bluuebunny/crossref_metadata_2025_split huggingface dataset:
In‐Vivo Decarboxylation of α‐Methyl DOPA and α‐Methyl Metatyrosine
Authors: Carlsson Arvid , Lindqvist Margit 
Published: December 2008

Abstractα‐Methyl DOPA (DOPA = 3,4‐dihydroxyphenylalanine) and α‐methyl metatyrosine were injected to mice (400 mg/kg intraperitoneally). The former amino acid was also injected to rabbits (200 mg/kg intravenously). At varying intervals after the injection the brains were examined for monoamines (5‐hydroxytryptamine, noradrenaline, dopamine, and α‐methyl analogues). A transient decrease in 5‐hydroxytryptamine and dopamine and a prolonged and more marked decrease in noradrenaline were observed. The α‐methyl amino acids were found to undergo decarboxylation and subsequent β‐hydroxylation in vivo. The drop in noradrenaline and dopamine levels in brain caused by the α‐methyl amino acids appears to be largely due to displacement by these decarboxylation products, which may possibly also take over the functions of the physiological amines.
Inhibition Evoked from the Region of the Caudate Nucleus in Cats
Authors: Laursen Arne Mosfeldt 
Published: December 2008

AbstractMosfeldt Laursen, A. Inhibition evoked from the region of the caudate nucleus in cats. Acta physiol. scand. 1962. 54. 185–190. – Inhibition was studied in cats trained to perform an escape or avoidance jump. Immediate arrest of movement could be elicited with low intensity when stimulating through adjacent lead pairs of a 14 lead electrode situated in the internal capsule. The cat could be “frozen” in any phase of a hurdle passage. With lead pairs in the caudate arrest of movement could only be elicited with higher intensity of stimulation, the threshold increasing with increasing distance from the internal capsule.Similarly, muscle action potentials evoked by stretch or by cortical stimulation in anesthetized and encéphale isole cats were only inhibited when stimulating through lead pairs situated in the internal capsule. Thus, there was no evidence of an inhibitory effect of caudate origin.
The Metabolism of 1‐C14 ‐Palmitic Acid in the Rat
Authors: Olivecrona Thomas 
Published: December 2008

Abstract1‐G14‐palmitic acid bound to albumin has been injected intravenously to carbohydrate‐fed male rats and plasma, liver, adipose tissue and carcass activities studied. The halflife of the injected label was 0.61 min. It was estimated that 30 % of the plasma FFA flux was taken up by the liver; 70 %, by the body remainder. 5 min after the injection 97 % of the label recovered from the liver was in esterified form. More label entered the liver NFFA pool than the liver PLFA pool. The turnover rate of liver NFFA was higher than that of liver PLFA. The same relations held for plasma NFFA and PLFA. During the first hour about 3 % of the label was found in adipose tissue. No major differences were found between samples of perirenal, epididymal and subcutaneous adipose tissue. 80 min after the injection liver and plasma lipids had the same specific activities indicating that these pools had equilibrated. At 24 hours these pools still had higher specific activities than the carcass lipids, indicating that complete mixing had still not taken place.
Effects of Chronic Central Cooling on Alimentation and Thermoregulation
Authors: Andersson B. , Gale C. C. , Sundsten J. W. 
Published: December 2008

AbstractChronic local cooling in the forebrain of 4 un‐anesthetized goats was achieved by perfusion of cold water for 1–7 days through implanted silver thermodes. In 2 goats with thermodes located in the pre‐optic region, chronic central cooling resulted in a marked inhibition of water consumption while causing little alteration of food intake. In a third goat with a thermode in the posterior pre‐optic area and the rostral hypothalamus, central cooling inhibited water intake but also increased food intake slightly. In contrast, in a fourth goat bearing a thermode rostrally in the ventromedial hypothalamus, prolonged chilling resulted in a considerable increase in hay consumption while failing to inhibit drinking. These data provide additional evidence in support of the thermostatic theory of the regulation of food intake (Brobeck 1948) and of water intake (Andersson and Larsson 1961); further, they reveal a differential response in alimentation to cooling of separate areas of the forebrain. On central cooling, all thermode goats rapidly developed sustained hyperthermia without shivering declining over 1–3 days upon cessation of central cooling. The sustained hyperthermia may be the result of peripheral vasoconstriction combined with increased metabolism of non‐shivering origin. To explain the present results, there is no need to postulate the existence of central “cold receptors” or “hypothermia detectors” within the cooled part of the brain.
Release of 5‐Hydroxytryptamine and Histamine from Rat Mast Cells1
Authors: Moran N. C. , Uvnäs B. , Westerholm Barbro 
Published: December 2008

AbstractThe release of 5‐hydroxytryptamine (5‐HT) and histamine from rat peritoneal mast cells was studied. Major variations of amine content per cell were noted. Compound 48/80, n‐decylamine, polymyxin B, phospholipase A and distilled water released 5‐HT and histamine. The concentration‐response curve for 5‐HT to 48/80 was parallel to that of histamine. The number of histamine molecules released, considered as a ratio of the number of 48/80 molecules in the medium, ranged from 4 to over 40, whereas the corresponding ratio for 5‐HT ranged from less than 1 to approximately 2. The amine release by 48/80 was dependent upon pH and temperature and took place within 20 sec at 22° C. Certain enzyme inhibitors such as allicin (SH group inhibitor) and ninhydrin (NH2 group inhibitor) blocked the amine release. Dinitrophenol inhibited the release only in glucose‐free medium. Sodium cyanide, 10‐4M, and anoxia inhibited the release of neither amine. The results suggest that 5‐HT is released from mast cells by the same mechanism as is histamine. The data are in agreement with previous evidence from this laboratory favouring an enzymatic mechanism of release of histamine by polymer amine releasing agents.
Determination of the Hepatic Galactose Elimination Capacity after a Single Intravenous Injection in Man: The reproducibility and the influence of uneven distribution
Authors: Tygstrup Niels 
Published: December 2008

AbstractTygstrup, N. Determination of the hepatic galactose elimination capacity after a single intravenous injection in man. The reproducibility and the influence of uneven distribution. Acta physiol. scand. 1963. 58. 162–172. — The hepatic galactose elimination capacity was determined from the disappearance curve in blood after a single intravenous injection. Using conventional principles for the calculation the results in repeated experiments were reproducible within 10 per cent. Comparison of the results obtained by this method with those of an infusion method showed that the latter were consistently smaller. This difference, amounting to an average of 15 per cent, might be caused by uneven distribution of galactose between its intra‐ and extravascular volume of distribution. From theoretical considerations it was deduced that the uneven distribution might be corrected for by parallel displacement of the arterial concentration curve along the time axis. Experiments with continuous infusions at different rates indicated that on the average the curve of the mean concentrations in the body was delayed 7 min in relation to the arterial curve. When the single injection experiments were corrected for this delay, the difference between the results of single injection and infusion experiments disappeared.
The Permeability of Capillaries in Various Organs as Determined by Use of the ‘Indicator Diffusion’ Method
Authors: Crone Christian 
Published: December 2008

AbstractCrone, C. The permeability of capillaries in various organs as deter‐mined by use of the ‘Indicator Diffusion’ method. Acta physiol. scand. 1963. 58. 292—305. — The theory of a single injection technique, the ‘Indicator Diffusion’ method, for quantitative studies of capillary permeability is developed. It is shown that the permeability of a capillary area can be expressed by three parameters: the initial extraction (E) of test substances added in a single injection to the blood flowing to an organ, the blood flow (Q) and the surface area (A) of the capillaries. The equation relating these figures is: P = (=/A) × loge1/(1—E). The permeability coefficients of capillaries in kidney, liver, lung, brain and hind limb to inulin and sucrose are reported. It is found that the permeability of capillaries varies considerably from organ to organ. It is questioned whether the pore model adequately describes the functional characteristics of the capillaries in the muscles. The existence of pores should result in a pronounced deviation of the ratio between the permeability coefficients for sucrose and inulin from the ratio between the free diffusion coefficients. This was not found to be the case.
The Physiology of the Swimbladder in the Eel Anguilla Vulgaris
Authors: STEEN JOHAN B. 
Published: December 2008

AbstractSteen, Johan B. The physiology of the swimbladder of the eel, Anguilla vulgaris. III. The mechanism of gas secretion. Acta physiol. scand. 1963. 59. 221–241. — The mechanism of gas secretion has been investigated by analysis of blood samples from arteries and veins at both poles of the rete associated with the gas gland. During gas deposition, as measured by gas analyses of the bladder content, the blood is enriched in lactic acid as it circulates in the bladder epithelium. The pH of this blood is about 1 pH unit lower than that in the blood entering the rete from the gills. Part of the lactic acid diffuses from venous to arterial capillaries in the rete. A gradient in gas tension across the rete is produced partly by the existing acid gradient, and partly by the delayed response of the gas tension to the change in acid content which the blood undergoes as it passes the rete. The results strongly support the theory that gas concentration occurs by a counter current multiplication in the rete of a primary gradient induced by the addition of acid electrolytes to the venous blood. The measured values on acid content, pH and blood flow agree very well with the values which have been found adequate, through calculations on the potentialities of such systems, to produce gas pressures higher than those actually measured, and it is concluded that this secretory mechanism will explain secretion of all the atmospheric gases even in deep sea fishes.
An Improved Method for Fluorimetric Determination of Small Amounts of Adrenaline and Noradrenaline in Plasma and Tissues
Authors: Häggendal Jan 
Published: December 2008

AbstractHäggendal, J. An improved method for fluorimetric determination of small amounts of adrenaline and noradrenaline in plasma and tissues. Acta physiol. scand. 1963. 59. 242–254. — By the introduction of several modifications of the trihydroxyindole method for the determination of adrenaline and noradrenaline appreciable improvement of the sensitivity has been obtained. The blank values have been considerably reduced and stabilized by substituting dimercaptopropanol (BAL) in sodium sulfite solution for ascorbic acid. The eluate volume has been reduced and the degree of purification has been increased by a modified ion‐exchange procedure (Dowex 50 W‐X8). Deproteinization of plasma before the column procedure could be omitted. When this procedure was applied to 10 ml plasma obtained from normal persons at rest, noradrenaline spectra, with two activation peaks, were usually obtained. The average concentration of the noradrenaline was 0.3 ± 0.11 μg per litre of plasma. Normally no adrenaline was found. Noradrenaline occurred in plasma in both free and conjugated form.
Effects of Some Pharmacologically Active Amines on the Uptake of Arylalkylamines by Adrenal Medullary Granules
Authors: Jonasson J. , Rosengren E. , Waldeck B. 
Published: December 2008

AbstractThe effect of reserpine, chlorpromazine and related compounds on the uptake of catecholamines by the adrenal medullary granules from the cow has been studied in vitro. Both types of drugs were found to be competitive inhibitors of the adrenaline uptake by the granules. Thus they compete with adrenaline for the same groups in the uptake mechanism for catecholamines. Tryptamine was also found to accumulate in the granules but not by the same mechanism as used by the catecholamines and 5‐hydroxytryptamine, as Mg2+, ATP and reserpine did not have any influence on the uptake. The Km‐values for the uptake of adrenaline and 5‐hydroxytryptamine were 8 × 10‐4 and 1.1 × 10‐4, respectively.
Vascular Adjustments to Increased Transmural Pressure in Cat and Man with Special Reference to Shifts in Capillary Fluid Transfer
Authors: Mellander Stefan , ÖBerg Bengt , Odelram Hannes 
Published: December 2008

AbstractWhen a vascular bed is exposed to an increased transmural pressure, as occurs in the lower extremities in man on standing, adjustments of the vascular tone take place which tend to protect the organism against excessive transcapillary loss of circulating fluid into the extravascular space. Thus, first, by closure of a number of the precapillary sphincter vessels, the size of the capillary surface area directly available for blood flow and hence for fluid exchange is reduced, and the rate of filtration correspondingly decreased. Second, by an increase of the ratio of precapillary to postcapillary flow resistance which increases the pressure drop across the precapillary resistance vessels, the rise in capillary pressure will be less than expected from the observed increase in arterial and venous pressures. From a quantitative point of view, the reduction of the capillary surface area seems to be by far the more important protective mechanism, as it was shown that in the human foot the rate of filtration per unit transcapillary pressure difference was decreased to only 1/3 to 1/8 of normal when the regional transmural pressure was increased by shifting from the supine to the erect posture.The vascular rejponse parterns described are evidently brought into play mainly by a reinforcement of the local inherent automaticity of the vascular smooth muscle induced by the raised trans. nura1 pressure, but, in all probability, can be intensified to some extent by superimpored extrinsic vasomotor fiber influence. This active vascular adaptation to hydrostatic load seems to be of greater importance than extravaicular mechanisms for preventing edema formation in dep‐ndent regions in normal subjects during quiet standing.
Effect of Nicotine and Nicotine Analogues on Tissue and Urinary Catecholamines in the Rat
Authors: Westfall T. C. 
Published: December 2008

AbstractThe time response pattern of nicotine and the nicotine analogue 3‐pyrrolidino‐methylpyridine (W‐16) on the noradrenaline (NA) content of heart, spleen, kidney and liver was studied following intraperitoneal administration in rats. It was found that both compounds produced a transient but significant decrease. Nicotine produced an effect that was visible within 5 min with the NA content returning to control levels in 60–180 min. Although quantitatively different, W‐16 produced an effect qualitatively similar to nicotine. The effect of nicotine and several nicotine analogues on the 24‐hour urinary excretion of catecholamines was also studied in rats. Three out of four analogues investigated produced a slight increase in the excretion of adrenaline (A) and NA at high dose levels (5–10 mg/kg). At a dose of 1 mg/kg, nicotine produced a significant increase in the 24 hour urinary excretion of A but not NA.
Identification and Cellular Localization of the Catecholamines in the Retina and the Choroid of the Rabbit
Authors: HÄGGENDAL JAN , MALMFORS TORBJÖRN 
Published: December 2008

AbstractHäggendal, J. and T. Malmfors. Identification and cellular localization of the catecholamines in the retina and the choroid of the rabbit. Acta physiol. scand. 1965. 64. 58–66. – By means of fluorescence microscopical and chemical methods the catecholamines of retinas and choroids were examined in rabbits normally, after treatment with drugs interfering with catecholamine storage, and after bilateral cervical sympathectomy. Dopamine was found to be the dominating catecholamine in the retina, 0.1–0.2 μg per g. It was localized to particular neurons. The results support the view that dopamine serves as the transmittor of these neurons. Noradrenaline was found in the choroid, 0.2–0.3 μg per g. It was localized to adrenergic vascular nerves.
The Distribution of Adrenergic Nerve Fibres to the Blood Vessels in Skeletal Muscle
Authors: FUXE KJELL , SEDVALL GÖRAN 
Published: December 2008

AbstractFuxe K. and G. Sedvall. The distribution of adrenergic nerve fibres to the blood vessels in skeletal muscle. Acta physiol. scand. 1965. 64. 75–86. The distribution and morphological construction of the adrenergic innervation to the various sections of the vascular bed in skeletal muscle of the cat were studied using a specific histochemical fluorescence technique. A typical adrenergic ground plexus (Hillarp 1946, 1959) was seen directly superimposed on the smooth muscle layer of the vessels. The nerve terminals seldom penetrated into this layer. The arteries entering the muscles showed only a sparse amount of adrenergic fibres, whereas the intra‐muscular arteries, arterioles and metarterioles exhibited a fairly rich supply. The innervation was uniform, no definite accumulation of adrenergic fibres being observed in any section of the vascular bed. The capillaries did not seem to receive any adrenergic fibres. The vessels on the venous side had a very sparse innervation. Single nerve bundles could be observed in relation to some small venules (20–40 μ) but only occasionally were adrenergic fibres seen around intramuscular veins with diameters above 50 μ. Possible mechanisms for the mediation of nervous vasoconstrictor stimuli to the various vessel sections are discussed.
The Metabolism of Fatty Acids in the Rat VIII. Lauric Acid and Myristic Acid
Authors: GÖRANSSON GÖRAN 
Published: December 2008

AbstractGöransson, G. The metabolism of fatty acids in the rat. VIII. Lauric acid and myristic acid. Acta physiol. scand. 1965. 64. 383–386. –Either I‐C14‐lauric acid or l‐C14‐myristic acid together with 9–10‐H3‐palmitic acid were i. v. injected into fasted and refed male rats and the disappearance of label from the blood and the tissue distribution of label studied. Both lauric and myristic acid disappeared more rapidly than palmitic acid from the blood. In refed rats lauric acid was extracted even more rapidly than myristic acid. Lauric acid was oxidized at a higher rate than myristic acid and myristic acid was more rapidly oxidized than palmitic acid. More lauric acid label and myristic acid label was found in the liver“Neutral lipid plus FFA” than in the liver phospholipids. This skewed distribution was most marked for lauric acid in the fasted rats. The uneven distribution is discussed in relation to the fatty acid composition of the liver lipids, to certain feeding experiments and to the interconversion with other fatty acids.
Vagal Relaxation of the Stomach Experimental Re‐investigation of the Concept of the Transmission Mechanism
Authors: MARTINSON JAN 
Published: December 2008

AbstractMartinson, J. Vagal relaxation of the stomach. Experimental re‐investigation of the concept of the transmission mechanism. Acta physiol. scand. 1965. 64. 453–462. – The vagus nerves contain efferent fibres capable of relaxing the corpus and fundus of the stomach. In experiments on cats this atropine‐resistant effect has been shown to differ in several respects from relaxation elicited by sympathetic stimulation or infusion of catecholamines. The vagal responses are more potent, their latency is shorter, and maximum response is attained at definitely lower frequencies. The responses to sympathetic stimulation wears off much more rapidly after the end of stimulation than does vagally induced gastric relaxation. Finally, the sympathetic or catecholamine gastric responses are more or less completely blocked by guanethidine or nethalide, which have hardly any effect on the vagal relaxation of the stomach. Hexamethonium inhibits vagal relaxation, and seems to be potentiated by atropine. It is concluded that the relaxation of the stomach on excitation of“high‐threshold” efferent vagal nerve fibres is mediated via preganglionic vagal fibres, which do not exert their effect by any adrenergic mechanism. It is still not possible to say what peripheral mechanism is actually responsible for this long‐lasting gastric relaxation.
Behavioural and Autonomic Patterns Evoked by Stimulation of the Lateral Hypothalamic Area in the Cat
Authors: Folkow Björn , Rubinstein Eduardo H. 
Published: December 2008

AbstractFolkow. B. and E. H. Rubinstein. Behavioural and autonomic patterns evoked by stimulation of the lateral hypothalamic area in the cat. Acta physiol. scand. 1965. 65. 292–299. ‐ Topical electrical stimulation of the so‐called ‘feeding centre’ and adjacent parts of the lateral hypothalamus of the cat was performed in awake animals. In some of the animals a clearly stimulus‐bound food consumption took place, and stimulation of the same structure produced in the anesthetized animals a fairly specific autonomic adjustment, involving activation of vagal fibres to the gastrointestinal tract and a sympathetically mediated cardiovascular adjustment, favoring gastrointestinal blood flow. The more frequently occurring behavioral response to stimulation of the lateral hypothalamic area involved a searching or“appetitive” exploratory response without any actual food intake during the stimulation. When stimulation in the same electrode positions was performed in the anesthetized animals no consistent or clear‐cut autonomic adjustments could be observed. The possible interrelationship between the“feeding response” and the“exploratory response” is briefly discussed. These somatomotor and visceromotor response patterns differed markedly from those obtained by stimulation of more ventrally placed but closely adjacent parts of the lateral hypothalamus. The effects induced from these electrode positions, the“alarm response”, involved a well defined attack or flight reaction, coupled with a sympathetically mediated gastro‐intestinal inhibition and a characteristic cardiovascular adjustment. favouring muscle blood flow at the expense of gastro‐intestinal blood flow.
Ascending Monoamine Neurons to the Telencephalon and Diencephalon
Authors: Andén N.‐E. , Dahlström A. , Fuxe K. , Larsson K. , Olson L. , Ungerstedt U. 
Published: December 2008

AbstractBy means of sensitive and specific methods for histochemical and biochemical determination of dopamine (DA), noradrenaline (NA) and 5‐hydroxytryptamine (5‐HT) we have succeeded in demonstrating and mapping out a number of ascending monoamine neuron systems from the lower brain stem by studying the anterograde and retrograde changes that occur in these neurons after various types of brain lesions. In this way it has been possible to discover: 1) a large, uncrossed nigro‐neostriatal DA neuron system; 2) a DA neuron system, arising from cell‐bodies in the mesen‐cephalon, ascending uncrossed in the medial forebrain bundle close to the nigro‐neostriatal DA fibres, and innervating e.g. the tuberculum olfactorium and nuc. accumbens; 3) ascending NA neuron systems with cell‐bodies situated mainly in the medulla oblongata and pons (locus coeruleus, formatio reticularis), and axons running uncrossed mainly in the medial forebrain bundle, innervating e.g. the limbic forebrain structures, the neocortex and the hypothalamus; 4) ascending 5‐HT' neurons with cell‐bodies situated mainly in the raphe nuclei of the mesencephalon (nuc. raphe dorsalis, nuc. raphe medianus), and axons running uncrossed mainly in the medial forebrain bundle, innervating e.g. the limbic forebrain structures and the hypothalamus. The effects observed on the amine levels of the neurons represent intraneuronal and not transsynaptic changes.