bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of CO2 and Hydrogen Ions on Active Na Transport in the Isolated Frog Skin
Authors: Funder Jørgen , Ussing H. H. , Wieth J. O.
Published: December 2008

The effect of pH on the active sodium transport of the isolated frog skin has been investigated. The sodium transport has previously been considered to be particularly sensitive to lowering of pH in the solution bathing the corium side of skin. However, when pH was lowered by unilateral titration with carbon dioxide, the active sodium transport was more sensitive to changes of pH on the epidermal side than on the corium side of the skin. Raising bicarbonate concentration from 2.4 to 57.5 or 115 mM increased the tolerance to carbon dioxide. This effect of bicarbonate was exerted from the corium side of the skin. The differing respones seen in the presence of 2.4, 57.5, and 115 mM bicarbonate showed no direct correlation to pH of the media. When phosphate concentration was below 1 mM, lowering of pH to values between 6.5 and 5.8 with HCI or H3 PO4 in the medium on the corium side had only slight effect on the sodium transport. At phosphate concentrations of 5—6 mM the transport was found to be inhibited rapidly. The results suggest that the active sodium transport of the isolated frog skin is affected by condition lowering the intracellular pH of the transporting cells.
About Arterio‐venous Shunts in Salivary Glands
Authors: Häggendal Egil , Sivertsson Ramon
Published: December 2008

In 5 animals the krypton (Kr85) elimination rate from the exposed submaxillary gland was studied. Both local and intra‐arterial administration of the indicator isotope was used before, during and after chorda stimulation. The results demonstrate a tenfold increase in tissue blood flow during chorda stimulation and strongly suggest that this increased flow passes through capillaries, with no signs of any opening of arterio‐venous shunts.
Acid‐Base Relations in Arterial Blood and Cerebrospinal Fluid of the Unanesthetized Rat
Authors: Pontén Urban , Siesjö Bo K.
Published: December 2008

A technique is described for collection of arterial blood in unanesthetized rats and for removal of cisternal cerebrospinal fluid (CSF) after anesthesia in such a way that the acid‐base parameters can be considered to reopresent the unanesthetized state. In uninjected rats the plasma pH was found to be 7.47, the pCO2 38.5 mm Hg and the plasma bicarbonate concentration 27.3 meq/1. When such rats were made acidotic or alkalotic by means of intraperitoneal injections of acid and basic solutions both the CSF bicarbonate concetration, and the CO2 tension, varied linearily with the plasma bicarbonate concentration, but the changes in the CSF bicarrbonate concentrtion were only 35 per cent of the corresponding plasma changes. There were small but significant changes (0.04 pH units) of the CSF pH in the same direction as in blood and there was thus no indication of paradoxical shifts in the CSF pH. The implication of these findings for current theories regarding the regulation of respiration is discussed.
Trapping of Sodium, Potassium, Sucrose, and Albumin in the Packed Cell Column of the Hematocrit
Authors: Funder Jørgen , Wieth Jens Otto
Published: December 2008

The observation of Maizels and Remington (1959) that high molecular markers are trapped to a significantly lower degree between centrifuged red cells (RBC) than small sized molecules, has prompted a study of the trapping of 131I‐labelled albumin, sucrose‐14C, 22Na and 42K. Albumin was found to be trapped to a significantly lower degree than sodium. The difference between trapping of 22Na and of 131I‐labelled albumin at 0d̀ C averaged 1.8 per cent, independent of the force and duration of centrifugation. Removal of membrane neuraminic acid had only a slight effect on trapping of albumin. The percentual trapping of 22Na and of 42K was found to equal trapping of sucrose‐14C, when the rate of Na and K uptake into RBC at 0d̀ C was considered. These rates of sodium and potassium influx at normal extracellular concentrations were 0.24 and 0.027 meq kg RBC‐1 h‐1. Based on the experimental findings the existence of a truly intracellular, rapidly exchangeable fraction of RBC sodium is rejected.
Reuptake and Net Uptake of Noradrenaline in Adrenergic Nerve Granules with a Note on the Affinity for l‐ and d‐Isomers
Authors: Euler U. S. von , Lishajko F.
Published: December 2008

The net loss of noradrenaline (NA) from bovine splenic nerve granules observed after incubation for 60 min at 20d̀ C in phosphate buffer is reduced in the presence of NA in the incubation medium. The effect is observed from 10‐7M NA and gradually increases so that at 10‐4M NA in the medium the net loss is small. By continuous removal of the NA in the medium by addition of potassium ferricyanide, the net loss reaches a maximum value which may represent the basic release rate. The effect of NA in the medium is due to reuptake of NA as indicated by the incorporation of dI‐3H‐NA in the granules during incubation. Preliminary observations suggest that the reuptake is also ATP‐dependent. During successive depletion of labelled stores at 20d̀, the specific activity of NA is unalterec indicating a uniformly labelled pool. In partially NA depleted nerve granules the net uptake of NA from the medium is enhanced by ATP‐Mg2and dependent on the NA concentration in the medium. A method for estimating the relative affinity of the l‐ and d‐isomer for nerve granules is described. The mean value found for the affinity ratio l‐NA/d‐NA was 9.4 (range 4.2–15.7). It is suggested that the continuous turnover of NA in the nerve storage granules is of major significance for the physiological transmitter homeostasis.
Inhibition of Salivary Secretion and Secretory Potentials by g‐Strophantin, Dinitrophenol and Cyanide
Authors: Petersen Ole Holger , Poulsen Jørgen Hedemark
Published: December 2008

The hyperpolarization of the contraluminal acinar cell membrane which takes places when the submandibular gland is stimulated, is called the secretory potential. Much indirect evidence has been presented in favour of the hypothesis that the mechanism of establishment of this potential is due to an active electrogenic chloride transport, and not to a change of the membrane permeability for ions. This transport should be responsible for the formation of the saliva. If this is true, both secretory potentials and secretion should be inhibited to the same degree by metabolic inhibitors. In the present work it was found that the metabolic inhibitors dinitrophenol and cyanide and the cardiac glucoside g‐strophantin (ouabain) had the ability to inhibit completely both secretion and secretory potentials in the perfused cat submandibular gland.
The Relationship between Active Constriction and Passive Recoil of the Veins at Various Distending Pressures
Authors: ÖBerg Bengt
Published: December 2008

The vasoconstrictor fibre influence on veins, exposed to varying distending pressures, was analysed with respect to the relative contribution of active venoconstruction and passive venous recoil, respectively, to total venous blood mobilization. The results indicate that active venoconstriction can produce only a minor reduction of venous capacity when venous transmural pressure is low but a considerable diminution of the capacity at higher venous pressures, provided the pressure is not so high as to “overstretch” the muscle elements. — The passive emptying of blood at vasoconstrictor fibre stimulation is very pronounced in the low pressure range, but becomes small at higher pressures, in accordance with the pressure‐volume characteristics of the veins, demonstrating an apparently very high distensibility at low pressures. This high “distensibility” is mainly due to changes of vessel geometry, associated with the collapse, and does not reflect true wall distensibility. … Consequently, when venous pressure is low, venous function is primarily governed by passive factors, while active shortening of venous smooth muscles will play a dominant role first when the vessels are kept well distended. — The implications of these findings for venous control is discussed, with special respect to man, where venous pressure varies greatly with body position. Some methods earlier used for assessing venous tone changes are critically analysed.
The Efects of Compound 48/80 and Distilled Water on the Adenosine Triphosphate Content of Isolate Rat Mast Cells
Authors: Diamant Bertil
Published: December 2008

The ATP content of isolated pritoneal mast cells from 15 rats averaged 1.7 ± 0.1 mmoles/kg dry weight. When degranulation of the cells and histamine release was induced by compound 48/80 no significant decrease in the ATP content could be demonstratred. When buffered distilled water was used instead as degranulating and histamine releasing agent the ATP content of the cells decreased by 65—75 per cent with an apparent t1/2 of about 20 sec. The result are descussed in relation to the postulated energy‐dependent reaction involved in the degranulation by compound 48/80.
Influence of Vasoconstrictor Nerve Activity on the Cholinergic Vasodilator Response in Skeletal Muscle in the Dog
Authors: Bolme Per , Ngai S. H. , Rosell Sune
Published: December 2008

The cholinergic sympathetic vasodilator nerves were activated by topical stimulation in the hypothalamus and the mesencephalon during graded levels of vasoconstrictor nerve activity. Chloralose anestletized as well as conscious dogs were used. In the anesthetized dogs the isolated gracilis muscle was perfused with blood at a constant flow rate. The perfusion pressure was recorded. In unanesthetized dogs blood flow was measured with an electromagnetic flow‐meter probe placed around the external iliac artery. Increase in vasoconstrictor nerve activity was produced either by clamping one or both common carotid arteries or by central topical stimulation through electrodes in the vasoconstrictor areas in the hypothalamus. Activation of cholinergic vasodilator nerves produced a vasodilator response in the skeletal muscles. An increase in vasoconstrictor tone inhibited the effect of threshold vasodilator nerve stimulation. However, when the vasodilator nerves were stimulated with suprathreshold intensity the vasodilator response could be produced even at an elevated vasoconstrictor tone. On the other hand a very pronounced vasoconstrictor tone, only possible to produce in the anesthetized dogs, reduced the vasodilator response in some experiments. The experimental findings indicate a peripheral antagonism between the two types of vasomotor nerves, however, at least in dogs this is presumably of minor physiological importance. A strong activation of cholinergic vasodilator nerves may increase the muscle blood flow even if the arterioles are under increased vasoconstrictor nerve activity.
Reduction of Antral and Duodenal Gastrin Activity by electrical Vagal Stimulation1
Authors: Fyrö Bengt
Published: December 2008

The effect of electrical vegal stimulation on the antral and duodenal gastrin activity was determined in anesthetized cats. Vagal stimulation for 1 hr at 5, 10 and 20 imp/sec reduced the antral gastrin activity to about 75, 50 and 35 per cent, respectively. Corresponding figures for figures for 2 hrs stimulation was 45, 30 and 25 percent of the activity in unstimulated cats, thus showing a further reduction. Stimulation for 4 hrs did not produce any further reduction. Vagal stimulation for 2 hrs with all 3 frequencies reduced the gastrin activity in the mucosa of the proximal duodenum to unmeasurable levels.
Histamine Release from Rat Mast Cell Granules Induced by Bee Venom Fractions
Authors: Fredholm Bo , Hægermark ÖSten
Published: December 2008

Mast cell granules, obtained from sonically disintegrated rat peritioneal cells and suspended in sucrose, 0.34 M, were found to release histamine in the presence of bee venom. Three venom fractions were obtained by gel filtration; two of these had strong histamine releasing capacity, namely “F I” containing phosphatidase A, and “F III” with direct hemolytic properties. The third fraction, “F II”, which releases histamine from intact mast cells, had little effect on granules. Various possibilities for the release mechanism, namely phosphatidase activity, surface activity, and cation exchange, are discussed.
Effect of Acid in Proximal and Distal Duodenal Pouches on Gastric Secretory Responses to Gastrin and Histamine1
Authors: Andersson Sven , Nilsson Göran/sc> , Uvnäs Börje
Published: December 2008

In Pavlov and Heidenhain pouch dogs intestinal pouches of the duodenal bulb and distal duodenum were isolated. Perfusion of the bulbar pouch with decinormal hydrochloric acid produced a pronounced inhibition of the secretory response to gastrin in both the Pavlov and the Heidenhain pouch group. Perfusion of the distal duodenal segment with acid did not significantly inhibit the secretary response to gastrin. Instead an increase of the acid output was often seen following acid perfusion of the distal segment. Secretory responses to histamine were not significantly inhibited following bulbar acidification. The results indicate that the pH‐sensitive inhibitory mechanism of the duodenom is mainly located in the duodenal bulb. The mechanism seems to be particularly effective in suppressing the gastric acid response to gastrin.
An Instrument for Simultaneous Determination of Sodium and Potassium in Microsamples of Biological Material
Authors: Carlsson B. , Giacobini E. , Hovmark S.
Published: December 2008

An integrating microflamephotometer for simultaneous analysis of Na and K is described. The instrument has a sensitivity of 1 × 10‐3 moles of Na and K and is particularly suitable for determination of these ions in nanoliter samples of biological fluids or individuals cells.
Adrenergic Reinnervation of Anterior Chamber Transplants
Authors: Malmfors Torbjörn , Olson Lars
Published: December 2008

Reappearance of noradrenaline (NA) in the denervated sheep heart as a result of ingrowth of regenerating adrenergic nerves was first shown by Goodall (1951).

Growth of the sympathetic adrenergic neurons has also been studied with the Falck—Hillarp fluorescence technique for histochemical visualization of monoamines under various experimental conditions. Thus, ingrowth of noradrenaline nerve terminals into pineal gland transplants was observed by Owman (1964).

Little attention, however, has been given to the organization of newly formed sympathetic innervation apparatuses of transplanted tissues and organs. An investigation is therefore now being carried out to elucidate the development and appearance of such nerves in different grafted tissues.

Small pieces of various organs were aseptically transplanted to the anterior chamber of the eye of adult Sprague‐Dawley rats. Autologous, homologous and heterologous grafts (from N.M.R.I.‐mice) were used. Host eyes and grafts were observed daily in vivo with a dissecting microscope and the animals sacrificed after different time intervals. Transplants and irides of the host eyes were then prepared for fluorescence microscopy as described earlier (Norberg and Hamberger 1964, Malmfors 1965, see also Corrodi and Jonsson 1967).
Lung Damage and Lethality by Underwater Detonations
Authors: Andersen P. , Løken S.
Published: December 2008

Andersen, P. and S. Løken. Lung damage and lethality by underwater detonations. Acta physiol. scand. 1968. 72. 6–14.

Adult anesthetized rats were immersed to the larynx and subjected to underwater blast from two charges of 1 g tetryl each, both set off at a distance of 0.8 m from the target. The ratio: weight of the damaged lung/weight of the normal lung, expressing the degree of the lung hemorrhage, and the lethality (one hour survival) were both larger when the two charges were separated by a time interval of 8–25 μsec as compared to simultaneous detonation. The results indicate that the time integral of the pressure is more important for underwater blast damage than is the peak pressure attained.
A Comparison of the Subcellular Sites of Action of Reserpine and Benzquinamide
Authors: Lundborg Per , Stitzel Robert E.
Published: December 2008

P. Lundborgand Stitzel, R. E.A comparison of the subcellular sites of action of reserpine and benzquinamide. Acta physiol. scand. 1968.72. 53–61.

Both reserpinc and benzquinamide were capable of impairing thein uitrouptake of C14‐adrenaline by bovine and rabbit adreno‐medullary granules. however, they differed markedly in their relative potency. Thein vivostudies using mice and thein vivo‐in vitrostudies employing rabbits indicated that the time course of granular blockade after reserpine and benzquinamide injections also differed. Benzquinamide was shorter‐acting and less potent than was reserpine. Subcellular distribution studies indicated that while both drugs could impair thein vivouptake of3H‐α‐methyl noradrenaline, only reserpine administration resulted in both an increase in the amount of3H‐α‐methyl noradrenaline found in the supernatant fraction and an increase in the amount of3H‐α‐methyl normetanephrine recovered from the whole heart. It is concluded that while reserpine and benzquinamide have many qualitatively similar effects on amine uptake and depletion, differences in their actions on the subcellular level can be uncovered.
Antigravity Effects of Leg Exercise
Authors: ROSENHAMER G.
Published: December 2008

Rosenhamer, G. Antigravity effects of leg exercise. Acta physiol. scand. 1968. 72. 72–80,

To investigate the effects of leg exercise on the overall tolerance to exaggerated gravitational stress, 8 subjects were exposed for 13 min to a threefold increase of the force of gravity in centrifuge experiments (+ 3 Gz) while in the sitting position, both during motionless resting and when exercising at 600 kpm/min on a bicycle ergometer. In all subjects, continuous leg exercise prevented the occurrence of circulatory collapse. which otherwise became imminent in 5 subjects after 5 to 12 min in the resting condition as evidenced by blackout or rapid increase in heart rate. Subjectively, exercise was experienced as less stressful than the resting condition. The improved circulatory stability with exercise was also reflected by uniformity of individual heart rate responses, the group mean value increasing from 152 to 160 beats/min during the 6th to 12th min.
Glucose Tolerance in the Period Preceding the Appearance of the Manifest Obese‐Hyperglycemic Syndrome in Mice
Authors: Danieisson ÅKe , Hellman Bo , Täljedal Inge‐Bert
Published: December 2008

Danielsson, Å., B. Hellman and I.‐B. Täljedal, Glucose tolerance in the period preceding the appearance of the manifest obese‐hyperglycemic syndrome in mice. Acta physiol. scand. 1968. 72. 81–44.

After intraperitoneal glucose injections in suckling mice there was a higher frequency of glucosuria in those animals which later developed the obese‐hyperglycemic syndrome. The experimental design had a particular advantage in screening for the early identification of mice which are homozygous for the obese‐hyperglycemic gene. The observations also suggested that impairment of glucose metabolism represents a primary lesion in the obese‐hyperglycemic syndrome. The hypothesis that the accumulation of fat later in life only reflects an adaptation of the adipose tissue to the high circulating levels of insulin in the obese‐hyperglycemic mice deserves further attention.
Effects of Thrombin Infusions upon 131I‐labelled Fibrinogen in Dogs
Authors: Nordström Sam , Zetterqvist Eric
Published: December 2008

Nordström, S. and E. Zetterqvist. Effects of thombin infusions upon 131I‐labellad fibrinogen in dogs. Acta physiol. scand. 1968. 72. 85–99.

The elimination of 131I‐labelled fibrinogen was followed in 5 groups of dogs: 1. after thrombin infusion, 2. after thrombin infusion in heparinized dogs, 3. after simultaneous infusions of epsilon aminocaproic acid (EACA) and thrombin, 4. after simultaneous infusions of Trasylol and thrombin and 5. controls. Platelet number, fibrinogen concentration and radioactivity in plasma and fibrinogen were determined. Thrombin caused an immediate fall of both plasma and fibrinogen radioactivity. The plasma radioactivity, however, soon started to increase. This secondary increze of plasma radioactivity seemed to be due to fibrinogen‐fibrin degradation products. This indicates that the thrombin‐induced intravascular coagulation gives rise to a secondary fibrinolytic process. In heparinized dogs the coagulation‐promoting effect of thrombin was inhibited. EACA and Trasylol in large doses, given simultaneously with thrombin, had no effect on the coagulation process but prevented the secondary plasma radioactivity increase. The fibrinogen‐fibrin degradation products at different times were calculated. It was also possible to estimate the amount of synthetized fibrinogen at the different times. The highest mortality was obtained in the Trasylol‐thrombin group. A probable explanation is that Trasylol is more effective than EACA in preventing the compensatory clot‐dissolving fibrinolysis.
Changes in Cardiac Output upon Stimulation of the Hypothalamic Defence Area and the Medullary Depressor Area in the Cat
Authors: Folkow B. , Lisander B. , Tuttle R. S. , Wang S. C.
Published: December 2008

Folkow, B., B. Lisander, K. S. Tuttle and S. C:. Wang. Changes in cardiac output upon stimulation of the hypothalamic defenca araa and the medullary depressor area in the. cat. Acta physiol. scand. 1968. 72. 220–233.

The hypothalamic defence area and the bulbar depressor area, with related hypothalamic sympatho‐inhibitory structures, were topically stimulated while changes in cardiac output (C. O.). heart rate, stroke volume, central venous pressure and peripheral blood flow were studied in anesthetized‐curarized cats and dogs. Defence area stimulation induced up to two‐fold increases in C. O. and up to threefold increases in calculated work load for the left ventricle. The major part of the C. O. increase was directed to the skeletal muscles, where active cholinergic vasodilatation increased flow up to fivefold. Gastrointestinal and renal blood flows were promptly reduced and since this neurogenic flow reduction slightly prereded muscle vasodilatation, the C. O. increase could be preceded by a very brief phase of C. O. decrease. β‐adrenergic blockade could reduce the threefold increase in left ventricular work load by 50–60 per cent by eliminating the sympathetic drive on the heart. Depressor area stimulations produced an often profound reduction in C. O., sometimes prereded by a brief C. O. increase. Flow resistance fell, especially so in skeletal musrles, where an initial flow increase coincided with the transient C. O. increase; further, blood was pooled within the capacitance section. Blood loss or raised venous transmural pressure greatly potentiated these changes so that imminent cardiovascular collapse could be induced by this central depressor stimulation. The mechanisms involved in the mentioned, diametrically opposite cardiovascular patterns are. discussed.
Nervous Control of Urinary Bladder in Cats: IV. Effects of autonomic blocking agents on responses to peripheral nerve stimulation
Authors: Edvardsen Per
Published: December 2008

Edvardsen, P.Nervous control of urinary bladder in cats. IV. Effects of autonomic blocking agents on responses to peripheral nerve. stimulation. Acta physiol. scand. 1968.72. 231–247.

The bladder response to electrical stimulation of the parasymipathetic and sympathetic. nerves was recorded in anesthetized cats. Stimulation of the pelvic nerves caused a sustained bladder contraction. This response was not changed significantly by blockade withatropineat 5 cps stimulation, while at 30 cps only an initial contraction was obtained. It was abolished withhexamethomium, whereas it remained unchanged afterguanethidine, propranololanddibenzy‐linc. There was no evidence to suggest the presence of inhibitory fibres. Stimulation of the hypogastric nerves gave rise to an initial contraction followed by relaxation. On continuous stimulation the slope of the pressure volume curve was flattened in proportion to the strength of stimulation. However. during the relation phase of the detrusor muscle, the bladder outlet responded by contraction. The sympathetic response was blocked byguanethidine, butthis, in small doses, augmented the contraction phase.Propranololincreased the contraction phase, and in addition converted the relaxation to contraction. The contraction response could be blocked selectively by administration ofdibenzyline. It is suggested that adrenergic alpha‐receptors are present both at the bladder outlet, and in the detrusor muscle as well. but that in the latter case their presence is masked by the inhibitory beta‐receptors.
Effects of Phospholipase A and Lysolecithin on Some Electrical Properties of the Muscle Membrane
Authors: Albuquerque E X. , Thesleff S.
Published: December 2008

Albuquerque, E. X. and S. Thesleff. Effects of phospholipase A and lysolecithin on some electrical properties of the muscle membrane. Acta physiol. scand. 1968. 72. 248–252.

The effects of incubation with phospholipase A and lysolecithin on the resting membrane potential, action potential, input resistance and acetyleholine sensitivity of isolated extensor digitorum longus and soleus muscles of the rat were compared with those previously obtained with phospholipase C. A common action of the agents studied were that they in sufficient doses depolarized the muscle fibres and reduced the input resistance. In contrast to phospholipase C which irreversibly blocked action potential generation, phospholipase A and lysolecithin had little effect on membrance excitability. The sensitivity of chronically dencrvated muscle fibres to locally applied acetylcholine was unaffected by the two phospholipascs and by Iysolccithin. The difference in action between phospholipasr C and phospholipase A on electrogenic membrane excitability is suggested to be explained by the respective mode of lipolytic action of the two enzymes. Phospholipasc C hydrolyses the diglyceride — phosphate, ester linkage in phosphatides and thereby removes the phosphate head from the molecult while phospliolipase A cleaves one fatty acid ester linking leaving the polar heads of phospholipids intact. Lysolecithin possibly rearranges membrane structures by its high surface activity.
Formation of Bilirubin in the Dog Spleen
Authors: Bäcklund L. , Michaëlsson M.
Published: December 2008

No reliable informations on the normal plasma bilirubin contents in dog are given in the literature. In the present investigation a physiological sampling procedure and a modern analytic technique was used and data of blood from splenic veins, the abdominal aorta and a central vein were collected. The significance of the findings is discussed. In order to obtain information on the site of formation of bilirubin erythrocyte destruction was induced by injection of nicotinic acid and stored blood. On the basis of the results a bilirubin releasing mechanism in the spleen is concluded.
The Effect of Barbiturate Anesthesia and Hypothermia on the Edema Formation Caused by Subcutaneous Injection of 5‐Hydroxytryptamine in Mice
Authors: Svanes Knut
Published: December 2008

Local edema forniation caused by subcutaneous injection of 5‐hydroxytryptamine (5‐HT) was studied in unanesthetized, anesthetized normothermic and hypothermic mice. The edema was estimated quantitatively by a method involving the assay of extravasated trypan blue. Pento‐barbital was used for anesthesia. The hypothermic mice were kept at a rectal temperature of 21–22 C. In unanesthetized and anesthetized normothermic mice the edema formation increased with increasing doses of 5‐HT. At normal temperature light anesthesia greatly reduced the edema caused by 100 μg/ml 5‐HT, but did not modify the edema caused by 10 or 1 μg/ml 5‐HT. A lowering of the body temperature led to reduced edema formation, and the edema caused by 100 μg/ml 5‐HT was relatively more reduced than that caused by 10 μg/ml 5‐HT. The reduced edema formation under anesthesia and hypothermia might in part he due to increased constriction of the local arteries and arterioles under these conditions.
Changes in the Amount of Adrenergic Transmitter in the Female Genital Tract‐of Rabbit During Pregnancy
Authors: Rosengren E. , Sjöberg N.‐O.
Published: December 2008

The noradrenaline present in the female reproductive organs – ovary, oviduct, uterus, and vagina – of the rabbit is stored in adrenergic nerves. Fluorescence microscopy revealed that these nerves are related to the vascular bed and the smooth muscle walls; besides the vascular nerves the ovary also contains adrenergic nerves unrelated to the vessels. The adrenergic innervation of the genital organs originates from sympathetic ganglia located near the effector organs, as well as from pre‐ and paravertebral ganglia. During the former half of pregnancy a marked increase in neuronal noradrenaline occurs in the reproductive organs, except in the ovary. In the uterus and the vagina this increase is followed by a dramatic decrease in total noradrenaline during the latter half of pregnancy; by the end of pregnancy the uterus is almost completely devoid of noradrenaline‐containing sympathetic nerves. The findings are discussed in terms of an humoral influence on the adrenergic neurons supplying the female reprocluctive tract.
Cell Volume as a Factor Influencing Electrical and Mechanical Activity of Vascular Smooth Muscle
Authors: Johansson Börje , Jonsson Olof
Published: December 2008

The effects of variations in the extracellular osmolarity on the electrical and mechanical activity of the isolated rat portal vein were studied. Addition of sucrose or xylose (20–100 mmoles/l) to the “normal” solution caused inhibition of contractile activity which could be ascribed to changes in the electrical discharge pattern. Increasing osmolarity with urea produced transient inhibition, return to control activity, and, on return to normal solution, a transient excitation. Reducing osmolarity by 30–60 mOsm/l by decreasing the [Na+] and [Cl] of the medium caused sustained excitation with continuous spike discharge and tetanic contraction. Comparable decreases in the ionic concentrations but with osmotic substitution by sucrose or xylose had little influence on muscle activity. Substituting Na+ and Cl with urea on an equiosmolar basis caused excitation resembling that in hypoosmotic solution. If the smooth muscle cells are looked upon as osmotic cells with membranes that are freely permeable to H2O and urea but less permeable to sugar and ions, the results indicate a consistent correlation between cell volume and state of activity; shrinkage associated with inhibition, swelling with excitation. Changes in the transuiembrane concentration gradients for K+, Na+ and Cl‐, caused by the cellular volume changes, are not sufficient to explain the electrical responses. Changes in ionic membrane permeability are assumed to occur.
Secretory Responses and Respiratory Enzymes of the Rat's Submaxillary Gland after Repeated Teeth Amputations
Authors: Ohlin Per , Perec Carlos Jose
Published: December 2008

The effect of repeated teeth amputations on the secretory responses and the activities of succinic dehydrogenase, cytochrome oxidase and fumarse was studied in the rat's submaxillary gland.Repeated teeth amputations cause and enlargement of the gland.The secretory responses to adrenaline were found to be increased while those to acetylcholine, methacholine or stimulation of the parasympathetic secretory nerve were unchanged.The total activities of succinic dehydrogenase and fumarase were increased while that of cytochrome oxidase was unchanged.
Effect of Corticosterone and 11‐Desoxycortisol on the Extra‐Adrenal Chromaffin Tissue of the Rat
Authors: Lempinen Matti , Ojala Kari
Published: December 2008

Repeated injections of hydrocortisone and cortisone completely prevent the postnatal degeneration of extra‐adrenal chromaffin tissue of the rat, while treatment with desoxycorticosterone (DOC) is without such an effect.Also with massive doses of adrenocorticothropic hormone (ACTH) disappearance of the extra‐adrenal chromaffin cells can be prevented (Lempinen 1964).In the present study the effect of corticosterone and 11‐desoxycortisol on the postnatal chromaffin tissue have been studied.
Static Load‐Length Characteristics of Aortic Strips from Hypertensive Rabbits
Authors: Aars Harald
Published: December 2008

Elevated threshold and reduced sensitivity of aortic baroreceptors in hypertensive rabbits (Aars 1968) might be due to changes in the aortic wall, which is known to become stiffer in chronic hypertension.Since resetting of baroreceptors was present when studied a few days after development of hypertension, the static load‐length relationship of circular aortic strips from the receptor area was investigated in vitro.The strips from the hypertensive rabbits were thicker than normal when stretched by 3 g, and had higher elastic modulus than the strips from normal rabbits.Although not strictly comparable to in vivo conditions, the results suggest that at the same blood pressure, the aortic baroreceptors would be less stimulated in the hypertensive than in the normal rabbit, and that a given elevation of mean blood pressure would produce a greater increase of baroreceptor activity in the normal than in the hypertensive animal.Thus, the changes demonstrated in the aortic wall after 3–15 days of arterial hypertension may explain the resetting of aortic nerve activity in the hypertensive rabbits.
On the Physiological Significance of the Amplitude of the Endosomatic Galvanic Skin Reaction (GSR) in the Cat
Authors: Lang A.H.
Published: December 2008

Endosomatic galvanic skin reactions (GSR) evoked by electrical stimulation of the distal stump of a sectioned sciatic nerve have been recorded with metal macroelectrodes.It has been established that the amplitude of the negative phase of the endosomatic GSR is determined by (i) the stimulation parameters, (ii) the location of the recording electrodes, and (iii) the neuro‐sudomotoric activity before the stimulation.In addition, the GSR is influenced by both (iv) spatial summation and (v) temporal summation or cumulation, and may be influenced (vi) by the area of contact between the electrodes and the skin.On the basis of earlier and new observations in the recording of GSR's the conclusion has been drawn that the negative phase of the endosomatic GSR recorded with a macroelectrode is a composite potential which is produced in a circuit of resistive elements and unit potential generators (UPG), a group of effector cells that are probably situated in the wall of the sweat channel.The UPG's, each of which produce a unit potential (UP), seem to be coupled in parallel to each other and in series with the surface electrode.
Effect of pH and Temperature on the Uptake of Monoamines by Mouse Peritoneal Mast Cells in Vitro.
Authors: Jansson Sten‐Erik
Published: December 2008

The uptake of 5‐hydroxytryptamine, 5‐hydroxytryptophan, noradrenaline and dopamine by normal mouse peritoneal mast cells was studied by means of the histochemical fluorescence method.It was found that 5‐hydroxytryptamine uptake was significantly depressed by increasing pH from 7.0 to 8.9 and by lowering temperature to 20d̀ C when the amine concentration in the incubation medium was 1 μ/ml but not when the concentration was 10 μ/ml.The 5‐hydroxytryptophan uptake was to a high degree affected by similar pH and temperature alterations even when the concentration was as high as 200 μ/ml.This probably reflects a depression of the 5‐hydroxytryptophan decarboxylase activity.Noradrenaline and dopamine uptake was not significantly affected by pH or temperature alterations.These results indicate that normal mouse peritoneal mast cells take up 5‐hydroxytryptamine by an active as well as by a passive process and that the fluorescence observed after incubation with 5‐hydroxytryptophan is due to a high degree to decarboxylation into 5‐hydroxytryptamine.Noradrenaline and dopamine are apparently taken up by diffusion.Dopamine is taken up to some degree also by cells other than mast cells.
Dynamic Analysis of Muscle Spindle Endings in the Cat Using Length Changes of Different Length‐Time Relations
Authors: Lennerstrand Gunnar , Thoden Uwe
Published: December 2008

Primary and secondary muscle spindle endings in the ankle extensors of the cat were studied in response to length changes of ramp, triangular wave, sine wave and parabolic wave form with the intention of finding the most suitable input signal for an extensive dynamic analysis of the spindle during constant fusimotor input.

In dynamic tests the spindle endings were not found to obey linear length‐response transfer functions; no support for a power function relation could be obtained.Sine wave analysis was therefore not considered suitable for the purpose of determining the transfer functions.Attention was directed towards the use of step changes of velocity and of acceleration of length changes.No evidence for a specific sensitivity to acceleration was found in responses to ‘parabolic’ length changes.Responses interpreted as due to mechanical properties in the spindle elements resembling ‘stiction’ were obtained when ‘ramp’ length changes were applied.These effects were largely avoided when recurring ‘triangular’ length changes of constant velocity were used.It is concluded that the dynamic analysis might be adequately performed by subjecting the musscle spindles to periodically recurring length changes of triangular wave form giving step changes in velocity.
Thermography as an Aid in Hibernation Research
Authors: Brånemark P.‐I. , Johansson B. W.
Published: December 2008

The technique of thermogrphy is presented as an aid in hibernation research work as well as in other experimens in which the skin circulation is of interest
Changes in the Filtration Fractions in the Superficial and Deep Venous Drainage Area of the Cat Kidney due to Fluid Loading
Authors: Nissen O. I.
Published: December 2008

The effect of Ringer and mannitol loading on the filtration fractions of plasma entering the superficial and the deep part of the cortex was investigated by comparing the plasma concentrations of inulin and protein in the blood leaving the two venous drainage areas with the concentrations in arterial blood. The ratio between the deep and the superficial filtration fraction (FFD/FFS) decreased by some 20 per cent mainly due to a decrease in FFD. Inside the juxtamedullary glomeruli, which constitute a part of the glomeruli of the deep area, short‐circuits between the afferent and the efferent arterioles have been described, which cause the medullary blood supply to partly by‐pass the sites of ultrafiltration. The blood leaves the juxtamedullary glomeruli via relatively thick muscular efferent arterioles which regulate the medullary blood flow. The decrease in FFDmay result from a preferential augmentation of the flow through the medulla,viz.this indicates that the overall filtration fraction of the deep drainage area to a larger degree is governed by the presumably low filtration fraction of the juxtamedullary glomeruli
Posthypertonic Hemolysis in Sodium Chloride Systems
Authors: Zade‐Oppen A. M. M.
Published: December 2008

Human erythrocytes were exposed in vitro to hypertonic NaCl solutions and then to near isotonic media. The resulting posthypertonic hemolysis was studied as a function of hypertonic concentration and of time in the hypertonic medium. Providing that a critical concentration level (˜1.5 M NaCl) is exceeded, posthypertonic hemolysis is proportional both to the duration of exposure to hypertonicity and to the hypertonic concentration. The results have been interpreted in terms of a hypothesis put forward by Söderström (1944), who postulated that influx of salt occurred during the hypertonic phase and that a later reduction of the external concentration of 0.65 M NaCl will an influx of salt occur. An analysis of the results in terms of this hypothesis suggested that the permeability of the cells to NaCl increases with increasing external NaCl concentration: The permeability increase was very great in the region of 3 M NaCl. The counter‐current multiplier mechanism for kidney function has been criticised on the ground that red cells may not tolerate the tonicity changes postulated to exist in the kidney. In vitro experiments using slightly worse conditions than are believed to exist in the human kidney showed no significant hemolysis
The Reflection of the Age, Tissue and Solubility on the Amberlite CG‐50 Fractions of Denatured Collagens
Authors: Kulonen E. , Pikkarainen J.
Published: December 2008

Collagen was extracted and purified from the skins of young and full‐grown guinea pigs and from the skins and tendons of calf and cow, first with neutral salt solutions and acidic buffers in the cold and then the residue was gelatinized by stepwise heating. In the young animals the collagenous material which could be solubilized at +65°C already was increased markedly. The various denatured collagens were fractionated with Amberlite CG‐50 columns, eluted with buffers of increasing ionic strength and pH and finally with sodium hydroxide. The first fraction, emerging at pH 5.50, was large in the samples from soluble collagen (in comparison to insoluble), in the extracts from insoluble collagens of young animals (in comparison to adults) and in the collagenous fractions of tendon (in comparison to the skin). The gradient‐buffer‐eluted fraction which had been derived from insoluble collagen at progressively raised temperatures contained in abundance imino acids and hydroxy amino acids (in comparison to soluble collagens).
Position and Velocity Sensitivity of Muscle Spindles in the Cat. II. Dynamic Fusimotor Single‐Fibre Activation of Primary Endings
Authors: Lennerstrand Gunnar , Thoden Uwe
Published: December 2008

Impulse frequency responses of cat primary muscle spindle endings to ‘triangular’ length changes were recorded during stimulation of single dynamic fusimotor γ‐fibres at a constant rate. Endings in the ankle extensor and flexor muscles were studied. The dynamic fusimotor effects consisted of an unchanged or decreased position sensitivity of the endings and an increased velocity sensitivity to length increment. The effects were quantitatively similar in primary endings of all the muscle studied. In the velocity response, which was subdivided into ‘quick’ and ‘slow’ components, the ‘slow’ velocity response was increased much more by the stimulation than the ‘quick’ velocity response. The velocity sensitivity to length decrement could usually not be exactly determined. In the few cases in which it could be assessed, it seemed to be lower than the velocity sensitivity to length increment. When relatively high rates of stimulation and high velocities of length change were applied to the endings, a velocity dependent ‘saturation’ of the response appeared. In the discussion interest is focused on spindle mechanisms responsible for generating the observed response. It is suggested that the response is derived from intrafusal components with the mechanical and electrical characteristics of amphibian slow muscle fibres.
Afferent and Efferent Activity in the Renal Nerves of Cats
Authors: Astrom A. , Crafoord J.
Published: December 2008

In anesthetized cats efferent as well as afferent activity has been recorded in the kidney nerves. Pulse synchronous bursts of efferent impulses could regularly be recorded which after vagotomy and baroreceptor denervation were augmented and changed into a continuous type of discharge. The efferent activity could be modified by electrical stimulation of peripheral sensory nerves. It was inhibited by elevation of systemic blood pressure by i.v. noradrenaline injection, and greatly increased by lowering of blood pressure by i.v. acethylcholine. In the same nerves afferent activity also occurred, in a few instances spontaneously, but more often after elevation of renal vein pressure, elevation of arterial perfusion pressure (by pump), mechanical pressure applied to the hilus area or local dilution of the blood by close intra‐arterial injection of Ringer solution. Local ischemia for one minute or less elicited intense afferent activity. The results indicate that venous distension and increased subcapsular pressure are adequate stimuli for these afferent responses and that more than one kind of fibers are engaged in the afferent response. The functional significance of the afferent activity remains to be determined.
Influence of Puromycin and Anoxia on the Effect of Gonadotrophins on Ovarian Carbohydrate Metabolism
Authors: Ahrén Kurt , Hamberger Lars , Rubinsteini Lidia
Published: December 2008

An analysis of certain requirements for the gonadotrophic stimulation of ovarian carbohydrate metabolism has been performed. Whole ovaries from prepubertal and hypophysectomized rats were incubated in bicarbonate or Tris‐HCl buffer at 37° C. Puromycin, injected to the rats either before removal of the ovaries or added directly to the incubation medium, blocked the protein synthesis in the ovaries and caused a decrease in the rate of glucose uptake and lactic acid production. The stimulatory effects, however, of both LH and FSH on carbohydrate metabolism, which have been reported in detail previously (Hamberger and Ahrkn 1967) were not blocked by puromycin. Furthermore, this effect of FSHin vitroon carbohydrate metabolism could not be explained as due to a contamination by LH in the FSH preparation used. Ovaries incubated under anaerobic conditions showed increased rates of glucose uptake and lactate production. LH had no stimulatory effect on lactate production under these experimental conditions while puromycin still caused a significant decrease of this parameter. Addition of 2,4‐dinitrophenol to the medium markedly enhanced lactate production by the ovaries. Possible mechanisms for the gonadotrophic stimulation of carbohydrate metabolism in the ovary are discussed.
The Mechanisms behind the Rapid Blood Volume Restoration after Hemorrhage in Birds
Authors: Djojosugito1 Ahmad M. , Folkow Björn , Kovách Arisztid G. B.
Published: December 2008

The mechanisms responsible for the more efficient volume restoration after hemorrhage in birds as compared with mammals were studied in experiments on ducks. The results suggest that qualitativsly similar mechanisms operate to mobilize tissue fluid in ducks as in cats (see Öberg 1964). The most important factor seems to be a strong reflex vasoconstriction in the skeletal muscles, increasing considerably the pre‐ to postcapillary resistance ratio with a fall in capillary pressure as a result. In this way net fluid absorption is reflexly initiated in the tissue which contains the largest tissue fluid reservoir in the body. At the same time the pre‐capillary sphincters become secondarily relaxed, increasing the capillary surface area available for absorption. When in the course of a large blood loss arterial and venous pressures become reduced as well, this will further lower capillary pressure and do so in all tissues, thus enhancing fluid absorption. The results indicate that, from a quantitative point of view, considerable differences exist between ducks and cats. First, the reflex vasoconstriction and the subsequent capillary pressure fall are more pronounced in duck skeletal muscle. Second, the capillary surface area is approximately three times larger in duck muscle. These circumstances imply especially favourable conditions for rapid fluid absorption. It is probable that the greater resistance to blood loss and shock of most bird species as compared with mammals is directly related to their much greater capacity for fluid mobilization from the skeletal muscles.