bluuebunny/crossref_metadata_2025 huggingface dataset:
Acid‐Base Changes in Rat Brain Tissue during Acute Respiratory Acidosis and Baseosis
Authors: Pontén U.
Published: December 2008

The CO, buffer capacity of brain tissue in vivo was studied by measuring the tissue bicarbonate concentration at various tissue CO2 tensions in rats which were either hyperventilated, or breathed various CO2 concentrations spontaneously for 30 min. Measurements of the tissue lactate content indicated that the technique of freezing the tissue in situ did not lead to tissue hypoxia. The main increase in the tissue bicarbonate concentration at a given inspired CO2 concentration occurred within 30 min, but there was a slow further increase from 30 to 180 min. The values did not differ significantly between groups anesthetized with pentobarbital or phenobarbital and they were not influenced by variations of the inspired oxygen concentration from 20 to 50%. The mean tissue bicarbonate concentration was 16.0 meq/kg tissue H2O at a tissue CO2 tension (PtCO2) of 40 mm Hg. The buffer capacity of the tissue, defined as βCO2 = d log PtCO2/d log (HCO3/PtCO2 · S2) was 1.5. This means that when the CO2 tension was changed from 20 to 120 mm Hg, the tissue bicarbonate concentration increased from 12.5 to 22.5 meq/kg tissue H2O. Theoretical derivation of an equivalent buffer system with the same buffer capacity showed that at least 35 mmoles of buffer/kg tissue H2O were needed to explain the in vivo buffer capacity of the tissue. The theoretical buffer system made it possible to derive buffer base values for the tissue, and to construct a curve for the calculation of base excess values.
The Action of Insulin on Glycogen Synthesis in Rat Diaphragm. A comparative study of in vitro and in vivo effects
Authors: Søvik Oddmund
Published: December 2008

Insulin, administered by intraperitoneal injection in doses which did not significantly alter the blood glucose, caused a 40‐fold increase in the incorporation of 14C‐glucose into glycogen of the diaphragm. To study this effect of insulin, activities of glycogen synthetase and levels of glucose‐6‐P were determined, and compared with the'corresponding values in the isolated diaphragm. Insulin, in vitro, caused a 2‐fold increase in the glucose‐6‐P independent form of glycogen synthetase, while the enzyme activity in the presence of glucose‐6‐P remained unchanged. When glycogen synthetase was studied in vivo, no change of the glucose‐6‐P dependent to the glucose‐6‐P independent form of the enzyme was observed. Insulin, in vitro, did not affect glucose‐6‐P levels when glucose was excluded from the incubation medium. After insulin in vivo glucose‐6‐P levels were increased by 75 per cent. The results suggest that insulin in vivo can markedly stimulate glycogenesis without causing any synthetase D → I conversion. It is suggested that glucose‐6‐P plays an important role in the regulation of muscle glycogen synthesis in vivo.
Monoamine Oxidase Activity in the Bovine Splenic Nerve Granule Preparation
Authors: Roth R. H. , Stjärne L.
Published: December 2008

Monoamine oxidase (MAO) activity was determined in fractions obtained from bovine splenic nerve with both dopamine (DA) and noradrenaline (NA) as substrates. DA was found to be a much better substrate for MAO than NA. The bulk of the MAO in this preparation was found in the nerve granule fraction, which by electron microscopic evaluation seemed to be largely free from mitochondrial contamination. These findings suggest that bovine splenic nerve in addition to mitochondrial bound MAO also contains a form of MAO, with a substrate preference for DA, which seems to be associated with the nerve granules.
Circulatory and Respiratory Adaptation during Prolonged Exercise in the Supine Position
Authors: Ekelund L. G.
Published: December 2008

Circulatory and respiratory changes during prolonged, non‐steady state exercise in the supine position were studied by the heart catheterization technique in six healthy young men of average physical fitness. The work load was chosen so that they could perform supine exercise for one hour. This load gave a mean heart rate of about 128 beats/min after 10 min and 142 beats/min after 50 min of work. The circulatory changes during these experimental conditions were characterized by a constant cardiac output and a continuous increase in heart rate, indicating a continuously falling stroke volume. The systemic arterial blood pressure fell continuously, but the mean pulmonary arterial pressure fell markedly between 10 and 20 minutes' work and then remained unchanged. The acid base status was fairly stable during exercise. The respiratory response was characterized by a slight increase in total ventilation, an unchanged alveolar ventilation and a slight increase in dead‐space ventilation. The small increase in total ventilation was due to a small increase in respiratory rate and tidal volume. The overall ventilation‐perfusion relationship was unchanged. Both circulatory and respiratory changes may be explained by a decreased tonus in the capacity vessels with a shift in the distribution of the blood.
The Effect of Cholecystokinin‐Pancreozymin Preparations on Hepatic Bile Output in Fasting and Digesting Dogs
Authors: Jonson G. , Svartengren G. , Thulin L.
Published: December 2008

The output of hepatic bile was studied in 3 unanesthetized dogs with permanent external common duct fistulas during infusion of cholecystokinin‐pancreozymin preparations. The doses were such that the secretin content was negligible. Infusion during fasting doubled the output. Infusion during digestion of food with bile gave either a decrease of the output or an initial increase followed by a decrease. These patterns appear to be related to the gastric and duodenal activity during the experiments. Physiologic or pharmacologic interventions on hepatic bile output should thus be evaluated only when side effects on gastro‐intestinal motility and secretion can be excluded.
A Study of Thirst and Other Effects of an Increased Sodium Concentration in the 3rd Brain Ventricle
Authors: Anderson B. , Jobin M. , Olsson K.
Published: December 2008

The characteristics of thirst elicited by injections of hypertonic NaC1‐solution into the 3rd brain ventricle were studied in goats supplied with permanent ventricular canola. Animals in normal water balance drank 1.5 to 2.0 1 of water within 2 min after the intraventricular injection of 0.1 ml of 0.85 M NaC1. In the hydrated animal this thirst response was markedly diminished or completely absent. If the goats were not allowed to quench their thirst immediately after the intraventricular injection of hypertonic NaC1, the urge to drink gradually became weaker and disappeared after about 20 min. Single or repetitive injections of 0.1 ml of 0.85 M NaCl into the 3rd brain ventricle were further found to cause a conspicuous increasz in urinary excretion of Na+ and C1– and to inhibit temporarily an established water diuresis. Aldosterone treatment did not prevent the increase in urinary electrolyte excretion occurrinz after injections of hypertonic NaCl into the 3rd ventricle.

Repetitive injections of 0.1 ml of 0.85 M NH4Cl or of 1.7 M d‐glucose into the 3rd ventricle, or injections of 0.1 ml of 0.85 M NaCl into the lateral ventricle did not induce drinking or cause any increase in urinary electrolyte excretion.
Application of High‐Frequency Reflectometry for Measurement of Minute Changes in Electrolytic Conductance
Authors: Haapanen L.
Published: December 2008

The paper presents a method of measuring small variations in electrolytic conductance applicable also to dynamic measurements. By means of a probe immersed in the solution a high‐frequency field is applied, variations in the absorption of which are detected by a special instrument, the H‐F reflectometer, and indicated on separate meters as changes in resistive and capacitive components of the combined impedance, of probe and electrolyte. At the frequency used, 1085 kc/s, absorption maximum occurs at conductivities around 10–4 ohm‐1 cm‐1, at which a change in conductivity of 10‐1 ohm‐1 cm‐1 can be measured with reasonable accuracy in long‐term experiments and transient changes of 10–8 ohm‐1 cm‐1 can be detected using variations in the capacitive component as index. By means of a graphical method an analysis is made of an equivalent circuit simulating the electrical properties of an electrolyte. It is shown that a series circuit of a varying resistance and a fixed‐value capacitance approximates several of the characteristics of a solution.
Recording of the Ionic Efflux during Single Action Potentials in Nitellopsis Obtusa by Means of High‐Frequency Reflectometry
Authors: Haapanen L. , Skoglund C. R.
Published: December 2008

The ionic efflux during a single action potential of the alga Nitellopsis obtusa was recorded by measuring the increase in conductivity of the extracellular fluid. The conductivity changes are reflected as variations in absorption of a high‐frequency field applied by a specially designed probe placed in the external medium close to the alga and connected to a high‐frequency reflectometer. The combined characteristics of probe/solution and reflectometer are given. Most experiments were performed on algae in distilled water, comparative experiments with lake water having shown that this arrangement does not introduce any significant changes in the activation processes studied. The possibility of dynamic recording of ionic fluxes is illustrated by oscillograph records showing the temporal relation between the ionic concentration change and the action potential; that the method is suitable for quantitative measurements is demonstrated by inkwriter records showing the stepwise increases in concentration caused by intermittent stimulation during hour‐long experiments. Quantitative data on the increments in ionic concentration associated with a single impulse, and on the total increase resulting from a number of stimuli, are presented and compared with chemical analyses showing the ions involved to be K+ and C1‐‐. Satisfactory correspondence was obtained between the values of the conductivity measurements, tentatively expressed as KC1 concentration, and the chemical analysis. The average values for the K+ efflux were 2 times 103 to 4 times 103 pmole/cm2. impulse; preliminary studies showed the C1– efflux to be of approximately the same order.
Effects of Adrenaline on Coronary Flow in Isolated Perfused Rat Hearts
Authors: Glomstein Anders , Hauge Anton , ØYe Ivar , Sinclair Derek
Published: December 2008

The mechanism for adrenergic regulation of coronary flow has been studied in an isolated, working rat heart preparation. It is concluded that adrenaline affects coronary flow in this preparation through three separate modes of action: 1. Constriction of the coronary resistance vessels mediated through a‐type of adrenergic receptos in these vessels. 2. Dilatation of the coronary resistance vessels mediated through β‐type of adrenergic receptors in these vessels. J. Dilatation of the coronary resistance vessels as a consequence of increased myocardial metabolism after adrenaline.
Studies of the Importance of the Thyroid and the Sympathetic System in the Defence to Cold of the Goat
Authors: Anderson B. , Ekman L. , Hökfelt B. , Jobin M. , Olson K. , Robertshaw D.
Published: December 2008

Markedly hypothyroid goats were found to retain the ability to maintain body temperature during acute cold exposure (‐ 3° C), and to react to local cooling of the hypothalamic thermoregulatory “centre” by a rise in body temperature. However, the shivering response to external cold and to hypothalamic cooling was strongly accentuated, and the increase in urinary excretion of cate‐cholamines (especially of adrenaline) was generally much greater than that of the euthyroid goat. In 3 out of 4 hypothyroid goats studied, the catecholamine excretion at room temperature was also higher than that found in euthyroid goats. During acute cold exposures the blood glucose of the hypothyroid goats rose by about 300 per cent as compared to a rise of about 20 per cent in the euthyroid animals. It is concluded that to maintain thermal homeostasis in the cold markedly hypothyroid goats have to compensate the lack of thyroid hormone by a conspicuous increase in adrenaline secretion. Bilateral splanchnicotomy in the euthyroid goat resulted in practically complete absence of adrenaline in the urine, but did not present the rise in body temperature and the shivering seen during local cooling of the anterior hypothalamus. However, the hyper‐glycemic response to hypothalamic cooling was blocked completely.
The Effect of H+— and Lactate Ions on the Electrical Activity and Content of High Energy Phosphate Compounds of Taenia Coli from the Guinea Pig
Authors: Aaberg Gunnar , Mohme‐Lundholm Ella , Vamos Nandor
Published: December 2008

Reduction of the pH in Krebs solution with 0.05–0.4 units by adding lactic acid or acetic acid to a final concentration of 0.1–1.0 mmoles/l or by increasing the CO2 concentration from 3–12 % (pH change 0.28) in the gassing mixture caused relaxation of isolated taenia coli from the guinea pig. In determining the electrical activity of the membrane of the muscle by the “sucrose gap” method, it was found that a pH reduction inhibited the action potential, and with yet lower pH values hyperpolarization was observed. In K+‐depolarized muscle a similar pH reduction had a tension‐increasing effect. Na+‐lactate increased the electrical activity of the membrane and had a tension‐increasing effect. — The addition of lactic acid in a concentration of 1 mmole/l which relaxed the carbacholine stimulated muscle, had no effect on the content of high energy phosphate compounds. It seems probable that the relaxing effect of H+‐ions was a result of its inhibitory effect on the electrical activity of the membrane.
Choline Acetylase in Normal and Denervated Submaxillary Glands of Rats after Repeated Teeth Amputations
Authors: Ohlin Per , Perec Carlos Jose
Published: December 2008

The size of the rat's submaxillary gland and the total activity of choline acetylase in the gland were markedly and similarly increased after repeated teeth amputations. Preganglionic parasympathet‐ic denervation caused an atrophy of the gland and a pronounced decrease in enzyme activity. It did not inhibit the effects of repeated teeth amputations. Postganglionic sympathetic denervation alone caused a slight decrease in gland weight and an increase in choline acetylase activity. The effect of repeated teeth amputations was partly inhibited in sympathetically denervated glands. It was completely abolished in both parasympathetically and sympathetically denervated glands.
Presence of Free and Conjugated Noradrenaline in Human Cerebrospinal Fluid
Authors: Dencker S. J. , Häggendal J. , Ilves‐Häggendal M.
Published: December 2008

The noradrenaline (NA) in the lumbar cerebrospinal fluid (CSF) was estimated by the trihydroxy‐indole reaction in patients with lumbar root syndromes or with mental diseases. The mean values found were 0.2±0.08 pg/l (7 cases) and 0.5±0.03 μ g/l (68 of 72 cases), respectively. In 4 cases of the latter group much higher values were obtained. In one case adrenaline was found in the CSF. So significant amounts of dopamine were demonstrable in the CSF.

Conjugated NA in the CSF, which was detected in 19 of 22 cases studied, increased after oral administration of NA. The origin of free and conjugated NA in CSF with respect to the blood‐SCF barrier is discussed.
Studies on the Transport and Life‐span of Amine Storage Granules in the Adrenergic Neuron System of the Rabbit Sciatic Nerve
Authors: Dahlström Annica , Haggendal Jan
Published: December 2008

The accumulation of noradrenaline above a ligation of the albino rabbit sciatic nerve and the noradrenaline content of the adrenergic fibre system emanating from the sciatic nerve were determined biochemically. Using the obtained data the transport and life‐span of amine granules were calculated to be about 3 mm per hr and about 50 days, respectively.
Constancy of d(+)Xylose Space in Man during Brief Exercise
Authors: Hasan J. , Karvonen M. J. , Piironen P. , Ruosteenoja R.
Published: December 2008

Measuring the concentration of xylose in blood at intervals between the 15th and 65th minute following a rapid i.v. injection of 12.5 g of d (+)xylose into 5 healthy males, we found it decreasing at a steadily diminishing rate, indistinguishable from that of a single exponential process with an average half‐period of about 60 min. Starting at 30 min after the injection, the subjects worked for 10 min on a bicycle ergometer at 18 kpm/sec. This activity did not alter significantly the linear time course of the logarithm of blood xylose concentration, either during the exercise or in the 25 min of observation following it. A rough evaluation of possible contributing factors shows that any increase in the apparent volume of distribution of xylose during or after the exercise cannot have exceeded approximately 12 per cent of its average initial value, which was about 21 per cent of the subjects' average body weight. Thus, observations on human subjects in physiological conditions failed to confirm the contention, derived from findings in electrically induced muscular contractions of anesthetized animals, that the permeability of the cell membrane to sugars is increased to a physiologically important extent during muscular exercise, the alteration allegedly resembling closely that brought about by insulin. We conclude that the discrepancy between the present findings and those reported previously may be due to an interspecies difference in mechanisms of regulation or, rather, it reflects the fact that previous experiments involved far from physiological conditions, likely to induce e.g. fluid shifts and consequent distortions of interpretation.
Suppression of Cortical Spontaneous Barbiturate Spindles via Specific and Unspecific Projection Spinal Pathways
Authors: Anderson Sven A.
Published: December 2008

The effects of peripheral adequate stimulation on cortical barbiturate spindles were investigated after spinal lesions in lightly anesthetized cats. Certain effects can be evoked from the specific projection pathways, the dorsal columns and the spino‐cervical tract, but a generalized suppression of cortical spindles was obtained mainly via two other pathways. One of these pathways, identified as the bilateral ventral flexion reflex tract, ascends in the ventral funiculus. The other pathway ascends in the dorsolateral funiculus and consists of thin, possibly unmyelinated fibres. Both pathways could be activated by low and high threshold receptors in bilateral fields and gave a desyn‐chronization of cortical spindles outlasting the duration of stimulation. The cortical effects mediated via the specific projection spinal pathways were mainly found in somatosensory projection areas with a local abolition of spindles and increased background activity. In very light anesthesia a small and shortlasting generalized effect could sometimes be obtained.
Serum Proteins in the Hedgehog
Authors: Larsen Bodil , Tönder Olav
Published: December 2008

Hedgehog serum proteins were studied by physical, chemical and immunological methods. The paper electrophoretic and immunoelectrophoretic patterns did not differ greatly from those of human serum. In paper electrophoresis two beta‐bands were found, the beta2‐band being the most conspicuous. In the immunoelectrophoretic pattern, the form of the “rapid” lipoprotein‐line was found to vary with temperature and duration of storage of serum. Autoradiography showed transferrin in hedgehog serum to be a beta2‐globulin. Antibody activity was found in two different fractions after gel filtration or ultracentrifugation of serum, probably representing antibodies of the 19S and 7s types.
Glycogen Phosphorylase: A Specific Secondary Target System for Adrenergic Stimulation in the Heart
Authors: ØYE IVAR
Published: December 2008

Glycogen phosphorylase (α‐1,4‐glucan:orthophosphate glucosyltransferase, EC 2.4.1.1.) was studied in the isolated rat heart in the asystolic and the working state. Increasing work loads did not affect the amount of phosphorylase α. Anoxia was found to increase the levels of phosphorylaseaL, but this effect could be completely prevented by pretreatment with adrenergic beta receptor blocking agents. These agents also lowered the levels of phosphorylaseain the heartin vivoto levels close to those found in the isolated, perfused heart. It is concluded that the phosphorylase transformation system in the rat heart under physiological conditions serves as a specific secondary target for adrenergic stimulation.
Response of Rat Atrium to Propranolol and Catecholamines in Various States of Thyroid Action
Authors: Hirvonen Leo , Paavilainen T. O. A.
Published: December 2008

The effect of propranolol on spontaneous beating, and the response of this to adrenaiinc and noradrenaline, was studied in hypothyroid, euthyroid and thyroxine treated isolated atrium of the rat hcart. A significant negative chronotropic effect was noted in thyroxinized preparations; in other groups this change was less significant. The inotropic property remained unchangcd in control conditions. A propranolol dose of 1 μg/ml blocked the positive chronotropic effect of adrenaline and noradrenaline completely in euthyroid and thyroxinized atria and partially in the hypothyroid ones. A competitive antagonism was observed between propranolol and catecholainines in the various preparations when contraction force and mechanical output werr measured. Thc positive inotropic effect of adrenaline and noradrenaline was highest in the hypothyroid and lowest in thr thyroxinized series. Only quantitative differences were ohserved in the responses of the atria to propranolol and catecholaminrs in various states of thyroid action.
Histamine Release from Rat Mast Cells Induced by a Mast Cell Degranulating Fraction in Bee Venom
Authors: Fredholm Bo , Haegermark ÖSten
Published: December 2008

Bee venom is known to contain high amounts of phosphatidase A and to cause degranulation and histamine release in rat mast cells. In the present study bee venom was fractionated on Sephadex G 50, whereby the phosphatidase A (Fraction F I) was separated from the histamine releasing activity (Fratcion F II). Various aspects of the F II‐induced histamine release from rat peritoneal mast cells were studied, namely the dose‐response curve, the time course of the reaction, the pH and temperature dependency, and the influence of inhibitors. It is concluded that this bee venom fraction acts by a mechanism similar to that of compound 48/80. This is in contrast to findings reported for melittin, a histamine releasing bee venom fraction described by other authors.
Circulatory and Respiratory Adaptation during Prolonged Exercise of Moderate Intensity in the Sitting Position
Authors: Ekelund L.‐G.
Published: December 2008

Circulatory and respiratory adaptation during prolonged exercise of moderate intensity in the sitting position were studied with heart catheterization technique in 6 healthy young men of ordinary, physical fitness. The work load was chosen so that they worked at a level of 57.3 per cent of the rate of work they could perform at a pulse rate of 170 beats/min. This load gav a mean heart rate of 126.7 beats/min after 10 min and 138.5 beatslmin after 60 min of work. The circulatory changes under these experimental conditions were characterized by a constant cardiac output with a continuous increase in heart rate and a continuously falling stroke volume. The systemic arterial mean blood pressure fell slightly but significantly and the mean pulmonary arterial pressure also decreased significantly from 10 to 40 min work. The total blood volume decreased 7.2 per cent from rest to 10 min work and then remained unchanged. The respiratory response was characterized by a numerical increase (P<0.1) in total ventilation, dead space ventilation and an unchanged alveolar ventilation. The respiratory quotient increased from rest to the beginning of the exercise and then decreased significantly. The observed changes during prolonged exercise may be explained by a decreased vasomotor tone with a change in the compliance of the capacity vessels and the distribution of the blood volume. The relative level of work intensity seems to be more important than the body position to maintain a steady state.
A Mathematical Definition of the Tonicity of the Galvanic Skin Reaction in the Cat
Authors: Lang A. H.
Published: December 2008

Little attention has previously been paid to the time characteristics of the galvanic skin reaction (GSR). According to recent studies carried out in this laboratory, the intensity and time course of the GSR can be controlled differentially by the CNS. For analysing GSR dynamics quantitatively a reliable method of measuring its time characteristics is needed. The paper deals with this general problem of measurement. Based on empirical material it is suggested that the ratio of the area of the GSR curve, measured planimetrically, to the product of its peak amplitude and the recording speed, is a reliable index of the tonicity of most GSRs recorded under various experimental conditions. The tonicity or time index, designated as the TI of the GSR, has the dimension of time. It is expressed in seconds and its value is independent of the recording parameters used. Actually the TI is equal to the time for decay of the ‘integrated and averaged’ GSR curve to half its maximum amplitude. For detailed analysis the TIs of separate sections of the GSR can be determined in the same way as that for the total reaction. Examples from different experiments illustrating the need and the employment of the new method of analysis are given.
Blockade of the Calorigenic, Hyperglycemic, Lactic Acid‐producing and Fatty Acid‐mobilizing Effects of Adrenaline by an Adrenergic β‐receptor Blocking Agent (Pronethalol) in Experiments on the Rabbit
Authors: Svedmyr Nils
Published: December 2008

Pronethalol in a dose of 6 mg/kg greatly inhibited the stimulatory effect of adrenaline given in an intravenous infusion of 0.5 μ/kg/min for 60 min, on the oxygen consumption in the rabbit. Pronethalol also blocked the stimulatory action of adrenaline on the lactic acid production, and its hyperglycemic and fatty acid‐mobilizing effects. The relationship between these effects are discussed.
Muscle Glycogen during Prolonged Severe Exercise
Authors: Hermansen Lars , Hultman Eric , Saltin Bengt
Published: December 2008

10 well trained and 10 untrained subjects worked to complete exhaustion on a bicycle ergometer with work loads averaging 77 (76–87) per cent of their individual maximal aerobic power. Determinations of glycogen used by working muscles (biopsy of lateral portion of the quadriceps femoris muscles) and of combusted carbohydrate (Vo2 and RQ) were performed at certain intervals from the start of work to exhaustion. At a combustion rate of about 3 g carbohydrate per minute (RQ around 0.9 or higher) and at average values for glycogen in resting muscle of 1.6 (1.1–2.5)g/100 wet muscle, the effective work time was around 85 min for the untrained and 90 min for the trained subjects. At the end of the exhaustive exercise the glycogen content averaged 0.06 g in the untrained and 0.12 g/100 g wet muscle in the trained subjects. A close relationship between utilized glycogen and combusted carbohydrate was found, and it seems highly probable that at high relative workloads primarily the glycogen stores in the exercising muscles will limit the capacity for prolonged strenuous work.
Diet, Muscle Glycogen and Physical Performance
Authors: Bergström Jonas , Hermansen Lars , Hultman Eric , Saltin Bengt
Published: December 2008

The muscle glycogen content of the quadriceps femoris muscle was determined in 9 healthy subjects with the aid of the needle biopsy technique. The glycogen content could be varied in the individual subjects by instituting different diets after exhaustion of the glycogen store by hard exercise. Thus, the glycogen content after a fat ± protein (P) and a carbohydrate‐rich (C) diet varied maximally from 0.6 g/100g muscle to 4.7 g. In all subjects, the glycogen content after the C diet was higher than the normal range for muscle glycogen, determined after the mixed (M) diet. After each diet period, the subjects worked on a bicycle ergometer at a work load corresponding to 75 per cent of their maximal O2uptake, to complete exhaustion. The average work time was 59, 126 and 189 min after diets P, M and C, and a good correlation was noted between work time and the initial muscle glycogen content. The total carbohydrate utilization during the work periods (54–798 g) was well correlated to the decrease in glycogen content. It is therefore concluded that the glycogen content of the working muscle is a determinant for the capacity to perform long‐term heavy exercise. Moreover, it has been shown that the glycogen content and, consequently, the long‐term work capacity can be appreciably varied by instituting different diets after glycogen depletion.
Secretory Potentials, Secretory Rate and Water Permeability of the Duct System in the Cat Submandibular Gland during Perfusion with Calcium‐Free Locke's Solution
Authors: Petersen O. H. , Poulsen J. H. , Thorn N. A.
Published: December 2008

It has previously been shown that the cat submandibular gland is unable to secrete in the absence of calcium. As the formation of saliva is the result of transport processes in the acini as well as the duct system, the effect of omitting calcium was investigated in both these parts of the gland. In the acini secretory potentials which are signs of an active ion transport, were recorded, and in the duct system water permeability was measured using tritium labelled water. In spite of severe reduction in the secretory ability of the gland, secretory potentials of normal size could still be evoked in the absence of calcium, but the shape of the potentials was altered. No striking effects on the water permeability of the duct system could be detected.
Further Studies on the Effect of Follicle Stimulating Hormone on Amino Acid Transport in the Isolated Rat Ovary
Authors: Ahrén Kurt , Hamberger Lars , Hartford Marianne
Published: December 2008

Amino acid uptake by isolated whole ovaries from prepuberal rats has been studied employing the non‐utilizable amino acids α‐amino‐isobutyric acid (AIB) and 1‐aminocyclopentane carboxylic acid (cycloleucine), as well as the normal amino acid proline. The ovaries showed a nearly linear uptake of AIB during 4 hrs of incubation while cycloleucine reached steady‐state levels in the tissue after approximately 1 hr. The uptake of proline resembled that of cycloleucine. Ovaries from rats which had received an i.v. injection of FSH before the extirpation of the ovaries showed both a higher rate of AIB‐uptake and higher levels in the steady‐state distribution of cycloleucine than ovaries from control rats. Dose‐response relationships as well as the importance of the time interval between the FSH injection and the start of incubation were analysed. Addition of FSH directly to the incubation medium had no stimulatory effect on amino acid uptake. Intraperitoneal injection of puromycin before the injection of FSH blocked the effect of the hormone on AIB‐uptake. Various possibilities to explain the lack of in vitro effect of FSH on amino acid uptake are discussed in relation to the observations with puromycin.
Studies on Morphological Changes and Histamine Release Induced by Bee Venom, n‐Decylamine and Hypotonic Solutions in Rat Peritoneal Mast Cells
Authors: Bloom Gunnar D. , Haegermark ÖSten
Published: December 2008

Histamine release and concomitant morphological changes in rat peritoneal mast cells were studied under various conditions. It was found that mast cells react somewhat differently, depending on the means by which histamine release was brought about. Bee venom produced effects similar to those of compound 48/80 and seemed to trigger an active cell process with extrusion of mast granules as a final result. n‐Decylamine and hyposmotic solutions appeared to bring about histamine release by affecting the integrity of mast cell fine structure resulting in a breakdown of plasma membrane and cellular compartments.
Cholinacetylase in Innervated and Denervated Sympathetic Ganglia and Ganglion Cells of the Cat
Authors: Buckley G. , Consolo S. , Giacobini E. , Sjöqvist F.
Published: December 2008

>Cholinacetylase (ChAc) activity was determined in normal and denervated lumbosacral sympathetic ganglia of the cat. Preganglionic denervation resulted in 98 per cent decrease of the ChAc. The postsynaptic ChAc activity was related to the proportion of presumably cholinergic cell bodies in the denervated ganglion. ChAc was found in about 13 per cent of the cell bodies in the 7th lumbar ganglion before as well as after denervation. The average enzyme activity in the cell decreased by about 50 per cent after denervation. The results indicate that ChAc is rather specifically located in cholinergic presynaptic and postsynaptic structures. The data favour the concept that sympathetic ganglia of the cat contain at least two different cell populations with distinct cytochemical, histochemical and pharmacological characteristics.
The Effect of Reserpine on Transmission in the Spinal Cord
Authors: Engberg I. , Lundberg A. , Ryall R. W.
Published: December 2008

Engberg, I., A. Lundberg and R. W. Ryall. The effect of reserpine on transmission in the spinal cord. Acta physiol. scand. 1968. 72. 115–122.

In unanesthetized acute spinal cats, in which monoamine oxidase is inhibited, an i.v. injection of reserpine gives a profound depression of transmission from the flexor reflex afferents (FRA) to primary afferents and motoneurones. The effect is similar to that evoked by the monoamhe precursors DOPA or 5‐HTP including a release of late reflex actions from the FRA. In chrohic spinal cats reserpine has no effect on transmission from the FRA. The effect of reserpine is partially reversed by the 5‐HT antagonist Deseril (which also partially reverses the effect of 5‐HTP) but not by phenoxybenzamine (which reverses the effect of DOPA). It is postulated that reserpine acts by liberation of 5‐HT from descending fibres. The possibility that reserpine also acts on transmission from the FRA through liberation of noradrenaline is discussed.
Effect of Reserpine on the Urinary Excretion and the Tissue Levels of Noradrenaline in the Rat1
Authors: Andén Nils‐Erik , Henning Matts
Published: December 2008

Andén, S.‐E. and M. Henning.Effect of reserpine on the urinary excretion and the tissue levels of noradrenaline in the rat. Acta physiol. scand. 1968.72. 134–138.

Reserpine. (10 mg/kg i.p.) caused R redtiction to about 10 per cent of the normal in the amoumt of noradrenaline excreted in the urine by adreno‐demedullated rats. After 48 hrs the noradrenalinc exerction had increased significantly (P<0.095) to ahout 30 per cent and after 72 hrs to about 55 per cent of normal. Simultaneously with these increases the sympathetic. nerve function is restored partially and completely, respectively. The noradranaline levels of sympathetically innervated organs were reduced almost completely after the reserpine injection and there was no significant change of them at the time of the functional recovery. Similarly results were obtained when an additional dose of reserpine (1 mg/kg i.p.) was given 72 hrs after the first one.
Nervous Control of Urinary Bladder in Cats: II. The expulsion phase
Authors: Edvardsen Per
Published: December 2008

Edvardsen, P. Nervous control of urinary bladder in, cats. II. The expulsion phase. Acta physiol. scand. 1968. 72. 172–182.

The volume threshold for micturition is altered by transection of the brain stem at variousu levels and also by section of the sympathetic nerves to the bladder. The aim of the present experiments has been to investigate whether the supraspinal influences are brought about by means of changes in peripheral sympathetic mechanisms. Mostly male cats were investigated using the ‘direct cystometry’ method. Cystometrograms obtained preoperatively were compared with those obtained after peripheral sympathectomy and during the phase of increased motility following laparotomy. Then the effects of brain stem transection on the micturition threshold in the. presence and absence of sympathetic innervation were compared. The peripheral factor responsible for eliciting the micturition reflex was found to be the tension in the bladder wall as assessed from the intravesical pressure. The lower volume threshold found after sympathectomy is due to the hypertonicity of the bladder following this procedure. The tonic supraspinal influence on the micturition reflex, on the other hand, was not altered by interruption of the sympathetic nerve supply to the bladder. Thus, the expulsion of urine is controlled by two different mechanisms, namely a peripheral regulation of the tension in the bladder wall and a supraspinal regulation of the micturition reflex threshold.
Tonic Supraspinal Mechanisms Influencing the Intestino – Intestinal Inhibitory Reflex
Authors: Johansson Börje , Jonsson Olof , Ljung Bengt
Published: December 2008

Johansson, B., O. Jonsson and H. Ljung. Tonic supraspinal mechanisms influencing the intestino‐intestinal inhibitory reflex. Acta physiol. scand. 1968. 72. 200–204.

Supraspinal control mechanisms acting on the spinal intestino‐intestinal inhibitory reflex have been studied with regard to their possible tonic influence. The experiments which were done on chloralose or chloralose‐urethane anesthetized, vagotomized cats involved acute experimental lesions at the mesencephalic and cervical spinal levels of the CNS. The results indicate that the autonomic reflex is subjected to facilitation from suprabulbar areas and to strong tonic suppression from bulbar structures.
On the Components of the Kr85Wash‐Out Curves from the Small Intestine of the Cat
Authors: Kampp Mogens , Lundgren Ove , Sjöstrand Johan
Published: December 2008

The wash‐out of intra‐arterially injected Kr35from denervated small intestinal segments (mainly jejunum) of the cat was recorded by means of a scintillation detector at various levels of vascular tone. The elimination curve could be resolved into four components (I‐IV) at all blood flow levels. Four independent methods were used in an attempt to localize the different componerits, namely, registration of the elimination of β‐activity, local injections into different parts of the intestinal segment, autoradiography and comparisons of weights of the compartments. The following localization of the four components was made probable. The first component reflected predominantly a countercurrent exchange of krypton between the ascending and descending limbs of the vascular loops in the mucosa at “resting” flow levels. During vasodilatation, this component mirrored mainly the wash‐out of the tracer from a well‐perfused region in the mucosa‐submucosa. The second and third components mainly reflected the disappearance of Kr85from the mucosa and the muscularis, respectively. The slowest component (IV) probably mirrored an elimination of Kr85from the perivascular fat of the mesentery and an absorption of the tracer from the intestinal lumen.
Aortic Baroreceptor Activity in Normal and Hypertensive Rabbits
Authors: Aars Harald
Published: December 2008

The baroreceptor activity in the entire left aortic nerve was recorded in 9 normal and 5 hypertensive rabbits. A technique based on rectification and integration of the nerve potentials allowed separate analysis of the mean, systolic and diastolic activities. The nervous activities measured at different diastolic blood pressures showed only small variations during recordings over several hours. and small inter‐individual variations. In hypertensive rabbits, the receptors required a higher pressure to start firing than in normal rabbits. The activity was lower at all pressures in hypertensive animals. The difference from normal rabbits increased with increasing pressure, and was most pronounced for the systolic part of the firing. Mechanisms for causing the resetting of baroreceptor activity in hypertension are discussed. It is concluded that a combination of hypertensive wall changes and exhaustion or destruction of some receptors is probably responsible for the resetting.
The Distribution of Fatty Acids between Serum Albumin and Red Cell Ghosts
Authors: Göransson Göran
Published: December 2008

The chemical composition of red cell ghosts are reported. Incubations with red cell ghosts and labeled fatty acids bound to albumin have been carried out. The results show that long and saturated acids are bound to a greater extent to the cell membranes than short and un‐saturated acids. With an increasing mole ratio fatty acids/albumin an increasing percentage of oleic acid was transfered to the cell membranes. It is pointed out that this same tendency was noted earlier in experiments with serum, lipo‐proteins and fatty acids bound to albumin.
A Study of the Muscle Activity and Blood Flow in the Muscles of the Upper Arm in Supporting Heavy Loads
Authors: Carlsöö Sven , Guharay A. R.
Published: December 2008

A fairly heavy load can be held in the arm without any muscular activity and also without an increase in muscle temperature. However, when voluntary effort is used to bring the muscles into activity, the temperature increased gradually. The importance of “passive tissues” in such type of work has been stressed.
Glucose Metabolism and Response to Insulin of Isolated Fat Cells and Epididymal Fat Pads
Authors: Gliemann Jørgen
Published: December 2008

The glucose uptake and the conversion of glucose 1‐14C to 14C‐carbon dioxide and 14C‐tri‐glyceride by epiclidymal fat pads and fat cells isolated after treatment with collagenase was studied with varying concentrations of glucose in the incubation medium. The isolated fat cells took up and metabolized slightly more glucose than the fat pads at a low concentration (0.1 mglml) but seveial fold more than the fat pads at a high concentration (1.6 mg/ml). In the presence of insulin, the isolated cells took up and metabolized 2–3 times more glucose than the fat pads at the low medium glucose concentration and about the same as the fat pads at the high medium glucose concentration. The isolated cells were about 10 times more sensitive to insulin than the fat pads. The isolated cells responded to a concentration of 1.25 μU of insulin per ml and a maximal effect was obtained with a concentration of 20 μU per ml. The equivalent figures for the epididymal fat pads were about 10 μU per ml and 320 μU per ml. Isolated fat cells, preincubated with insulin (100 μU/ml) and then washed, were stimulated for 15–30 min whereas epididymal fat pads, similarly preincubated with insulin (1,000 pU/ ml) and washed remained fully stimulated throughout a 2 hr incubation period. The differences in glucose metabolism of isolated fat cells and epididymal fat pads could be partially explained by a limitation of the glucose diffusion into the fat pad. In addition, the isolated cells seemed more permeable to glucose than fat cells of the “intact” tissue.
Effects of Gastrin and Histamine on Vagally Induced Acid and Pepsin Secretion in Antrectomized Dogs*
Authors: Olbe Lars , Ridley Peter T. , Uvnäs Börje
Published: December 2008

The acid and pepsin responses to sham feeding were studied in 3 Pavlov pouch dogs in which the gastrin releasing regions had been removed. A threshold dose of gastrin extract or histamine for acid secretion potentiated the acid sham feeding response but did not alter the pepsin sham feeding response. Suprathreshold doses of either agent had an additive effect on the potentiated acid sham feeding response but siynificantly inhibited the pepsin sham freding: response.
Monosynaptic Excitation of Alpha Motoneurones from Supraspinal Structures in the Cat
Authors: Lund S. , Pompeiano O.
Published: December 2008

The origin of descending fibres evoking monosynaptic excitatory postsynaptic potentials (EPSPs) in motoneurones was studied.Lumbar flexor and extensor motoneurones were recorded from intracellularly.The ipsilateral ventral and lateral funicles were stimulated at thoracic level in cats with and without chronic lesions of the ipsilateral cervical cord or vestibular complex.In other experiments the ipsilateral Deiters' nucleus was stimulated.Valleys in decending ipsilateral fibres evoke a monosynaptic EPSP in the majority of the flexor and extensor motoneurones with an amplitude corresponding to about 25 per cent of the homonymous group Ia EPSP.The effect is almost entirely of supraspinal origin.Most extensor motoneurones receive this action from fibres originating in the ipsilateral Deiters' nucleus.Flexor, and probably some species of extensor motoneurones, receive the action from a supraspinal structure outside the ipsilateral vestibular complex.The results are discussed in relation to the cerebellar influence on the Deiters' nucleus and the cerebellar inhibition of extensor rigidity.
The Secretion of Sodium and Potassium in Cat Submandibular Saliva during the First Period after Start of Stimulation
Authors: Petersen Ole Holger , Poulsen Jørgen Hedemark
Published: December 2008

In a previous publication the existence of a positive sodium rest transient in the cat submandibular saliva was shown.This sodium transient was greater and had a longer duration than the well known positive potassium rest transient.In the present work a negative potassium transient, succeeding the positive potassium transient and in many respects being closely linked to the positive sodium transient, has been demonstrated.This negative potassium transient, as well as the positive potassium transient, is also reflected in the venous outflow from the gland.
Cardiac Rhythm during Breath‐Holding and Water Immersion in Man
Authors: Paulev Poul‐Erik
Published: December 2008

A report is given of the pulse alterations in 30 subjects during face immersion with and without apnea.The breath was held after one mamixal inspiration, at a transmural, thoracic pressure of zero to +5 mm Hg.Apnea in itself produced a decrease in pulse averaging 9 per cent of the control pulse (mean: 75pLS.E.2.2 beats/min).Apnea plus immersion of the face in 15d̀ C water produced a 14 per cent fall, and face immersion in 15d̀ C water without apnea produced a 7 per cent fall.—In 11 supine subjects the pulse response during apnea was found to be a function of the transmural, thoracic pressure, with little difference between the response in air and in 36d̀ C water.—Both the bradycardia provoked by apnea plus face immersion and that provoked by apnea during whole body immersion is temperature dependent.It is concluded that the bradycardia observed during apneic diving in man, originates from two independent factors.One of these is an ‘apnea bradycardia’ elicited from the intrathoracic, high pressure baroreceptors, and the other is a bradycardia elicited by cold stimulation of the skin.Thus, the validity of Irvings concept of a general vertebrate diving reflex (with unknown receptors) common to animals and man, seems dubious.
The Effect of Oxygen Breathing at Atmospheric Pressure on the Metabolism of Glycerol and Ethanol in Cats.
Authors: Larsen Jens Anker
Published: December 2008

It was found that breathing of oxygen may depress the elimination rate of glycerol in chloralose anesthetized cats.but the depressive effect was highly dependent on the simultaneous metabolism of ethanol.When glycerol and ethanol were infused together, the addition of glycinc increased the elimination rate of glycerol.This increase was inhibited by oxygen breathing.A similar although less pronounced change was seen in the metabolism of ethanol.The results suggest that the effect of oxygen breathing may be explained by inhibition of dehydrogenases responsible for the oxidation of ethanol and by inhibition of the production of adenosine‐5‐triphosphate.