bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Relation Between Blood Flow in an Isolated Muscle Measured with the Xe133 Clearance and a Direct Recording Technique
Authors: Kjellmer I. , Lindbjerg I. , Přerovský I. , Tønnesen H. 
Published: December 2008

ABSTRACTTo allow a critical evaluation of the Xe133 clearance technique this method was compared with directly metered blood flow in the isolated gastrocnemius muscle of cats at different flow levels between rest and maximum exercise dilatation. Whether the Xe133 was applied by close intraarterial injection or intramuscularly the clearance curve had a multiexponential course. This was ascribed partly to local variations of the affinity of the tissues to the gas but mainly to an uneven perfusion of the muscle. When the first phase of the clearance curve was approximated by a monoexponential curve and was taken to represent blood flow a significant correlation to metered flow was found. With i.a. injections the calculated flow amounted to an average of 93 per cent of the drop counter flow while after i.m. injections it only averaged 62 per cent. The difference in results is ascribed to the different microcirculatory conditions created by the two modes of injections. The relative volume of the well‐perfused part of the tissue was estimated by noting at which level of activity the curve deviated from the first phase of rapid clearance. The well‐perfused fraction increased at higher blood flows. It is concluded that the Xe133 clearance technique may give valuable information about the local circulation provided the limitations of the method are considered.
An Improved Method for the Fluorimetric Determination of 5‐Hydroxytryptamine in Tissues
Authors: Andén Nils‐Erik , Magnusson Tor 
Published: December 2008

ABSTRACTIn the method described where the fluorescence of 5‐hydroxytryptamine (5‐HT) is read in 3 N HCl, tissue blanks are produced by means of UV‐irradiation in the presence of potassium ferricyanide. This treatment destroys only the 5‐HT but no other substance fluorescing at 295/545 mμ. With this new type of blank and by reduction of the volumes of the eluate and the reagents the sensitivity of the method is improved so that 25 ng (1 ng = 10‐9 g) in an extract can be demonstrated and 50 ng determined quantitatively. The stability of 5‐HT in 0.4 N perchloric acid extract is increased by adjustment of the pH almost to neutrality and by addition of ascorbic acid and ethylenediamine tetraacetate. The recovery and reproducibility are satisfactory.
Further Studies on Monoamine Metabolism and Behaviour in Rabbits Chronically Treated with Reserpine
Authors: Häggendal Jan , Lindqvist Margit , Roos Björn‐Erik 
Published: December 2008

ABSTRACTAfter a single dose of reserpine (1 mg/kg intravenously) to rabbits the symptoms appeared when most of the monoamines still were present in brain and heart. In long‐term reserpine treated rabbits (0.2 mg/kg subcutaneously daily for more than 8 weeks) the monoamine metabolism was studied with respect to normetanephrine, homovanillic acid and 5‐hydroxyindoleacetic acid. In the chronically treated animals the deaminated metabolites appeared essentially as after a single dose of reserpine whereas normetanephrine showed a slower recovery in the chronically treated animals. Gross inspection of behaviour and sympathetic activity following DOPA injection revealed no clearcut changes in the response to DOPA in rabbits chronically treated with reserpine compared to normal animals.
The Effect of Reserpine and Tetrabenazine on the Accumulation of Noradrenaline in the Rat Sciatic Nerve after Ligation
Authors: Dahlstrom Annica 
Published: December 2008

ABSTRACTThe accumulation of noradrenaline (NA) in the rat sciatic nerve after ligation was studied at different intervals after the administration of reserpine and tetrabenazine. The histochemical fluorescence method of Hillarp and coworkers was used. It was found that the two drugs were both able to abolish the NA fluorescence above and below both single and double ligations. Pretreatment with nialamide prevented the disappearance of NA occurring after reserpine. The reappearance of NA above a 1 hr ligation of the sciatic nerve occurred 15–18 hrs after an intraperitoneal injection of reserpine. The first signs of the reappearance was observed above a high ligation about 3 hrs before it could be seen above a ligation performed about 2 cm lower. The same pattern of recovery of NA in the sciatic nerve was observed in animals treated locally with reserpine on the ganglia, from which the adrenergic nerves in the sciatic nerve take their origin. However, the fluorescence of NA in these animals usually reappeared about 3 hrs earlier than in systemically treated animals. The restituted NA could be abolished by a second dose of reserpine. In double ligated rats recovery of NA after reserpine could be observed only above the upper ligation. After tetrabenazine, however, double ligated nerves regained the NA content almost completely above both lesions within 12–15 hrs. The results give strong support to the view that the amine storage granules are manufactured in the cell body and transported down the axons to the terminals.
The Effect of Bile Obstruction on the Oxidation Rate of Ethanol in the Rat
Authors: Kiessling K.‐H. , Pilstrom L. 
Published: December 2008

ABSTRACTIn male Wistar rats the bile duct was tied up. Control rats were given a sham operation. After a week a single ethanol dose was given intraperitoneally and blood samples were analysed for ethanol. In the rats with obstructed bile flow, ethanol was oxidized at a considerably lower rate than in the controls. The possible reasons for this are discussed.
Influence of Adrenaline on the Content of Adenosine Triphosphate and Creatine Phosphate in Isolated Rat Diaphragm
Authors: Mohme‐LuWdholm Ella , Svedmyr Nils , Vamos Nandor 
Published: December 2008

ABSTRACTAdrenalinc in a concentration of 10‐6 g/ml increased the content of adenosine triphosphatc (ATP) and creatine phosphate (CrP) in isolated rat diaphragm, by an average of 100 per cent 15 min after its addition.
Skin D.C. Potentials and the Endosomatic Galvanic Skin Reaction in the Cat
Authors: Lang A. H. 
Published: December 2008

ABSTRACTD.C. potential recordings have been made on different skin areas in cats. A negative d c. potential exists on the volar, hairless skin areas of the paws. This ‘basal potential’ persists even though the limb is denervated, decreases reversihily when the arterial blood circulation is arrested for a short time in the limb, but disappears when the animal is sacrificed. A d.c. potential change is also induced by intravenously administered succinylcholine. It is not limited to the skin but seems to arise in the striated muscles. The endosomatic galvanic skin reaction, GSR, induced after a period of rest by a single electrical shock to the distal stump of the dissected sciantic nerve, includes both a fast, negative and a slow, most often positive component. The amplitude of the negative component does not change during the above‐mentioned d.c. changes. By repetitive stimuli the slow components fuse and cause a change in the basal potential. The amplitude of the fast component increases often simultaneously, but these two potential changes seem to be independent. The nature of the mechanisms maintaining and changing the basal potential and the relationships between the basal potential and the GSR are discussed.
Mechanism of Calcium and Adenosine Triphosphate Induced pH Changes in Sarcotubular Membrane Fractions from Rabbit Skeletal Muscle
Authors: Herniö Ulla‐Pia , Saris Nils‐Erik 
Published: December 2008

AbstractAddition of calcium to a suspension of sarcotuhular membrane fragments in the presence of MgCl2 and ATP caused a drop in pH followed by a rise. The pH cycle could be obtained several times by sequential additions of calcium. Addition of Triton X—100 caused similar pH changes, which were substantially slower in the absence of magnesium. During the pH drop phase an increased rate of inorganic phosphate liberation was observed, during the pH rise phase production of ammonia was demonstrated. The pH events are explained by the combined action of three enzyme activities —ATP phosphohydrolase (E.C. 3.6.1.3), ATP:AMP phosphotransferase (E.C. 2.7.4.3) and AMP aminohydrolase (E.C. 3.5.4.6). The highest specific activity of AMP aminohydrolase was found in the sarcotubular membrane and ‘light’ membrane fractions. Accumulation of calcium in conditions where binding by mitochondria was excluded, was used as a biochemical marker for sarcotubular membranes. These findings are discussed in relation to pH changes observed in muscular activity and as a mechanism of preventing excessive drops in muscular intracellular pH.
The Effect of Eight New Prostaglandins on Human Myometrium
Authors: Bygdeman M. , Hamberg M. 
Published: December 2008

AbstractHuman semen contains 13 different prostaglandins. The effect of 5 of these (PGE1, PGE2, PGE3, PGF1a and PGF2a) on the motility of human myometrium in vitro has been described earlier. The 8 new compounds are derivatives of the PGE‐compounds formed by hydroxylation at C‐19 and/or dehydration involving the hydroxyl group at C‐11. All the compounds inhibited the motility of the myometrium in a similar way as the PGE‐compounds. The total effect of the 19‐hvdroxylated compounds was 4–40 per cent and of the dehydrated compounds 3–30 per cent of that of the PGE‐compounds.
Cholinesterase Activity in Innervated and Denervated Sympathetic Ganglion Cells of the Cat
Authors: Giacobini Ezio , Palmborg Bo , Sjöqvist Folke 
Published: December 2008

AbstractTotal cholinesterase [ChE, acetylcholine (AcCh) as substrate] and acetylcholinesterase [AcChE, acetyl‐β‐methylcholine (MeCh) as substrate] were determined with the Cartesian diver in single sympathetic cell bodies isolated from the normal and preganglionically denervated 7th lumbar ganglion of the cat. Thirty normal cell bodies showed a wide variation in total ChE acitivity from 3 times 10‐‐4to 160 times 10‐‐4μl CO2/hour. Cell bodies with low activity represented the majority of the population, while cell bodies with very high activity were rare. AcChE‐activity in 10 normal cell bodies varied between 3.8 and 54.4 times 10‐‐4μl CO2/hr. After denervation there was a significant decrease in average enzyme activity as measured with both substrates. This is probably explained by the loss of presynaptic AcChE‐rich terminals which stick to the normal cell bodies. With AcCh the enzyme activity varied between 2.7 and 28.5 times10‐‐4μl CO2/hour (n = 16) and with MeCh between 2.9 and 31.1 times 10‐‐4μl CO2/hour (n = 10). Thirty‐five per cent of the denervated cells (9/26) lacked measurable activity. The ratio of AcCh/MeCh hydrolysis decreased after denervation 1.7 to 1.0. These findings support the previous concept of two functionally different cell populations in sympathetic ganglia.
The In Vitro Catabolism of Histamine by Sheep Liver Tissue
Authors: Sjaastad Ø. V. 
Published: December 2008

AbstractThein vitroinactivation of histamine by the liver of sheep has been examined with the following results: At optimal substrate concentrations liver slices inactivated 178.5±57.4(S.D.) μg histamine diphosphate/g wet weight of tissue/hr. There was no marked difference between the histamine inactivation in liver slices and homogenates.‐Aminoguanidine, a powerful inhibitor of diamine oxidase (E.C. 1.4.3.6.), strongly counteracted the histamine inactivation, indicating that oxidative deamination is the major pathway for histamine inactivatoin in sheep liver tissuein vitro.‐On an average about 1 per cent of added histamine was inactivated by conjugation.‐Inhibition experiments indicated that no significant methylation takes place.‐The average content of preformed histamine in 41 sheep was 24.7±11.1 μg histamine diphosphate/g wet weight of tissue.
Determination of Histamine in Small Biopsies and Histological Sections
Authors: Juhlin Lennart 
Published: December 2008

AbstractA method is described for rapid determination of histamine in small tissue biopsies (0.5–7.5mg) and freeze‐dry histological sections. Free hitamine base was detected in a concentration of 105ng/ml. Thed essential steps in the procedure are: After repeated freezing and thawing of the specimens they are placed in wells on agar gel plates. Electrophoresis for 10 min separates histamine in pH 4.6 buffer. orthophthaldialdehyde is added with sodium hydroxide, and the fluorescent complex formed with histamine is stabilzed with sulphuric acid and measured flurometrically. The histamine content of normal human skin varied between 1.4–5.6 μg/g. No histamine was found in the superficial part of the epkidermis. The basal cell layer and the papillae had the highest concontainedj 4.1–30.1 μg/g. Staining for histamine revealed a diffuse distribution here. The muscularis contained 0.9–2.3 μg/g located mainly in the mast cells. Various organs in monkeys were also examination. The highest histamine concentration was found in the lungs (14–87 μg/g). In the kidney histamine appears especially in the glomeruli.
Transcapillary Fluid Absorption and Other Vasular Reactions in the Human Forearm during Reduction of the Circulating Blood Volume
Authors: Mellander Stefan , ÖBerg Bengt 
Published: December 2008

AbstractThe responses of the human forearm vascular bed to a reduction of circulation blood volume, produced by pooling about 600 to 800 ml of blood in the legs, were followed by a plethysmographic technique. The pattern of vascular response was similar to that previously found in anesthetized animals after hemorrhage. It involved a reflex constriction of resistance and capacitance vessels and a net transcapillary absorption of extravascular fluid. The capillary filtration coefficient averaged 0.0061 ml/min × 100 g tissue × mm Hg, and did not change significantly during the pooling of blood, indicating no major change of precapillary sphincter tone. The absorption of extravascular fluid can be related to a fall in capillary hydrostatic pressure, which is, in turn, due to a reflex increase of the pre‐ to postcapillary resistance ratio. This process seems to aid greatly in the restoration of plasma volume. A reflex resetting of the pre‐to postcapillary resistance ratio might therefore consitute an important component in the overalll cardiovascular compensatory adjustments to reduced circulating blood volume in man.
Sympathetic Control of Consecutive Vascular Sections in Canine Subcutaneous Adipose Tissue
Authors: ÖBerg Bengt , Rosell Sune 
Published: December 2008

AbstractThe effects of electrical stimulation of sympathetic nerves to subcutaneous adipose tissue in the dog on the flow resistance, regional blood volume and the capillary filtration coefficient (CFC) were studied. The resting blood flow varied between 3.2–12 ml/min × 100 g and resting CFC between 0.02–0.035 ml/min × 100 g × mm Hg (mean=0.027). The regional blood content was approximately 5 ml/100 g. Stimulation of the regional sympathetic nerves induced a pronounced decrease in blood flow, a two to threefold increase in CFC, a net transcapillary fluid absorption and a decreased regional blood volume. Stimulation following administration of an α‐blocking agent produced a blood flow increase up to 25–30 ml/min × 100 g, a small CFC increase and a small venous dilation. These vascular respones were blocked by a β‐blocking agent (propranolol). In comparison with skeletal muscle the vascular bed of subcutaneous adipose tissue was found to be well dimensioned for transcapillary exchange at comparable total blood flows. This was shown by the relatively high CFC values, which indicated a large capillary surface area and/or a high capillary permeability.
Dissimilarities between the Central Control of Thirst and the Release of Antidiuretic Hormone (ADH)
Authors: Andersson B. , Olsson K. , Warner R. G. 
Published: December 2008

AbstractEffects of slow (7.5 μu1/min) infusions of certain hypertonic solutions into the 3rd brain ventricle were studied in 4 unanesthetized goats. The only solutions found to elicit drinking were NaCl (0.85 M) and to a minor degree) NaHCO3 (0.85 M). Other solutions tested (0.85 M solutions of Na‐acetate and NH4Cl, and 1.7 M solutions of urea and d‐glucose) were negative in this respect. During 1 hr infusions of NaCl a strong cumulative drinking response was obtained in all animals within 3 to 8 min after start of the infusion. No drinking occurred when the animals were hydrated prior to the infusion. The effects on water diuresis of short (2 to 10 min) periods of infusion of the same hypertonic solutions were studied in 3 goats after previous hydration. In 2 of the animals 4 min periods of infusion of the sodium salts and of NH4Cl caused an inhibition of water diuresis of the neurohypophysial type, paralleling the effect of an i.v. injection of approximately 4 mU of ADH. A considerably smaller effect was obtained by urea and no inhibition of water diuresis was seen due to infusions of d‐glucose. In one of the goats no inhibition of water diuresis was obtained from either NaCl or NH4Cl. In this animal the site of infusion was more posterior and ventral in the 3rd ventricle than in the responding animals.
The Effects of CO2 and Hydrogen Ions on Active Na Transport in the Isolated Frog Skin
Authors: Funder Jørgen , Ussing H. H. , Wieth J. O. 
Published: December 2008

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

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

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

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

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