bluuebunny/crossref_metadata_2025 huggingface dataset:
Absence of Monoamines in Olivo‐Cochlear Fibres in Cat
Authors: FEX JÖRGEN , FUXE KJELL , LENNERSTRAND GUNNAR
Published: December 2008

Fex. J., K. Fuxe and G. Lennerstrand,Absence of monoamines in olivo‐cochlear fibres in cat. Acta physiol. scand. 1965.64. 259–262. – The olivo‐cochlear neurons in the cat have been studied with the help of the fluorescence method of Falck and Hillarp with or without crushing of their axons in the vestibulo‐cochlear anastomosis or in the pons. No monoamines were found in these neurons (cell bodies, axons, terminals), not even after axotomy. It is concluded that primary catecholamines and 5‐hydroxytryptamine in all probability do not act as transmitters in the efferent innervation of the organ of Corti.
Studies on the Elimination of Exogenous Lipids from the Blood Stream The Kinetics of the Elimination of a Fat Emulsion Studied by Single Injection Technique in Man
Authors: HALLBERG DAG
Published: December 2008

Hallberg, D. Studies on the elimination of exogenous lipids from the blood stream. The kinetics of the elimination of a fat emulsion studied by single injection technique in man. Acta physiol. scand. 1965. 64, 306–313. – The kinetics of the elimination of a fat emulsion (Intralipid®) from the blood stream was studied after single injections to 10 fasting individuals. Plasma triglycerides (TG) were fractionated by means of polyvinylpyrrolidone density gradients into three fractions. The emulsion TG was found in the top fraction of the gradient and endogenous plasma TG separated into two fractions which were found in the lower part of the density gradient. The kinetics of the emulsion TG fraction were composed of a zero order elimination rate at high TG concentrations and a first order elimination rate at low TG concentrations. Intra‐individual variations were only observed in the zero order part of the kinetics; the possible causes of these variations are discussed. Changes in concentration of the lipids found in the lower part of the density gradient were observed during the elimination of the emulsion TG from the circulation. The possibility that the kinetic principle for one of these fractions (middle fraction) is the same as that for the fat emulsion is discussed.
Cardiovascular and Metabolic Response to Infusions of Prostaglandin E1 and to Simultaneous Infusions of Noradrenaline and Prostaglandin E1 in Man Prostaglandin and related factors 35
Authors: BERGSTRÖM SUNE , CARLSON LARS A. , EKELUND LARS‐GÖRAN , ORÖ LARS
Published: December 2008

Bergström, S., L. A. Carlson, L. G. Ekelund and L. Orö. Cardiovascular and metabolic response to infusions of prostaglandin E1 and to simultaneous infusions of noradrenaline and prostaglandin E1 in man. Acta physiol. scand. 1965. 64. 332–339. – Prostaglandin E1 (PGE1) was infused at a rate of 0.1–0.2 μg/kg/min into 3 healthy, fasting male subjects for 20 min. No consistent changes in arterial pressures occurred. The heart rate increased about 20 beats/min. The concentration of free fatty acids (FFA) and of glycerol in plasma increased. A slight increase in oxygen consumption was observed. PGE1 infused simultaneously with noradrenaline to 2 healthy, fasting male subjects reduced the increase in arterial pressures seen when only noradrenaline was infused to these subjects. Furthermore, PGE1 completely inhibited the noradrenaline induced bradycardia. The increase in the concentration of FFA and glycerol in plasma caused by noradrenaline was only slightly reduced by PGE1. PGE1 had no effect on the calorigenic effect of noradrenaline.
Potassium Induced Release of Transmitter at the Human Neuromuscular Junction
Authors: ELMQVIST DAN
Published: December 2008

Elmqvist, D. Potassium induced release of transmitter at the human neuromuscular junction. Acta physiol. scand. 1965. 64. 340–344. – When the release of ACh quanta from the human intercostal motor nerve terminals, recorded as miniature end‐plate potentials (m. e. p. p. s), was enhanced by raising the potassium ion concentration, the increased rates were only sustained if release rates were limited to not more than 150 m. e. p. p. s/sec either by not using higher concentrations of KCl than 30 mM, or by reducing release with increased magnesium and lowered calcium concentrations when higher potassium ion concentrations were used. If higher rates of release were allowed to occur in the presence of 40 or 50 mM KCl, the release rates subsequently declined to very low levels. The total number of quanta released by 40 or 50 mM KCl corresponded to the amount of ACh estimated to be present in the motor nerve terminals.
Effect of Cortisone on the Hydroxyproline in the Serum and Urine of Young Rats
Authors: KIVIRIKKO KARI I. , LAITINEN OSSI
Published: December 2008

Kivirikko, K. I. and O. Laitinen. Effect of cortisone on the hydroxyproline in the serum and urine of young rats. Acta physiol. scand. 1965. 64. 356–360. –The effect of cortisone on the metabolism of collagen was studied by analysing the concentration of free hydroxyproline in the serum and the excretion of free and total hydroxyproline in the urine of 2‐ and 7‐month‐old rats. The younger rats, weighing 150 g at the beginning of the experiment, received 3 mg and the older rats, weighing 310 g at the beginning of the experiment, 6 mg of cortisone acetate daily. In the 2‐month‐old rats the concentration of free hydroxyproline in the serum and the excretion of free and total hydroxyproline in the urine decreased significantly after the administration of cortisone. By contrast, in the 7‐month‐old rats, which had considerably lower basal values than the 2‐month‐old rats, no changes or only very slight decreases were observed after the administration of cortisone. It is suggested that the decrease in the values observed after the administration of cortisone was due to a decreased content of soluble collagen fractions in the tissues. Probably the smallness of the changes in the 7‐month‐old rats was because a considerably smaller proportion of the hydroxyproline in the serum and urine of these older rats was derived from soluble collagen fractions.
The Permeability of Brain Capillaries to Non‐Electrolytes
Authors: CRONE CHRISTIAN
Published: December 2008

Crone, C.The permeability of brain capillaries to non‐electrolytes. Acta physiol. scand. 1965.64. 407–417. – By means of the“Indicator diffusion” method blood‐brain barrier permeability characteristics were studied on dogs. The permeability coefficient of fructose, glycerol, propylene glycol, urea, thiourea, antipyrine, ethanol, propanol and butanol was calculated. If these substances are ordered according to their rate of passage from blood into brain tissue a hierarchy is found which corresponds to that which is typical of the permeability of cell membranes to non‐electrolytes. The experiments lend support to the view advanced by the late August Krogh that the permeability characteristics of the blood‐brain barrier are analogous to those of cell membranes in general. This conclusion is discussed against the background of recent findings of morphologically‐demonstrated tightness of cerebral capillaries which imply that material which diffuses from blood into brain tissue must pass the plasma membranes of the endothelial cells.
High‐Frequency Repetitive Firing of Cat Lumbosacral Motoneurones Stimulated by Long‐Lasting Injected Currents
Authors: Kernell Daniel
Published: December 2008

Kernell, D. High‐frequency repetitive firing of cat lumbosacral motoneurones stimulated by long‐lasting injected currents. Acta physiol. scand. 1965. 65. 74–86. Repetitive discharges were initiated in motoneurones by steady currents injected through an intracellular micro‐electrode. At weaker currents, producing firing rates up to on the average 51 (30–84) imp/sec, the steady discharge frequency was approximately linearly related to current strength (cf. Granit, Kernell and Shortess 1963 a). Several cells were capable of setting up steady discharges only within this so‐called “primary” range. In many other cells, steady repetitive firing was obtained even with stronger currents. There were in the latter two ranges of steady firing, the primary one referring to weak and a “secondary” referring to stronger stimulating currents, each approximately fitted by a separate straight line in the graphs relating impulse frequency to current strength. The straight line wich referred to steady firing within the secondary range had a 2–6 times steeper slope than the one characterizing the primary range. Motoneurones capable of maintained firing within the secondary range could reach steady firing rates of the order of 125 (88–195) imp/sec. The maximal impulse frequency within the primary range was about the same initially in the discharge as later on. The findings are discussed also with regard to the repetitive firing of reflexly activated motoneurones.
Analysis of the Efflux Kinetics of Sodium from Small Cylinders of Rabbit Kidney Cortex
Authors: Bojesen E. , Leyssac P. P. , Nielsen B. Svejgaard
Published: December 2008

Bojesen, E., P. P. Leyssac and B. S. Nielsen. Analysis of the efflux kinetics of sodium from small cylinders of rabbit kidney cortex. Acta physiol. scand. 1965. 65. 105–119. —Based upon two different two‐compartment models, a non‐communicating and a more realistic communicating two‐compartment system, the efflux curves from two cortical cylinders of rabbit kidney were sub‐ected to a graphical and a numerical analysis respectively. A fairly good correspondance was obtained between the results of both types of analysis and a surprisingly good fit with the experimental data was obtained by the numerical analysis. The results of the latter analysis showed that in the cylinders 85% and 80% of the exchangeable sodium was in diffusion equilibrium with the medium. The “diffusion coefficient” was calculated to be 7.3 × 10‐6 cm2 sec‐1 at 25°C and 13 × 10‐6 cm2. sec‐1 at 40°C. From separate determinations of the average concentration of exchangeable sodium in tissue water in a serie of cylinders of similar dimensions as those used for the analysis of the efflux curves, it was calculated that the fraction of exchangeable sodium, which is not in diffusion equilibrium with the medium (15–20 %), occupied a fraction of the tissue water of 30–45 % at a sodium concentration of about 55–40 meq/l. Taking an area to volume ratio corresponding to a single proximal tubule, a flux rate was calculated and found to be of an order of 10–100 times greater than that obtained in striated muscles by different investigators.
Studies on Some Systems of Adrenergic Synaptic Terminals in the Abdominal Ganglia of the Cat
Authors: Hamberger Bertil , Norberg Karl‐Axel
Published: December 2008

Hamberger, B. and K.‐A. Norberg.Studies on some systems of adrenergic synafhc teminals in the abdominal ganglia of the cat. Acta physiol. scand. 1965.65. 235–242. — The course of adrenergic fibres forming synaptic structures in certain visceral ganglia of the cat has been studied with the histochemical fluorescence method of Falck and Hillarp, after selective denervation. The adrenergic synaptic terminals in the intramural ganglia of the colon have their cell bodies in the inferior mesenteric ganglia. The same holds for most of the adrenergic muscle innervation in the bladder trigonum. The adrenergic synaptic terminals in the intramural ganglia of the bladder originate mainly in cell bodies in these or other pelvic ganglia. Adrenergic vasomotor nerves reach the bladder via the pelvic nerves. The adrenergic synaptic terminals in the inferior mesenteric ganglia are mainly of intraganglionic origin. These terminals seem to constitute important and widespread systems for the modulation of ganglionic impulse transmission.
The Action of Adrenaline in Cardiac Muscle Dissociation between Phosphorylase Activation and Inotropic Response
Authors: ØYe Ivar
Published: December 2008

Øye, I.The action of adrenaline in cardiac muscle. Dissociation between phosphorylase activation and inotropic response. Acta physiol. scand. 1965.65. 251–258. — Isolated, working rat hearts were used in order to study the relationship between phosphorylase activation and inotropic response after adrenaline administration. At the maximum of inotropic response a small but consistent activation of phosphorylase was found (19.2 per cent of the total activity present in the a form, versus 5.0 per cent in the controls). A lag of about 20 sec separated the time of onset of phosphorylase activation from the time of onset of the inotropic response, phosphorylase activation being the later of the two changes and therefore unlikely to play a part in the chain of events leading to increased force of contraction. In the early phase of the inotropic response no activation of phosphorylase was found when the tissue was extracted in glycerol at 30° C. However, an activation of phosphorylase was revealed in these hearts when aqueous extraction at room temperature was carried out. Most likely this finding reflects an activation of phosphorylase b kinase during the early phase of the inotropic response. The results imply that phosphorylase activation and inotropic response might be triggered by the same initial event, in spite of the dissociation, which has been observed between these two adrenergic effects.
Thyroidectomy of the Goat
Authors: Ekman Lars
Published: December 2008

Ekman, L. Thyroidectomy of the goat. Acta physiol. scand. 1965. 65. 331–336. —A procedure to obtain complete thyroidectomy in the adult goat is described. In 4 of 6 goats ectopic thyroid tissue was detected after surgical thyroidectomy. The goats were given treatment doses of 20 to 25 mCi I131 once a month until no ectopic thyroid tissue could be detected by external radioactivity measurements. An additional dose of 25 mCi I131 was given after the first negative radioisotope scanning. The development of hypothyroidism was followed by estimations of plasma protein‐bound radioiodine (PBP and PBI131) and total serum protein‐bound iodine (PBI). Three doses of 25 mCi I131' administered once a month to two pregnant goats caused a complete ablation of the thyroid glands in the offspring. With the exception of a complete lack of thyroid tissue the kids were apparently normally developed, but were borne dead. After delivery a very marked reduction in milk production was noted. The amounts of colostrum milk, however, seemed to be normal. The adult goats increased in weight following the combined thyroidectomy procedures, and showed certain changes in temperature regulation. Otherwise no clinical manifestations of hypothyroidism were detected during the seven month period the animals were under observation.
The Tactile Hairs on the Cat's Foreleg
Authors: Nilsson Bengt Y. , Skoglund C. R.
Published: December 2008

Nilsson, B. Y. and C. R. Skoglund. The tactile hairs on the calls foreleg. Acta physiol. scand. 1965. 65. 364–3369, ‐ The vibrissae‐like hairs at the wrist of the cat's foreleg have been studied morphologically and physiologically. Each hair follicle contains a large blood sinus close to which a number of Pacinian corpuscles are situated. Recording from nerve filaments showed most nerve endings to be spontaneously active. Bending of a hair resulted in an increased discharge frequency. up to 250 per sec. rapidly declining to a steady frequency level of 20–40 per sec which was maintained without appreciable further decline during several minutes. Bending in the opposite direction might cause cessation of the spontaneous discharge but otherwise no pronounced directional sensitivity was observed. Releasing the hair was usually followed by a silent period in the spontaneous discharge. Contrasting with the slowly adapting discharges of the hair endings are the transient responses of the Pacinian corpuscles with characteristically low threshold to vibratory stimulation. The significance of the blood sinus and of the closely related Pacinian bodies is briefly discussed.
Regional Blood Flow in the Cerebral Cortex, Measured Simultaneously by Heat and Inert Gas Clearance
Authors: Betz E. , Ingvar D. H. , Lassen N. A. , Schmahl F. W.
Published: December 2008

Regional blood flow of the cerebral cortex was measured simultaneously with two methods, one being a modification of the discontinuous 85Krypton clearance method, the other a continuous heat‐clearance method. A correlation could be established between the regional cortical blood flow values obtained with the two methods. It is concluded that the heat‐clearance method can be calibrated by the 85Krypton method, and that, hence, a combined use of the two methods may be helpful for a quantitative analysis of rapid and transient changes in regional cortical blood flow.
Cellular Localization of Monoamine Oxidase in Rat Salivary Glands
Authors: Almgren Olle , Andén Nils‐Erik , Jonason Jan , Norbero Karl‐Axel , Olson Lars
Published: December 2008

After ligation of the excretory ducts and subsequent atrophy of the parenchymal cells of the rat sub‐maxillary and sublingual glands, a severe reduction of the MAO activity was demonstrated both biochemically (more than 60 per cent decrease expressed as activity per gland) and histochemically. Chronic postganglionic sympathectomy produced a much smaller diminution of the MAO activity in these glands. It is concluded that the major part of the MAO in rat salivary glands occurs in the parenchymal cells.
Testing for Doubly Innervated Fibers in the Intrinsic Laryngeal Muscles of the Dog
Authors: Mårtensson A.
Published: December 2008

Experiments were performed on the cricothyroid and thyroarytenoid muscles of anesthetized dogs with the object of searching for evidence indicating polyneuronal innervation of single muscle fibers. The cricothyroid which is supplied by two peripheral nerves was tested in three different types of experiment, viz. (1) by applying tetanic stimulation to both nerves to find out whether the tension developed on simultaneous stimulation showed a “deficit” as compared to the sum of the tensions produced on stimulating each nerve alone; (2) by applying a single stimulus to each nerve to find out whether the peak tension rose when the stimulus interval was increased from zero to intervals sufficient for elicitation of a double twitch in any fibers supplied by both nerves; (3) by applying subtetanic stimulation of identical frequencies to both nerves to find out whether the contraction curves thus obtained had the same amplitude when corresponding shocks were applied in phase and sufficiently out of phase to permit any fibers supplied by both nerves to increase their discharge frequency and their tension development. The three types of experiment failed to provide any conclusive evidence for doubly innervated fibers in the cricothyroid. In the thyroarytenoid which is supplied by only one peripheral nerve the two latter types of experiment were made possible by a special experimental arrangement; however, no definite evidence for polyneuronal innervation was obtained. The conclusion was drawn that polyneuronal innervation does not occur on a significant scale in the muscles studied even though its existence on a small scale cannot be definitely excluded in view of the possible sources of error involved.
Concomitant Adrenergic and Parasympathetic Fibres in the Rat Iris
Authors: Ehinger B. , Falck B.
Published: December 2008

A nerve net containing both acetylcholinesterase (AChE) and non‐specific cholinesterases (ChE) was demonstrated together with a corresponding adrenergic nerve net in the dilator region of the rat iris with a specially developed combination of the techniques for showing cholinesterases and adrenergic nerves. There is no such correspondence between adrenergic nerve fibres and AChE‐containing fibres of the iridic vessels, indicating a purely sympathetic innervation of them. Only AChE‐con taining fibres of the dilator region disappear appreciably upon chronic parasympathetic denervation. Chronic sympathetic denervation does not affect the cholinesterase‐staining properties. The presence of a nerve net in the dilator region, not degenerating upon sympathectomy and the purely sympathetic innervation of the iridic vessels was corroborated with methylene blue stainings. Thus, adrenergic (sympathetic) and AChE‐containing (mainly parasympathetic) fibres run closely together in the vegetative network of the dilator region, but the two types of fibres may also occur separately. It has as yet not been possible to identify the structure affected by the parasympathetic fibres in the dilator region.
Changes of Nucleoside Phosphatase Activity in the Hypoglossal Nucleus during Nerve Regeneration
Authors: Sjöstrand Johan
Published: December 2008

The effect of nerve crush on the activity of nucleoside di‐and triphosphatases was studied in the hypoglossal nucleus of the albino rabbit with histochemical methods. Activity of nucleoside phosphatases was found in microglial cells. Golgi apparatus of the neurons and vascular walls. During nerve regeneration an increase in enzyme activity was observed in the microglial cells as well as an increase in the number of microglial cells. The Golgi apparatus of the regenerating neurons showed an initial decrease followed by increase in nucleoside phosphatase activity. After the first week an increase in capillarization and capillary enzyme activity could be demonstrated. The findings are discussed and an increased participation in uptake and transport during nerve regeneration is suggested for the cellular structures demonstrating nucleoside phosphatases.
A Quantitative Study on the Nigro‐Neostriatal Dopamine Neuron System in the Rat
Authors: Andén Nils‐Erik , Fuxe Kjell , Hamberoer Bertil , Hökfelt Tomas
Published: December 2008

In a combined biochemical and histochemical investigation the following quantitative data on a unilateral nigro‐neostriatal dopamine neuron system in the rat have been obtained or calculated. — The number of neurons is 3,500 on the average. — There are about 120 pg dopamine per neuron (1 pg = 10‐12 g). — The terminals contain 50 (or 150) times more dopamine than the cell bodies. —The terminal system of one neuron varies mainly between 55 and 77 cm in length and contains about 500,000 varicosities. — The neostriatum, with a volume of 33 mm3, contains 109 dopamine varicosities occupying 0.3 % of the volume, and 4,000,000 nerve cell bodies (not containing dopamine). — One average dopamine varicosity, with a diameter of 0.4 μ, contains 2.5 × 10‐4 pg dopamine, and has a dopamine concentration around 8,000 μg/g. — One dopamine cell body of the substantia nigra, with a mean diameter of 30 μ, contains 2.5 (or 0.8) pg dopamine, and has a dopamine concentration around 200 (or 60) μg/g.
The Effect of Nerve Activity on the Depletion of the Adrenergic Transmitter by Inhibitors of Noradrenaline Synthesis1
Authors: Corrodi H. , Malmfors T.
Published: December 2008

When rats and mice are treated with an inhibitor of noradrenaline (NA) synthesis (H 44/68, the methylester hydrochloride of dl‐α‐methyltyrosine) there is a reduction in the NA content in sympathetically innervated organs such as the heart and the submandibular glands. In the present investigation the mechanism behind this depletion has been examined by biochemical methods and with the histochemical fluorescence method of Falck and Hillarp. If the nerve impulse flow in the adrenergic nerves is reduced to a minimum by cutting the preganglionic trunk, the decrease in the transmitter content is reduced both in the iris and the submandibular gland. This shows that the nerve impulse flow in intact nerves is the main cause of the depletion of NA after treatment with an inhibitor of NA synthesis. When mice and rats are exposed to cold (3°C) after treatment with H 44/68 there is a significantly greater reduction in the NA content of the heart than when the animals are kept at room temperature (22°C) after the same treatment. This indicates that there is an increased nerve impulse flow in the adrenergic nerves of the heart in the animals exposed to cold stress. Uptake of adrenaline in the heart may also indicate an increase in activity in the adrenal medulla of these animals. There is good correlation between the biochemical and histochemical findings but the latter indicate that there is a greater reduction in the adrenergic nerves of the iris than in the nerves of the submandibular gland.

The investigation shows that inhibitors of NA synthesis are very useful in functional studies of the adrenergic nerves.
Effect of Cervical Sympathetic Stimulation on Accommodation in Monkeys An example of a beta‐adrenergic, inhibitory effect
Authors: Törnqvist Goran
Published: December 2008

The preganglionic cervical sympathetic nerve, of mainly cynomolgus monkeys (Macaca irus), has been stimulated electrically using different stimulation rates. The accommodative response to stimulation was a change in refraction towards hypermetropia. This response could not be inhibited by adrenergic α‐receptor antagonists, though these drugs reduced the blood volume changes in the eye upon stimulation. On the other hand, the β‐adrenergic blocker propranolol caused a complete elimination of the sympathetic stimulation response, though changes in eye volume seemed uninfluenced. The accommodative response (in diopters) to stimulation increased considerably when the eye was under strong cholinergic tone. When the animal was pretreated with a large dose of atropine. cervical sympathetic stimulation did not affect the refractive state of eye. The results indicate the presence of a β‐adrenergic, inhibitory mechanism of the ciliary muscle. Possibly this mechanism is responsible for distance accommodation (decrease in accommodation). Changes in vascular structures upon sympathetic stimulation play no practical part in regulating the accommodation.
The Effect of DOPA on the Spinal Cord. 1. Influence on Transmission from Primary Aflerents
Authors: Andén N.‐E. , Jukes M. G. M. , Lundberg A. , Vyklicky L.
Published: December 2008

In unanesthetized spinal cats an i.v. injection of DOPA depresses transmission of short latency effects from the flexor reflex afferents (FRA), including transmission of excitatory and inhibitory action to motoneurones and ascending pathways as well as transmission to primary afferent terminals. The depression resembles that of the decerebrate preparation. After DOPA the flexor reflex evoked by natural stimulation of the skin is increased. This increase is due to a long latency, long lasting discharge in flexor motoneurones evoked by repetitive activity in the FRA. The late discharge is accompanied by a late wave of depolarization in the dorsal roots. These events are due to long lasting activity in the spinal cord and do not depend upon a peripheral loop. The selective action of DOPA shows that its action on transmission in the spinal cord is not secondary to circulatory changes. The working hypothesis is forwarded that DOPA inhibits transmission of short latency effects from the FRA through liberation of transmitter from a descending noradrenergic pathway.
The Effect of DOPA on the Spinal Cord. 2.APharmacological Analysis
Authors: Andén N.‐E. , Jukes M. G. M. , Lundberg A.
Published: December 2008

Drugs known to influence noradrenergic transmission were investigated with respect to their action on the effect of DOPA on transmission in the spinal cord. The effect of DOPA may be prevented by inhibition of DOPA decarboxylase and by pretreatment with reserpine, it is enhanced by inhibition of monoamine oxidase and reversed by the adrenergic α‐receptor blockers phenoxy‐benzamine and chlorpromazine; the β‐receptor blocker nethalide does not reverse it. The effect of DOPA is reduced in the chronic spinal preparation. These data show that DOPA acts by liberation of catecholamines (dopamine or noradrenaline) in the spinal cord. It is suggested that DOPA increases the synthesis and liberation of transmitter from the terminals of a descending noradrenergic pathway.
The Effect of Imipramine and Related Antidepressive Drugs on Estrus Behaviour in Ovariectomised Rats Activated by Progesterone, Reserpine or Tetrabenazine in Combination with Estrogen
Authors: Meyerson Bengt J.
Published: December 2008

The effects of antidepressive drugs were studied on estrus behaviour activated in ovariectomised rats by progesterone, tetrabenazine or reserpine in combination with estrogen. On tetrabenazine‐ activated estrus behaviour an inhibitory effect was obtained by imipramine, desmethylimipramine, amitriptyline and nortriptyline, but not by trimeprimine. All the mentioned antidepressive compounds reduced the progesterone activated heat response; however, trimeprimine and nortriptyline were effective only when comparatively high doses were used and furthermore the effect was short‐lasting. Reserpine‐activated estrus behaviour was inhibited by imipramine; other drugs were not tested. Imipramine and the monoamine oxidase inhibitors pargyline and nialamide acted synergistically in inhibiting progesterone‐activated estrus behaviour. There was no relation between the inhibitory effect on tetrabenazine activated estrus behaviour and the ability of the different antidepressant drugs to prevent tetrabenazine induced sedation or to induce hyperactivity (compulsive exploring behaviour). The present data further support the earlier suggestion that there exist serotoninergic pathways mediating inhibition of estrus behaviour. It seems that the antidepressive compounds studied potentiate central serotoninergic mechanisms.
Release of3H‐Metaraminol by Different Mechanisms1
Authors: Carlsson Arvid , Waldeck Bertil
Published: December 2008

Mice were given3H‐metaraminol i.v. After 15 min, when the uptake by the adrenergic nerve fibres had been almost completed, various drugs were given and their ability to release the amine was investigated. Protriptyline and chlorprothixene, which block the amine‐concentrating mechanism at the level of the cell membrane, caused a clearcut release of3H‐metaraminol. This was true also of reserpine and prenylamine, which block the amine‐storage mechanism of the granules. Combination of the two types of agents caused a much more rapid release than either type alone. Guanethidine appeared to possess both types of action. After pretreatment with reserpine3H‐metaraminol could still be taken up but was rapidly released by desipramine, which blocks the concentrating mechanism at the level of the cell membrane, and by analogues of the adrenergic transmitter,e.g.tyramine, metaraminol, and amphetamine. Monoamine‐oxidase inhibitors were found to release3H‐metaraminol. It is suggested that this release is mediated by monoamines accumulating in the adrenergic nerve fibers.
Studies on the Mechanism for the Calorigenic Effect of Adrenaline in Man
Authors: Svedmyr Nils
Published: December 2008

Adrenaline infusion in man increased the oxygen consumption and the lactate, FFA and glucose concentrations in the blood. When the FFA‐mobilizing effect of adrenaline was blocked selectively with nicotinic acid the calorigenic effect was reduced by 29%. When L(+)lactate was infused in such a dose that the blood lactate concentration rose to the same level as after the adrenaline infusion, the oxygen consumption increased, this increase being 35% of the total increase induced by the adrenaline infusion. An increase in both lactate and FFA metabolism is therefore assumed to be of importance for the calorigenic effect of adrenaline in man. The possibility that adrenaline stimulates both a lactate and a FFA cycle is discussed. The importance of other mechanisms for the calorigenic effect such as the heart‐stimulating and hyperglycemic effects of adrenaline is also considered.
Glucose Uptake in Potassium‐Depolarized Mammalian Muscle
Authors: Crone Christian
Published: December 2008

Experiments were performed on perfused cat hind limbs to study whether the uptake of glucose by striated muscle is linked with active transport of ions. The glucose uptake in the control periods was 1.4 μmole/100 g/min. Elevation of the plasma potassium concentration to 25–40 meq/l led to an average glucose uptake of 3.0 μmoles/100 g/min. Addition of strophanthin to a final concentration of 10‐5M strongly depressed glucose uptake, the average value being 0.3 μmole/100 g/min. The oxygen consumption in the strophanthin experiments fell from 7.3 μmoles/100 g/min to 6.9 μmoles/100 g/min. A Na/O‐ratio of 5 was calculated for mammalian muscle. Substitution with potassium‐rich blood after addition of strophanthin eliminated the strophanthin effect on glucose uptake. It is proposed that the mechanism for carrier‐mediated glucose uptake in mammalian muscle may be connected with the mechanism for active transport of either sodium or potassium.
The Effect of Calcium on Potassium Contractures of Single Slow Muscle Fibres of Xenopus Laevis
Authors: Lännergren Jan
Published: December 2008

Isolated slow muscle fibresof Xenopus laeviswere subjectcd to step increases in external potassium concentration at various external calcium concentrations. An increase in [Ca]oshifted the curve relating peak tension to log [K]oto higher K‐koncentrations. a decrease in [Ca]ocaused a shift in the opposite direction. Similar effects were seen on the relation between inactivation and log [K]o+. The peak tension was but little affected by [Ca]o; the time‐course of contractures was altered in such a way that the rate of relaxation was increased in low [Ca]oand decreased in high [Ca]o. Evidence was obtained that the effect of altered [Ca]ooccurs as rapidly as that of altered [K]o. Some observations were also made on contractures in Ca‐free solutions and in solutions with Na partially subatituted bv Ba.
Static and Dynamic Properties of Golgi Tendon Organs in the Anterior Tibial and Soleus Muscles of the Cat
Authors: Alnæs Egil
Published: December 2008

The responses of tendon organs of the anterior tibial muscle have been studied during twitch contraction, passive stretch, fused tetanic contractions and sinusoidal stretching in Nembutal anesthetized cats. The majority of the tendon organs had similar thresholds to active contraction and passive stretch tension. Some tendon organs were found to discharge spontaneously in the relaxed muscle. An approximate power function relationship has been found between steady state impulse frequency and muscle tension. The receptor properties are compared with those of soleus tendon organs. It is concluded that static and dynamic properties of Golgi tendon organs in the anterior tibial and the soleus muscles fall within the same range of variation, and that apparent discharge dissimilarities can be explained as due to differences in muscle mechanics.
Renal Clearances and Urinary Sodium and Potassium Excretion during Supine Exercise in Normal Subjects
Authors: Castenfors Jan
Published: December 2008

Clearance of inulin (Cin) and para‐aminohippuric acid(cpah). free water clearance(ch2o)and urinary excretion of sodium and potassium during exercise were studied in 14 healthy male subjects. The exercise was performed on a bicycle ergometer (mean load 729 kpm/mini in the supine position. Cpahdecreased significantly, but Cinwas not significantly changed. The antidiuresis during and after exercise was principally secondary to decreased Ch2o, indicating ADH release. The urinary sodium excretion and per cent filtrered sodium exereted were significantly decreased during exercise, indicating increased tubular reabsorption of sodium. The findings suggest that the increased tubular reabsorption may in part be due to increased aldosterone excretion during exercise. Urinary potassium excretion was not significantly changed during exercise.
The Interaction of Secretin and Pancreozymin on the External Pancreatic Secretion in Dogs
Authors: Henriksen F. W. , Worning H.
Published: December 2008

The pancreatic secretion of fluid, bicarbonate and protein in 4 dogs with chronic Thomas type fistulae, has been studied in response to secretin (1U/kg b.w.), pancreozymin (1U/kg b.w.) and combined secretin‐pancreozymin (1U/kg b.w. of each). The secretion rates of fluid, bicarbonate and protein after combined, submaximal stimulation were highly reproducible, as indicated by the coefficients of variation 1.7 per cent (fluid), 3.9 per cent (bicarbonate) and 5.1 per cent (protein). The secretion rates of fluid and bicarbonate obtained after the combined stimulation with secretin‐pancreozymin (1U/kg b.w. of each) were very close to those obtained after isolated stimulation with maximal doses of secretin. Secretin and pancreozymin are shown to have a potentiating effect on the pancreatic secretion of bicarbonate, but only an additive effect on the secretion of protein.
Quantitative in Vitro Studies on Noradrenaline Uptake and its Inhibition by Amphetamine, Desipramine and Chlorpromazine
Authors: Häggendal Jan , Hamberger Bertil
Published: December 2008

The accumulation of noradrenaline (NA) was determined biochemically after incubation with NA of slices from the vas deferens, cerebral cortex and neostriatum of rats pretreated with reserpine and nialamide. It was found that both areas rich in NA terminals, such as the vas deferens and cerebral cortex, and areas rich in dopamine (DA) terminals, such as the neostriatum, efficiently accumulated NA. (+)‐Amphetamine effectively inhibited NA accumulation in all the tissues, whereas desipramine inhibited the uptake in areas rich in NA terminals efficiently, but in areas rich in DA terminals only to a slight extent. In this respect, the effect of chlorpromazine was similar to that of desipramine. The data strongly support the view that the reserpine‐resistant accumulation mechanism of the transmitter differs in the two types of catecholamine terminals.
Effects of “Diving” on Cardiac Output in Ducks
Authors: Folkow B. , Nilsson N. J. , Yonce L. R.
Published: December 2008

Arterial and central venous pressures (AP and CVP), cardiac output (CO) and heart rate (HR) were recorded, and stroke volume (SV) computed, in awake ducks before, during and after submersion, special attention being paid to the time course and extent of the induced changes. During rest CO was 1509 ml/min (S.D. 245), HR 244/min (S.D. 83) and SV 6.6 ml (S.D. 1.6). Immediately upon submersion CO and HR fell slightly and then showed a more gradual, up to twenty fold reduction within 1–2 min; SV decreased moderately despite a 10–20 mm Hg increase in CVP. During the immediate 1–2 sec postdive period HR increased to 300–500/min, with a sharp rise in AP while CVP fell. Within 10–15 sec a profound vasodilatation was established, AP and CVP returning towards normal. CO now reached 2500–4000 ml/min and SV increased beyond resting level. Thus, at the shift from submersion to emersion CO could increase up to fiftyfold within 10–15 sec; CO then returned towards control in 6–8 min. Results with vagal and sympathetic blocking agents suggest the following neurogenic events: During submersion inhibited sympathetic activity to the heart is coupled with a greatly intensified vagal discharge. reducing also ventricular contractility; the sympathetic vasoconstrictor fibre discharge is sharply increased. On emersion a complete reversal of this intense and differentiated pattern takes place within 1–2 sec. The receptors and central mechansims involved are briefly discussed.
Response Characteristics of Muscle Spindle Endings at Constant Length to Variations in Fusimotor Activation
Authors: Andersson Bengt F. , Lennerstrand Gunnar , Thoden Uwe
Published: December 2008

The aim of the present investigation was to determine the transfer function between fusimotor stimulus rate and afferent impulse frequency of muscle spindles at constant length. Spindle endings in the external intercostal and in the ankle extensor and flexor muscles of the cat have been subjected to variations in fusimotor stimulation frequency. The variations had sinusoidal form and ranged in repetition rate from 1/4 to 1/12 c/s. Both single‐fibre and double‐fibre stimulations were studied. Linear static and dynamic input‐output relations were found in the stimulus frequency range 60 to 180 pulses/sec. For all combinations of one or two fusimotor fibres to one spindle ending the transfer function had the same general form. The static sensitivities were largest for primary endings under static fusimotor control; about the same sensitivities were obtained in dynamic fusimotor activation of primary endings and in static activation of secondary endings. With regard to dynamic properties all combinations of fusimotor fibres and spindle endings were equivalent. This was further tested with step and triangular wave inputs. Explanations for this similarity are discussed.
5‐Hydroxytryptamine Release from Enterochromaffin Granules in vitro
Authors: Penttilä A. , Saris N.‐E.
Published: December 2008

5‐Hydroxytryptamine (5‐HT) releasein vetrofrom cow and pig enterochromaffin granule preparations was studied. An accelerated 5‐HT release from the granule fraction was caused by: elevation of temperature, freezing and thawing, dilution, increase of the pH of the incubation medium, addition of chlorprornazine, irniprarnine, mepyramine, segontin®, tyramine, trypsin, hydrocorti‐sone and cortisone. In various isotonic salt and buffer solutions the amine release was faster than that in isotonic sucrose solution. A slight 5‐HT release was induced by Ca++ions, Titriplex III®, Titriplex IV® and histamine, and an almost complete release by CuCl2, distilled water and all the detergents studied. Monoamine oxidase inhibitors (in 0.15 M phosphate buffer, pH 6.9) and MgCl2(in 0.3 M sucrose solutions, pH 6.9) were the only chemicals that retarded amine release. The following chemicals had no effect: ACTH, thyroxine, adrenaline, noradrenaline, dihydroxy‐phenylalanine, tryptophan, indoleacetic acid, 3‐hydroxytyramine, acetylcholine or butyrylcholine with eserine, and guanethidine.

The release of 5‐HT from enterochromaffin granules resembles in some ways amine release from platelets, mast cells or granules carrying norepinephrine but differs in others. The special features of the enterochromaffin granules are discussed.
Biliary Bile Acids and Hepatic Ultra‐Structure in Hamsters Fed Gallstone‐inducing and ‐dissolving Diets
Authors: Bergman F. , Linden W. van der , Sjövall J.
Published: December 2008

Bile acids in gallbladder and fistula bile and the hepatic structure were studied in hamsters fed gallstone inducing diets with and without supplementation of cholestyramine or thyroxine. The predominant bile acids identified were cholic, chenodeoxycholic, deoxycholic, 7‐keto‐deoxycholic and 7α, 12α‐dihydroxy‐3‐keto‐5β‐cholanoic acids. Small amounts of 7‐ketolitho‐cholic, 12‐ketolithocholic, 12α‐hydroxy‐3‐keto‐5β‐cholanoic, allocholic and (tentatively) urso‐deoxycholic acids were also found. The mean of the chenodeoxycholic/cholic acid ratios in hamsters fed a diet favouring the formation of cholesterol gallstones was 0.88 and fell to about 0.04 when 3 % cholestyramine was added to the diet. Thyroxine caused a similar but less striking fall of this ratio. The bile acid/cholesterol ratio was lower in animals on the cholesterol stone inducing diet and was increased by cholestyramine administration, which prevented the formation of cholesterol stones. As in previous work, morpho‐histochemical changes were found in the hepatic parenchymal cells almost exclusively of hamsters treated with the thyroxine containing diet which induces predominantly pigmented stones. Electron microscopy showed the cells to contain numerous lipid droplets and clusters of autophagic vacuoles. Possible relationships between biliary bile acids, cholesterol and gallstone formation and the effects of cholestyramine and thyroxine are discussed.
The Influence of Hypoxia on the Spontaneous Thalamic and Cortical Barbiturate Spindles
Authors: Etholm B. , Junge K. , Sveen O.
Published: December 2008

Spontaneous barbiturate spindles in the thalamus and the cortex were recorded in cats anesthetized with barbiturates and subjected to hypoxia. During stagnant hypoxia produced by pharmacological reduction of the blood pressure, there was no spindle activity when the blood pressure was below 60 mm Hg. In hypoxic hypoxia, the spindles disappeared after the oxygen content of the nitrogen‐oxygen mixture had been reduced to 4.5 per cent. In this condition, the blood pressure was always at or above 80 mm Hg and very often above 100 mm Hg. The lack of spindles was probably the result of the combined effect of changes in the blood pressure and the local tissue oxygen level.—Before and after the state of no spindle activity, there was a period of high synchrony characterized by low degree of activity between the spindles and high‐voltage waves within the spindles. Except for the abrupt disappearance and reappearance of the spindles, the degree of synchrony was the only parameter of barbiturate spindle activity that varied during hypoxia.—The results suggest that the mechanism of spindle activity may operate with a relatively small number of cells. A more complex neuronal system with a greater number of synapses may be supposed to be more susceptible to severe degrees of hypoxia.
Inhibitory Action of Adrenergic Blocking Agents on Reuptake and Net Uptake of Noradrenaline in Nerve Granules
Authors: Euler U. S. von , Lishajko F.
Published: December 2008

The effect of various adrenergic blocking agents on the reuptake and net uptake of noradrenaline (NA) in isolated adrenergic nerve granules has been studied. All of the α‐ and β‐blockers tested exerted an inhibitory action on the spontaneous release rate of NA from granules and also on the reuptake of3H‐labelled NA from a medium containing 1–3×10‐6M NA. The highest activity was shown by the α‐blockers dihydroergotamine and Plegicil, but some β‐blockers were almost as active. No significant difference in inhibitory action was observed between the l‐ and d‐isomers of propranolol and Aptin. In the presence of ATP and NA 5 × 10‐6M‐10‐4M, the net uptake of NA in partially depleted granules was strongly inhibited by the same blocking agents as were most active on the reuptake. The present results confirm the previous finding that adrenergic blocking agents, both of the α and β‐type, inhibit NA uptake in nerve granules. The possible mediation of transmitter release and uptake by granule receptors is discussed.
Diamine Oxidase in Blood Plasma in Some Vertebrates and Anodonta cygnea before and after Injection of Heparin
Authors: Hansson Roy , Thysell Hans
Published: December 2008

After intravenous injection of heparin (in aniounts related to the body‐weight) thc blood plasma diamine oxidase(DAO‐) activity increased transiently in all vertebrates studied (cod, frog, fowl, mouse, white rat, golden hamster, guinea‐pig, rabbit, cat, dog, goat, sheep and cow). The DAO‐response to heparin varied strongly between the species. Often with a bi‐phasic ascent, it showed a maximum (within a few minutes to about one hour) and then decreased, often in a “monoexponential” fashion, in the course of the next few hours. In anodons no significant DAO‐activity was found.—The biological significance of the heparin effect upon DAO is discussed with special reference to the coexistence of heparin and histamine in the mast cells.
The Effect of Nerve Stimulation on the Uptake of Noradrenaline into the Adrenergic Nerve Terminals
Authors: Häggendal Jan , Malmfors Torbjörn
Published: December 2008

In rats pretreated with reserpine and nialamide the effect of sympathetic stimulation, 20 and 6 imp/sec, on the uptake of exogenous noradrenaline was studied in the adrenergic nerves of the iris and salivary glands using fluorescence and biochemical methods, respectively. The uptake of noradrenaline was smaller on the stimulated than on the unstimulated side. The results are discussed with respect to factors such as changes in the circulation, transmitter release during the stimulation, and the presence of an intermittent blockade of the membrane pump during the impulses. It is suggested that the latter mechanisms might be of some physiological importance.