255–260. –The presence of conjugated adrenaline and noradrenaline in blood plasma is shown. As a rule 2 to 3 times more conjugated than free noradrenaline was found. When the free noradrenaline and adrenaline plasma levels were increased during muscular work and during insulin hypoglycemia, respectively, the levels of conjugated cate‐cholamines did not markedly change. After the oral administration of 5 mg adrenaline to a healthy man high amounts of conjugated adrenaline was found in the plasma and in the urine.
Handling of Glycerol in the Kidney
Authors: Kruhøffer Poul , Nissen Ole I.
Published: December 2008

Kruhøffer, P. and O. I. Nissen.Handling of glycerol in the kidney. Acta physiol. scand. 1963. 59. 284–294. —Essentially complete reabsorption of glycerol (and urine/plasma ratios below one) was observed in cats at low filtered loads. With increasing filtered loads the reabsorption rate continued to rise and the reabsorption fraction converged upon a value of about 0.4. The rate of metabolic conversion of glycerol in the kidneys – simultaneously determined from measurements of renal blood flow and arterio‐venous deficits –exceeded the reabsorption rate at low filtered loads whereas the relation was undoubtedly reversed at high filtered loads. Stop‐flow experiments indicated that the most distal parts of the nephron are sparsrly permeable to glycerol and that concentrations below that of arterial plasma may arise in proximal parts. The observations ma)‐ be accounted for on the assumptions that reabsorption at low filtered loads is predominantly a conversion reabsorption (diffusion from the tubular lumen into tubular cells maintained by a metabolic convcrsion inside the cytoplasm) and that at high filtered loads well above the level of saturation of the glycerol converting enzymes it is essentially due to transcellular back‐diffusion through the (proximal) tubular cells. I'he pattern of renal excretion of glycerol may thus be interpreted without resorting to special transmembranr transfer mechanisms.
Radiation Induced“Hypophysectomy” and Hypothalamic Lesions in Lactating Goats
Authors: Galel Charles C. , Larsson Wörje
Published: December 2008

Radiolesions were produced in the pituitary gland and/or median eminence‐pituitary stalk region of seven lactating goats by use of a narrow, collimated beam of 185 MeV protons from a synchrocyclotron. Radiation doses of 25 to 30 krad were restricted to these structures by rotation of the goats' heads around the vertical and horizontal axes of the planned lesion. Ten to 15 days after pituitary irradiation in four goats, milk production declined steeply over a ten‐day period to about 20 per cent pre‐lesion levels. In two of the“hypo‐physectdmized” animals with injury also in the median eminence, diabetes insipidus developed concurrently with the onset of lactation block. Daily replacement with prolactin (luteotrophin), somatotro‐phin, ACTH, triiodothyronine, and insulin had restored milk synthesis to 60 per cent of pre‐radiation levels when destruction of trigeminal nerve trunks by continued lateral spread of radiolesions caused an abrupt decline in the health of the goats.

In 3 lactating goats, irradiation of the median eminence/pituitary stalk region was followed after 25 to 30 days by (1) disappearance of the milk ejection reflex, (2) onset of diabetes insipidus characterized by absence of the normal interphase, (3) decline in milk production to 30 to 40 per cent of pre‐lesion levels, and (4) in one of them, marked loss of hair. That median eminence lesions blocked lactation secondary to pituitary insufficiency of ACTH, TSH, and STH, but not of prolactin or of oxytocin was suggested by the ability of varied therapeutic regimens to restore lactation.
Röntgenologische Bestimmung des Herzvolumens der Ratte
Authors: Tribukait Bernhard
Published: December 2008

A method for X‐ray determination of the heart volume of rats is described. Using general anesthesia the heart was X‐rayed in the frontal and sagittal planes. The relative volume of the heart, calculated from the length, breadth and depth was multiplied by the correction factor of 0.44 to obtain the absolute volume. The correction factor has been estimated by empirical analysis in heart models. The relationship between length (a), breadth (b) and the square of depth (c). i.e c2/a×b; does not change during growth. The standard error of estimate for a single determination calculated from 168 duplicated determinations was 7.3 %.
Cardiac Output in Healthy Subjects Determined with a CO2Rebreathing Method
Authors: Jernérus R. , Lundin G. , Thomson D.
Published: December 2008

The cardiac output is measured with a CO2rebreathing method suggested by Defares(1956). The mixed vmous CO2pressure is determined graphically from the breath by breath‐determined CO2content in a rubber bag during rebreathing from the bag. Arterial CO2pressure is assumed to be the same as in end‐tidal air. CO2eliminated per time unit is measured by collecting the expired air in a Douglas bag and the cardiac output is determined with the Fick equation. For the CO2analysis a rapid infrared CO2metcr is used. The obtained values at rest are of the same size as those obtaincd with the Crollman acetylene method. The values from the work cxperiments arc of the same magnitude as those obainted with dye‐diliution or direct Fick methods. Stroke volume shows increasr from rrst to work about 60–80 per cent.
The Effect of Cold Exposure on the Catecholamine Excretion of Adrenalectomized Rats Treated with Reserpine
Authors: Johnson G. E.
Published: December 2008

Adrenalectomizad rats subjected to moderate cold exposure showed a significant increase in noradrenaline excretion in urine. Adrenalectomized rats, treated with reserpine. howevar, failed to respond with an increase in the noradrenaline excretion during cold stress. A fall in the noradrenaline excretion of the reser‐pinized animals was usually followed by death. These results suggest that reserpine treatment inhibits the synthesis of noradrenaline in vivo and that the survival of moderately cold stressed adrenalectomized animals is related to the secretion of noradrenaline.
Effect of Adenine Nucleotides on Catecholamine Release and Uptake in Isolated Adrenergic Nerve Granules
Authors: Euler U. S. Von , Lishajko F.
Published: December 2008

On addition of 1–5 mM adenosine triphosphate (ATP) the spontaneous loss of noradrenaline from a suspension of adrenergic nerve granules is retarded or prevented. Adenosine diphosphate (ADP) exerts a similar effect while adenosine monophosphate (AMP) has little action. ADP and ATP also enhance the uptake of catecholamines from the incubation fluid. This effect is observed even with low amine concentrations in the incubation fluid in contrast to the uptake without addition of ATP. The ATP‐dependent uptake is inhibited by reserpine.
The Albumin Exchange in the Rabbit Eye
Authors: Bill Anders
Published: December 2008

Red cells labelled with Cr51 and albumin labelled with I131 were given i. v. to unanesthetized rabbits. Additional doses of I131‐albumin kept the plasma concentration of labelled albumin at a steady value. At different times after the first injection the animals were killed and the eyes dissected. The red cell contents of the choroid, the anterior uvea and the retina were the same at all time intervals, while the apparent volume of the plasma equivalent albumin space in the tissues increased with time. The results were analyzed in terms of intravascular and extravascular albumin compartments having the same concentration of I131‐albumin as plasma. The apparent volumes of the extravascular plasma albumin compartments were: in the choroid 112 μl per g tissue, in the anterior uvea 94 μl per g tissue and in the retina 4.8 μl per g tissue. The apparent turnover rates for the albumin solution in the extravascular albumin compartments were: in the choroid 0.0847 μl per min, in the anterior uvea 0.234 μl per min and in the retina 0.0075 μl per min. It was calculated that the albumin concentration in the tissue fluid of the choroid and in that of the anterior uvea as a whole is more than tenfold the albumin concentration in the aqueous humour and that the albumin drainage with the aqueous humour can account for less than 10 per cent of the albumin drainage from the eye.
The Uptake and Excretion of Ca47 in Normal and Rachitic Rats
Authors: Bohr Hans H.
Published: December 2008

Through measurements of the uptake and the excretion of radioactive calcium, Ca47, in normal and rachitic rats it is shown that the reduced retention of Ca47 in the rachitic rats corresponds to an increased excretion in the urine due mainly to a higher specific activity in the blood. In previously rachitic rats treated with vitamin D almost normal values for retention and excretion as well as for the specific activity in the blood are obtained.
The Effect of Pyridinium Aldoximes and Atropine on the Incorporation of DF32P in Rat Liver Cell Fractions
Authors: ÅGren G. , Ramachandran B. V.
Published: December 2008

The incorporation of radioactive diisopropyl phosphorofluoridate (DF32P) in the subcellular fractions of rat liver cells has been studied when injected alone or followed or preceded by pyridine‐2‐aldoxime methane sulphonate (P28), N,N'‐trimethylene‐bis‐(pyridinium‐4‐aldoxime) (TMB‐4) and atropine. In experiments with only DF32P the total labelled phosphorus (32P) incorporated in the liver as well as the amounts taken up in the microsomal and mitochondrial fractions attain a maximum value in 20 min, but there is a considerable readjustment of 32P between the nuclear and supernatant fractions even at 60 min. The oximes administered prophylactically or therapeutically affect both the rate of uptake of DF32P and the quantity incorporated. The effects are explained on the basis of the rate of penetration of DF32P in the cell and possible direct action of the oximes. Atropine has a high retarding effect on the uptake of DF32P in the liver, the total quantity incorporated being reduced to 5–10% of the control in some experiments.
Experiments on Nervous Factors Controlling Respiration and Circulation During Exercise Employing Blocking of the Blood Flow
Authors: Asmussen Erling , Nielsen Marius
Published: December 2008

During uninterrupted work on the bicycle ergometer the blood flow to the legs was suddenly interrupted by means of blood pressure cuffs. In the period with blocked circulation CO2 was added to the inspired air in such amounts that the alveolar PCO2 was maintained constant. The excess work O2‐uptake decreased up to 50%. The pulmonary ventilation, the pulse rate and the systolic blood pressure showed a steady and considerable increase. The cardiac output remained nearly constant with a tendency to decrease during the blocking period. The (a—v̄)O2‐difference and the mixed venous PCO2 consequently decreased considerably. These changes in respiratory and circulatory functions were well reproducible and the scattering of the values only small. It was concluded that the observed changes are neurogenic and caused by the increasing anaerobiosis in the blocked muscles. The nervous impulses involved may be elicited from muscle chemoreceptors, or they may stem from mechanoreceptors being activated through an observed recruitment of new motor units necessitated by the anaerobiosis.
Studies of the Relation Between the Frog's Electro‐Olfactogram (EOG) and Single Unit Activity in the Olfactory Bulb
Authors: Döving Kjell B.
Published: December 2008

The relationship between the frog's electro‐olfactogram (EOG) and the activity of single neurons in the olfactory bulb has been studied. In the absence of overt stimulation the units in the bulb exhibited a spontaneous activity with an average frequency of 0.7/sec. Butanol stimulation inhibited the activity of 65 per cent of the units investigated, 25 per cent were activated and 10 per cent reamined unaffected. Different types of odour gave different types of unitary response patterns. A standard odour mixture was more efficient in evoking inhibition than butanol alone. Some units were excited by low stimulus strength and inhibited by higher concentrations of odour. Units which were inhibited during odour stimulation frequently showed a post‐inhibitory excitation. The frequency of discharge of the activated units varied linearly with the amplitude of the EOG in the major part of the odour concentration range. The latency of the burst, measured from the start of the EOG, decreased from 400 to 100 msec with increasing stimulus strength. Adaptation was found to develop faster in the bulbar neurons than in the olfactory receptors.
Concentration of Lithium, Sodium and Potassium in Epithelial Cells of the Isolated Frog Skin during Active Transport of Lithium
Authors: Hansen H. Hvid , Zerahn K.
Published: December 2008

Abstract

The distribution of Li, K and Na in different layers of the skin of Rana temporaria was investigated after active transport of lithium. During the transport period the skin was short‐circuited, and after it had been sectioned in the frozen state, the slices were weighed and analyzed for Li, K and Na It was found that:

1. The concentration of Li was higher in the epithelial cells than in the outside solution for outside lithium concentrations of less than 10–20 mmole/1.

2. This may be explained by assuming the inside of the epithelial cells negative with respect to the outside solution, and assuming the potential to be dependent on the outside concentration of lithium.
Spontaneous Junctional Activity of Fast and Slow Parietal Muscle Fibres of the Hagfish
Authors: Alnæs Egil , Jansen Jan K. S. , Rudjord Torstein
Published: December 2008

The spatial distribution, amplitude distribution and interval distribution of spontaneous Junctional potentials of fast and slow muscle fibres of the myotomal parietal muscle of the hagfish have been studied. The fast muscle fibres are focally innervated with an end‐plate area localized to one end of the fibre whereas the synaptic regions of the slow muscle fibres are distributed along their entire length. The mean distance between the synaptic sites of the slow muscle fibres is less than 0.1 mm. The electrical cable constants of the two types of fibre have been determined by passing square waves of current through the membrane and recording the changes in membrane potential. The specific resistance of the membrane of the slow fibres is unusually high.
The Effect of Heparin and ε‐Aminocaproic Acid on the Coagulation in Hypothermic Dogs
Authors: Johansson Bengt W. , Nilsson Inga Marie
Published: December 2008

Coagulation studies were performed in 15 dogs subjected to cooling to 20° C under various conditions. Thrombocytopenia invariably occurred during the cooling process. Hypothermia alone was followed by decrease of fibrinogen and prothrombin and factor VII and by an increased fibrinolytic activity and antithrombin activity. Hyperactive factor V levels were recorded during hypothermia and the plasma also showed thromboplastic activity. Administration of e‐ACA to the dogs before and during the hypothermia prevented the development of fibrinolytic activity but it did not prevent the decrease of fibrinogen and prothrombin and factor VII. Hyperactive factor V levels were recorded during the cooling as well as a marked thromboplastic activity in the plasma. Administration of heparin to the dogs before and during the hypothermia prevented the decrease of fibrinogen. The fibrinolytic activity was not prevented. No hyperactive factor V levels occurred. Simultaneous administration of heparin and e‐ACA to the hypothermic dogs prevented both the decrease of fibrinogen and the fibrinolytic activity.

It is concluded that the coagulation defects induced by hypothermia are due mainly to intravascular coagulation. The decrease of fibrinogen which takes place in connection with hypothermia is due to its consumption in the coagulation process and not caused by the fibrinolytic process. It appears unwise to use ε‐ACA alone during hypothermia.
Accumulation of Fluid in Exercising Skeletal Muscle
Authors: Jacobsson S. , Kjellmer I.
Published: December 2008

Lymph flow from, and volume changes in, muscles during exercise were recorded simultaneously. During exercise there occurs an outward filtration at an initially steady rate. This filtration gradually diminishes and finally ceases. Under the experimental conditions used lymph flow was very small compared with the rate of outward filtration. The capillary filtrate accumulated in the muscle. The amount of fluid accumulated varied with the work load. The factors limiting outward filtration are discussed. The most important limiting factors seem to be gradually rising tissue pressure, and to some extent changes in colloid osmotic pressure on either side of the capillary wall.
Contraction Properties of Intrinsic Laryngeal Muscles
Authors: Mårtensson A. , Skoglund C. R.
Published: December 2008

The contraction times of laryngeal muscles in the dog were found to differ from 14 and 16 msec for the thyroarytenoid and lateral cricoarytenoid muscles to 30 and 35 msec for the posterior cricoarytenoid and the cricothyroid muscles respectively. The same relation between the contraction times of fast and slow muscles was characteristic also of some other species investigated. The view is advanced that the short contraction time of the two sphincter girdle muscles primarily serves the purpose of closing the laryngeal aperture in protective larynx reflexes.

The thyroarytenoid and cricothyroid muscles of dog, chosen as representatives of fast and slow muscle, were subjected to a more detailed analysis. Determinations of the active state plateau by the method of superimposition of tension curves from one and two stimuli gave values of 3.0–4.0 msec for the thyroarytenoid and 3.5–4.5 msec for the cricothyroid muscle. After determinations of the tetanus‐twitch ratios for the two muscles, the rate of decay of the active state could be estimated and was shown to be faster in the thyroarytenoid muscle. Tetanic direct stimulation showed that complete fusion may not occur until above 300 per sec in the cricothyroid and above 400 in the thyroarytenoid muscle.

Analogous analyses performed by indirect stimulation of the fast and slow muscle gave very similar results with respect to mechanical separation time and fusion frequency. The results from an action potential analysis during short‐interval nerve stimulation are discussed from the point of view of the active state conception.
The Ascending Projections of Trigeminal Neurones in the Cat, Investigated by Antidromic Stimulation
Authors: Eisenman J. , Fromm G. , Landgren S. , Novin D.
Published: December 2008

Cats anaesthetized with nembutal were used. Antidromic responses were evoked in single trigeminal neurones by electrical stimulation of the contralateral trigeminal lemniscus (COTL) or the ipsilateral dorsal ascending trigeminal tract (IPDT) at the mesencephalic level. The neurones were localized to the main sensory nucleus (NVsnpr) or the rostral subdivision of the nucleus of the spinal trigeminal tract (NVspoγ) and classified in groups as described by Eisenman, Landgren and Novin (1963).

An antidromic response was recorded from 48 per cent of the cells located in NVsnpr and classified as touch cells with small receptive fields or as whisker cells. The corresponding percentage for NVspoγ was 36. Gordon, Landgren and Seed (1961) found that 40 per cent of a similiar group of cells located in the caudal part of the nucleus of the spinal trigeminal tract was antidromically discharged from COTL. It may therefore be concluded that secondary tactile cells sending their axons into the ascending trigeminal paths are about equally common in the three parts of the trigeminal nucleus so far investigated.

It was further observed, that secondary touch cells with small oral receptive fields, and located in the dorsomedial part of NVsnpr, sent their axons into IPDT, whereas secondary touch cells with small perioral or periorbital receptive fields, and located in the lateral and ventrolateral parts of NVsnpr or NVspoγ, projected into COTL. About 25 per cent of the trigeminal cells responding to nociceptive stimuli from large receptive fields were fired antidromically from COTL. In some trigeminal cells an antidromic response was evoked from the region of the red nucleus.
Disclosure of Labile Monoamine Fractions in Brain and Their Correlation to Behaviour
Authors: Häggendal Jan , Lindqvist Margit
Published: December 2008

The recovery rates of brain monoainines after disruption of long‐term treatment of rabbits with reserpine (0.2 mg/kg/day) and after single doses of the drug (0.2 and 1.0 mg/kg) have been compared. No clearcut difference in recovery rates between the two types of treatment could be detected. In both cases normal values were reached only after several weeks. From the 3rd to 4th day the animals showed a normal gross behaviour in spite of low monoamine levels. Brain monoamines and behaviour were studied in chronically treated rabbits during the 24 hours following the daily injection. A temporal correlation between the changes in the remaining low monoamine levels and behaviour was demonstrated, which is in contrast to observations made in animals receiving a single dose for the first time. It appears that chronic reserpine treatment results in removal of large physiologically inert monoamine fractions, thus disclosing small, labile, functionally essential fractions.
The Digestion and Absorption of Lactose by the Intact Rat
Authors: Dahlqvist A. , Thomson D. L.
Published: December 2008

The digestion and absorption of 2 different doses of lactose was compared with that of equivalent amounts of glucose and galactose. The sugars were administered intragastrically together with a water‐soluble, non‐absorbable marker, polyethylene glycol, in order to study the rate of movement of the sugars through the gastrointestinal tract and to determine their site of absorption. Only the larger dose of lactose showed an effect on the rate of transit of the sugars, and this effect was confined to the distal third of the small intestine. When the monosaccharides were fed, they were almost completely absorbed in the upper two‐thirds of the small intestine, glucose being absorbed more rapidly than galactose. Lactose was absorbed in all parts of the small bowel, and, after the larger dose, as much as 25% of the amount of sugar fed was absorbed from the colon. Large amounts of sugar were found in the distal small intestine and colon as long as 6 hours after lactose administration. The ceacal contents contain large amounts of lactase, a considerable fraction of which is enzymatically different from small‐intestinal mucosal lactase. This caecal lactase is probably of bacterial origin. In the small intestine, the rate of hydrolysis of lactose was rate‐limiting for its absorption. In the large bowel, lactose was hydrolysed more rapidly than the monosaccharides could be absorbed.
Further Studies on the Action of Thyroid Hormones on the Metabolism of Collagen
Authors: Kivirikko Kari I. , Koivusalo Martti , Laitinen Ossi
Published: December 2008

In experiments on rats, the effects of triiodo‐L‐thyronine and of hypothyroidism induced either by propylthiouracil or 131I on the urinary excretion of hydroxyproline were studied. Further, the content of 0.45 M NaCl‐soluble collagen hydroxyproline in the skin was determined in the experiment on hypothyroidism. In experiments with chick embryos the effect of the propylthiouracil treatment on free hydroxyproline and 1 M NaCl‐soluble collagen hydroxyproline was studied. The amounts of both free and total hydroxyproline excreted in the urine of rats increased after the administration of triiodo‐L‐thyronine and decreased greatly after the administration of propylthiouracil or 181I. In the skin of rats given 131I or propylthiouracil the content of 0.45 M NaCl‐soluble collagen hydroxyproline diminished but the decrease after propylthiouracil was not statistically significant. In chick embryos the relative amounts of free hydroxyproline and of 1 M NaCl‐soluble collagen hydroxyproline, expressed as a percentage of the total hydroxyproline, and the total amounts of hydroxyproline per embryo were lower in the propylthiouracil‐treated embryos than in the controls.
Inhibition of Gastric Acid Response to Sham Feeding in Pavlov Pouch Dogs by Acidification of Antrum
Authors: Anderson Sven , Olbe Lars
Published: December 2008

The nervous phase of gastric acid secretion was studied on sham fed Pavlov pouch dogs with an isolated, innervated antrum. The sham feeding response was not inhibited by antral acidification to pH > 2.5. A slight but highly significant inhibition occurred at antral pH 2 and a substantial inhibition at antral pH 1–1.5. The results suggest that on vagal stimulation gastrin is released from the antrum at antral pH ≤ 2 in amounts sufficient to augment significantly the nervous secretory response. Inhibition of the sham feeding response by antral acidification was eliminated by a very low submaximal dose of intravenously administered gastrin in accordance with the hypothesis that depression of vagal release of gastrin is the main inhibitory mechanism elicited by antral acidification during the nervous phase of gastric acid secretion.
Histochemical and Biochemical Observations on the Effect of Reserpine on Noradrenaline Storage in Vasoconstrictor Nerves
Authors: Fuxe Kjell , Sedvall Göran
Published: December 2008

Tissue sections of cat skeletal muscle were analysed for adrenergic fibres by a specific histochemical fluorescence technique. Fibres with green fluorescence and varicosities typical of adrenergic fibres were seen almost exclusively surrounding the external muscular layer of the small arteries in the tissue. No adrenergic nerve fibres could be detected after postganglionic sympathetic denervation of the muscles. Reserpine (5 mg/kg i.v.) caused a complete disappearance of the fluorescence of the fibres within a few hours after administration. Decentralization of the sympathetic nerves to the muscles prevented the fibres from losing fluorescence after reserpine. An infusion of noradrenaline 24 hours after reserpine administration caused a reappearance of fluorescent nerve fibres of practically normal appearance. A certain amount of noradrenaline could be detected by biochemical assay both in decentralized muscles 5 to 9 hours after reserpine administration and in muscles from reserpine‐treated animals in which noradrenaline had been infused. The data support the view that a small amount of noradrenaline can be retained in adrenergic nerves by mechanisms which are resistant to the effect of reserpine.
Influence of Nethalide on the Phosphorylase Activating Effects of Adrenaline and Isoprenaline in Experiments on Isolated Rat Diaphragm
Authors: Mohme‐Lundholm Ella , Svedmyr Nils
Published: December 2008

Nethalide at a concentration of 10‐4totally inhibited the phosphorylase‐activating effect of L‐adrenaline or L‐isoprenaline at a concentration of 10‐5in experiments on isolated rat diaphragm.
Observations on Antigen‐Induced Histamine Release from Rabbit Skin
Authors: Westerholm Barbro
Published: December 2008

Antigen, 1 mg/ml, caused low but significant histamine release from chopped abdominal skin of rabbit. Release was dependent upon pH and temperature. Certain enzyme inhibitors such as allicin (SH group inhibitor) and ninhydrin (NH2, group inhibitor) blocked release. Reduced glutathione reversed the inhibitory action of allicin. Dinitrophenol and anoxia inhibited release only in glucose‐free medium. The results suggest that in rabbit the antigen‐induced histamine release from skin follows a similar pathway to that of the anaphylactic histamine release from rat and guinea‐pig tissues and occurs after activation of a process requiring energy from oxidative or glycolytic processes.
Effect of Histamine and Insulin on Eosinophils and Mast Cells in the Rat Gastric Mucosa1
Authors: Räsänen Toimi
Published: December 2008

The number of mast cells in the mucosa of the glandular stomach of the rat decreased on account of degranulation 2–4 hours after histamine and insulin injections and after ingestion of food. Re‐granulation of the mast cells occurred in a later phase. Morphological changes were established in the mast cell granules during gastric stimulation. Tissue eosinophilia of the lamina propria of the glandular stomach increased at the beginning of the stimulation, decreasing in a later phase. Lethal insulin shock caused an increase in the tissue eosinophilia of the glandular stomach. The role of the heparin and histamine contained in the mucosal mast cell granules during the stimulation of the gastric mucosa, in the phase in which the ion changes and local heparinemia in the mucosal lamina propria perhaps provoke inhibition of eosinolysis, is suggested.
An Occlusive Mechanism in the Fallopian Tube of the Rabbit
Authors: Brundin Jan
Published: December 2008

The study was undertaken'to determine whether a preovulatory occlusive mechanism in the isthmus of the rabbit Fallopian tube separates the cavity of the ampule from that of the uterus, as is the case after ovulation. An in vitro method for the recording of the intraluminal pressure variations of the isolated rabbit Fallopian tube has been used and is described. Evidence for the existence of an active occlusive mechanism in the isthmus of the estrous rabbit Fallopian tube is presented and discussed. There is a difference in the sensitivity of the Fallopian tube and the uterine horn to noradrenaline and acetylcholine. The ampullary region is more sensitive to acetylcholine than is the uterine horn, which is more sensitive to noradrenaline than the ampulla.
Effect of Vagotomy, Vagus Stimulation and Various Drugs on the Substance P Content in the Small Intestine of the Rabbit
Authors: Radmanovic B.
Published: December 2008

Cervical vagotomy significantly increased the Substance P (SP) content in the rabbit's small intestine, from 2.8 ± 0.2 U/g to 7.2 ± 0.6 U/g. Stimulation of either right or left vagus in the neck significantly decreased SP in the same tissue from 2.8 ± 0.2 to 1.0 ± 0.2 U/g. The SP values increased 15 min after cessation of stimulation and reached control values within 30 min. Physostigmine significantly decreased the SP content in the rabbit's intestine to 1.7 ± 0.2 U/g; while no definite effect was observed after administration of hexamethonium, chlorisondamine, atropine, reserpine, chlorpromazine, p‐hydroxymercuribenzoate or nicotine. It is suggested that vagus stimulation and physostigmine deplete the SP stores in some peripheral nervous structures in the intestine. Conversely, vagus section may allow a replenishing of the stores.
Capillary Permeability in Skeletal Muscle during Rest and Activity
Authors: Arturson G. , Kjellmer I.
Published: December 2008

In exercising skeletal muscle fluid is filtered from the blood stream to the interstitial space. The filtration process is facilitated by an increase of the capillary filtration coefficient. This coefficient is dependent upon capillary surface area and capillary permeability. The present study was designed to ascertain whether the capillary permeability increases in exercising muscle. The permeability of the capillary membrane was studied in two dogs. Dextran of different molecular sizes was injected intravenously, after which the concentration of the dextran in pure muscle lymph was compared with that in arterial plasma. The ratio between these concentrations did not change significantly when exercise was simulated by repeated stimulation of the motor nerve. It is therefore concluded that capillary permeability does not change during muscular exercise.
Cyclic Variation in the Body Temperature of the Male Rabbit
Authors: Degerman G. , Kihlström J. E.
Published: December 2008

Daily recordings of body temperature in male rabbits have been shown to vary cyclically. The mean length of these cycles is very close to that of the cyclic variations in the sexual functions of the male rabbit previously found. Further the coincidence in phase between the cycles of the body temperature and those of the seminal volumes is statistically significant.
Comparative Investigation of the Calorigenic and Lactic Acid Stimulating Effects of Isoprenaline and Adrenaline in Experiments on Rabbits
Authors: Lundholm Lennart , Svedmyr Nils
Published: December 2008

The stimulating effects of DL‐isoprenaline and L‐adrenaline on oxygen consumption and lactic acid production were compared in experiments on rabbits. In doses which produced a submaximal response DL‐isoprenaline was, for both effects, 4–5 times as potent a stimulant as L‐adrenaline. Although the calorigenic action of isoprenaline was largely referable to increased lactic acid oxidation, the fact that isoprenaline, in the doses tested, markedly stimulated the heart rate suggests that an increased cardiac activity contributed to the calorigenic effect. Intra‐arterial infusion of isoprenaline into the brachial artery increased the elimination of lactic acid from skeletal muscle while commensurately augmenting the blood flow. It seems probable that the vasodilator effect of isoprenaline in the rabbit stemmed, at least in part, from increased lactic acid production in the skeletal muscle. — The relations for doses of L‐isoprenaline, L‐adrenaline and L‐noradrenaline which produced equal lactic acid producing and calorigenic effects in the rabbit were 1: 9: 120.
Uterine Motility of the Estrogenized Rabbit
Authors: Setekleiv Johannes
Published: December 2008

The myometrial response to rapid distension consists of a quick contraction, the early stretch response, followed by an increase in the rhythmic activity. The latency and amplitude of the early contraction has been studied during increasing degrees of distension and during repetitive distensions. The frequency of the rhythmic contractions increases with increasing distension; the amplitude and the external work performed by each contraction at first increases and later decreases. Data obtained from isometric and isotonic recordings indicate that the pacemaker activity is not directly related either to the intra‐uterine volume or to the intra‐uterine pressure but rather to the tension in the myometrial cells. The independency with which the two horns respond to distension, the lack of effect of local and spinal anesthesia and of autonomic blocking agents indicates that the active response to distension is of myogenic origin. The intra‐uterine pressure is not maintained during constant distensicn but decreases at first rapidly, later more slowly.
Uterine Motility of the Estrogenized Rabbit
Authors: Setekleiv Johannes
Published: December 2008

The amplitude of the uterine contraction elicited by a few seconds stimulation of the hypogastric nerve depends on: (1) the stimulus frequency. the contraction being maximal at 30 to 50 cps; (2) the excitability of the myometrium, being increased in a period from 20 to 60 sec following a preceding stimulus, and; (3) the degree of uterine distension. Whereas stimulation for a few seconds elicits a single contraction, prolonged stimulation (for several minutes) at low frequencies (5–10 cps) evokes a series of rhythmic contractions. Prolonged stimulation at frequencies above 10 cps causes in addition a transient elevation of the minimum pressure. I. v. administration of cocaine does not potentiate the response to hypogastric nerve stimulation, whereas potentiation by cocaine is obtained when the agent are applied intra‐uterinely. This effect, as well as the response to adrenergic blocking agents, indicate the presence of adrenergic fibres in the hypogastric nerve supplying the myometrium. Evidence for cholinergic fibres to uterus in the hypogastric nerve was not obtained. The uterine response to splanchnic nerve stimulation differs from the response to hypogastric nerve stimulation by a longer latency and by a more gradual onset.
Effect of Ethionine on the Incorporation of Palmitic Acid‐1‐C14 into Rat Serum Lipoproteins
Authors: Karvinen Esko , Koskimies Olli , Miettinen Matti
Published: December 2008

Ethionine administration to female rats had no significant effect on the radioactivity of the serum chylomicron fraction after ingestion of palmitic acid‐1‐C14. On the other hand, ethionine administration resulted in a decrease in the incorporation of palmic‐acid‐1‐C14 into the serum albumin plus α1lipoprotein fraction and into the α2lipoprotein fraction. There was no significant difference in the activity of the serum β lipoprotein fraction between the ethionine and control rats. Total liver fat and the total amount of palmitic acid‐1‐C14 incorporated in the liver fat were significantly higher in the ethionine treated animals than in the saline controls. However, the relative specific activity of the liver fat of the ethionine treated group was lower than that of the controls.
Studies on Heart Lymph
Authors: Areskog N.‐H. , Arturson G. , Grotte G.
Published: December 2008

Areskog, N.‐H., G. Arturson and G. Grotte. Studies on heart lymph. I. Kinetics of 131I‐albumin in dog heart‐lung Preparations. Acta physiol. scand. 1964. 62.209–217. — The transport of 131I‐albumin from plasma to lymph was studied in dog heart‐lung preparations. Cannulation of a lymph vessel mainly draining the left ventricle was performed. After injection of the labelled substance, plasma mixing was complete within a few minutes. The plasma concentration of the tracer was constant for 2–3 hours. During this time plasma and heart‐lymph samples were collected. The increase in the concentration of the labelled substance in heart‐lymph showed a time course indicating that the substance from the intra‐vascular compartment was mainly distributed to a single extra‐vascular compartment. The data could thus be fully explained by a two‐compartment model and the permeability constants and the size of the extra‐vascular albumin space drained by the lymphatic canola could be calculated.

The present experimental approach therefore allowed a “quantitative lymph experiment”, i. e. the size of the extra‐vascular albumin space drained by a lymphatic cannula could be defined and also an idea of the amount of albumin filtered across the capillary walls and the rate of removal of albumin from the extra‐vascular space via the lymphatics was obtained.
Exchange of I131‐Albumin in Acute Inflammatory Oedema
Authors: Hvidberg Eigill , Langgård Hans , Schou Jens , Szporny Laszlo
Published: December 2008

The shift of protein between plasma and experimentally induced inflammatory oedema has been studied in mice after intravenous injection of radioiodinated human serum albumin. Calculations were based on the difference between the total amounts or radioactivity in inflamed skin samples and self control samples of equal surface areas. It was demonstrated that during the initial 15 min of the inflammatory process the oedema contained less radioactivity per unit weight than the plasma. Subsequent to this point, however, the activity increments of the inflamed tissue could be accounted for in terms of extravasated plasma. It was further shown that human serum albumin injected intravenously to mice disappears from the plasma according to a linear function in a semilogarithmic system. The disappearance half time was 99 min in control animals but 32 min in mice with localized inflammatory oedema. The average plasma volume of mice weighing 25 g was 1,1 ml as determined by means of radioiodinated human serum albumin.
Uterine Motility of the Estrogenized Rabbit
Authors: Setekleiv Johannes
Published: December 2008

Uterine contractions were elicited by electrical stimulation of points located in the lateral part of the medulla oblongata, whereas inhibitory responses were induced from the midline medullary region. Cerebellar stimulation determined an inhibition of the rhythmic uterine activity followed by a rebound effect, on cessation of the stimulation. From the hypothalamus three different responses were obtained: (i) excitatory effects from the perifornical, the dorsal, lateral and posterior hypothalamic areas due to sympathetic ac‐rivation, (ii) uterine excitation by oxytocin liberation induced from the ventromedial part of the hypothalamus, and (iii) inhibition of the uterine rhythmic activity by stimulation of a restricted region in the lateral hypothalamic area. Excitatory responses were also evoked from the amygdala, from sensorimotor cortex, and the anterior limbic region. Inhibitory uterine tesponses were produced from the two cortical areas just mentioned as well as from the orbital surface.
Der Effekt plethysmografischer Fullungsdrucke bis 20 cm H2O auf die lokale Extremitätendurchblutung
Authors: Graf Klaus , Rosell Sune
Published: December 2008

The local circulatory effects of the pressure in flexible air‐filled segmental plethysmographs applied to the human forearm and the hind leg of the cat were investigated. The rate of arterial inflow was measured both by means of a plethysmograph and by either thermal conductivity recorders or a drop recorder. The forearm blood volume capacity was measured. Pressures in the plethysmograph less than 5 cm H2O did not affect the circulation. In the forearm, pressures in the plethysmograph of 10 and 20 cm H2O caused partial venous occlusion and thereby reduced the local vascular capacity by about 10–15 and 30–35 per cent respectively. Raising the plethysmograph pressure from 5 to 10 cm H2O did not influence the arterial inflow rate or produced a slight increase. However, after deep forearm nerve blockade a decrease of arterial inflow rate was produced. At pressures in the plethysmograph higher than 10–15 cm H2O a reduction of the arterial inflow in the forearm usually occurred, and was probably more pronounced in the vessels of the skin than those of the deeper tissues. The local effects on arterial inflow of plethysmograph filling pressures higher than 5 cm H2O may therefore consist of a simultaneous tendency to mechanical obstruction of outflow (“passive” component) and a counteracting vasodilatation of the resistance vessels (“reactive” component) which compensates or overcompensates within a certain range for the increasing filling pressure.
Reabsorption of Inorganic Sulfate by the Renal Tubules of the Rat
Authors: Berglund Fredrik
Published: December 2008

Reabsorption of inorganic sulfate by the renal tubules was measured in the rat by means of a constant infusion technique. Plasma sulfate concentration was varied between 1.1 and 4.6μmole/ml. When glomerular filtration rate was measured by inulin clearance there seemed to be reabsorption at low sulfate levels but secretion at higher levels. When polyethylene glycol of molecular weight 1,000 or 400 was used instead of inulin, the calculated values for glomerular filtration rate were almost twice as high, and reabsorption of filtered sulfate exhibited a Tm (transfer maximum) of 1.02μmole/ml glomerular filtrate. The Tm is of the same order of magnitude as in the dog (1.65μmole/ml glomerular filtrate) and man (0.97μmole/ml glomerular filtrate). Carinamide had no effect, indicating that tubular secretion of sulfate is absent or insignificant. Neither did phlorizin have any effect, contrary to expectations from earlier experiments on the intact dog and on kidney cortex slices of the rat.
The Tissue Distribution and Metabolism in the Rat of Intravenously Injected Labeled Fat Emulsions
Authors: Belfraoe Per , Edgren Bo , Olivecrona Thomas
Published: December 2008

An artificial fat emulsion containing H3‐palmitic acid labeled triglycerides was injected intravenously into rigorously carbohydrate‐fed rats. One group was given a small dose (5.6 mg lipid), and another group a large dose (136 mg lipid). Radioactivity in blood and tissue lipids was studied at a series of time intervals. The label disappeared rapidly from the circulating blood and most of it was taken up by the liver and the spleen. The hepatic uptake of radioactivity showed an inverse relationship to dosage, while the reverse was true for the splenic uptake. In both instances hepatic and splenic uptake was greater than in previous experiments using labeled chylomicrons. The label taken up by the liver was first present almost exclusively in the non‐phospholipid fraction, but subsequently label appeared in the liver phospholipids.

In a second experiment an artificial soybean emulsion containing tracer amounts of G14‐glycerol‐H3‐palmitic acid labeled triglycerides was injected into rigorously carbohydrate‐fed rats. In this experiment only the ratios C14/H3 in the tissue lipids were studied. The data indicated that the fat emulsion triglyceride was taken up without prior hydrolysis into the liver and spleen.
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

Perfusion 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.