摘要:

AbstractGöransson, G.The metabolism of fatty acids in the rat. VI. Arachidonic acid.Acta physiol. scand. 1965.64. 1–5. ‐H3‐labeled arachidonic acid and C14‐labeled palmitic acid were simultaneously injected into male rats. Arachidonic acid was preferentially incorporated into liver phospholipids as might be expected from the preponderance of this fatty acid in liver phospholipids as compared to glycerides. Initially, the labeled arachidonic acid and the labeled palmitic acid were oxidized at similar rates but at later times more arachidonic acid than palmitic acid was recovered from the whole animal. This may be explained by the preferential incorporation of arachidonic acid into phospholipid in combination with the low turnover rate of the phospholipids, especially those containing essential fatty acids. The pattern of label in the blood glycerides closely resembled that in the corresponding liver

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04148.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractHydén, H. and Lange, P. W.The steady state and endogenous respiration in neuron and glia.Acta physiol. scand. 1965.64. 6–14. –The oxygen consumption of individual, surviving nerve cells and glial cells was studied for two hours periods. An extrapolation procedure was worked out which permitted the determination of the oxygen consumption rate in the steady statein vivoand the substrate amount for endogenous respiration. The oxygen consumption rate of the neurons exceeded that of the glia by at least ten times in the steady state. The values obtained were used for calculation of the amount of glucose per nerve cell which was found to be 5 per cent of the dry weight of the cell corresponding to a 70 mM glucose solution. The amount of glucose in glia is 5 to 10 times lower than that of nerve cells. Addition of glucose or β‐hydroxybutyrate to nerve cells having respired without exogenous substrate for two hours highly increased the respiration rate. In neurons with increased RNA synthesis and respiratory enzyme activities, the respiration rate and substrate level w

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04149.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractÅberg A. K. G. and J. Axelsson.Some mechanical aspects of an intestinal smooth muscle. Acta physiol. scand. 1965.64. 15–27. – Atonic pieces of taenia coli muscle were obtained with the aid of adrenaline which abolishes spontaneous spike discharge. As reference length the in vitro length at 37° C, relaxed with adrenaline, was used. Lo(isometric) is arbitrarily defined as the greatest length of an inactive muscle when the force applied to straigthen it does not exceed 50 dynes. At this length the muscles were found to develop maximum tension. Lo(isotonic) is the preloaded length of a relaxed muscle. These conditions gave results which were repeatable with reasonable statistical accuracy, other conditions gave less reproducible results. Force‐velocity curves obeying Hill's equation (P+a) (v + b) = (Po+ a) b were obtained. Maximum velocity of shortening of an unloaded muscle was extrapolated to 30 per cent of Lo/sec. Velocity of shortening appeared related to the ratio Po: P. Rate of tension development was related to muscle length and resting tension, with a maximum at 130 to 180 per cent of Lo. The highest rate measured was 2,800 dynes/sec. Maximum physical work was performed with constant load of about 30 per cent of Po. Maximum shortening of the muscles under 100 dynes tension varied from 60–80%. The results are discussed in relation to other types

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04150.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractAxelsson, J., S. G. R. Högberg and A. R. Timms.The effect of removing and readmitting glucose on the electrical and mechanical activity and glucose and glycogen content of intestinal smooth muscle from the taenia coli of the guinea‐pig. Acta physiol. scand. 1965.64. 28–42. The effects of changing the glucose concentration in the bathing solution on frequency of spike discharge, membrane potential, and on the mechanical responses is described quantitatively and related to tissue content of glucose and glycogen. Removing glucose increases and readmitting inhibits spike discharge. The membrane potential depends on carbohydrate metabolism for its maintenance. Its dependence is, however, quantitatively or qualitatively different from that of the contractile mechanism. Spike discharge of high frequency persisted for hours after the mechanical response was abolished. In glucose‐free solution the mechanical response fell in parallel with tissue content of glycogen. In normal solution there was no correlation between tension and glycogen c

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04151.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractFex, J.,Auditory activity in uncrossed centrifugal cochlear fibres in cat. A study of a feedback system, II.Acta physiol. scand. 1965.64. 43–57. – In decerebrate cats all of the cochlear efferents except the uncrossed olivo‐cochlear fibres were cut, the vestibulo‐cochlear anastomosis was exposed through the vestibule and single unit activity was recorded in, and close to, the anastomosis with micropipette electrodes. Although the auditory function was destroyed in the dissected cochlea, resting activity was found in primary auditory afferents, suggesting that synaptic mechanisms could still be intact in such a preparation. – Uncrossed olivo‐cochlear fibres were activated by electrical stimulation of the ipsilateral cochlear nerve and by acoustic stimulation of the contralateral ear. When activated by sound, the uncrossed efferents in the basal fascicle of the anastomosis generally responded to higher tone frequencies than did fibres in the apical fascicle, which suggests that afferents and uncrossed efferents from homotopic cochlear points in opposite cochleae are connected. The fibres responded characteristically with a low, regular firing rate without an initial burst and with a long latency at threshold, indicating that their input would be integrated over a considerable time. Many of the efferents showed resting activity which, with few exceptions, could be inhibited by sound depending on the choice of tone frequency. – The findings suggest that the uncrossed cochlear efferents and ipsilateral auditory afferents together form an auditory, closed feedback loop, which is directly influenced by the contralateral ear and support the hypothesis (Fex 1962) that the uncrossed and the crossed olivo‐cochlear bundles together form a complex, auditory fee

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04152.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

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 vascu

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04153.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractDiamant, H. B. Oakley, L. Ström, C. Wells and Y. Zotterman.A comparison of neural and psychophysical responses to taste stimuli in man. Acta physiol. scand. 196564. 67–74. – Electrophysiological records of taste activity have been obtained from the chorda tympani nerve of otosclerotic patients. When possible, preoperative psychophysical responses to taste stimuli were also obtained. The summated chorda tympani discharge to 0.2 M NaCl adapts completely and the time required agrees with psychophysical reports. Psychophysical estimates of the sweetness of different sugars correspond closely with nerve response magnitudes. Gymnema extract abolishes both the sweet sensation and the nerve response to sweet tasting chemicals. The total sum of taste activity in the entire chorda tympani nerve appears to be an important determinant of the psychophysical responses. There are large individual differences in the relative size of the neural response to different taste stimuli. Responses to ethyl alcohol are descr

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04154.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

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 di

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04155.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractNissen, O. I.The magnitude of the skimming phenomenon in the interlobular arteries of the cat kidney. Acta physiol. scand. 1965.64. 87–92. – Samples simultaneously collected from the arterial system, from the deep renal veins and from the subcapsular renal veins in the cat kidney have been analysed with respect to red cell volume, plasma proteins, plasma osmolality (and plasma PAH). The ratio: subcapsular venous concentration/arterial concentration was on an average 1.10 for the red cells, 1.09 for the plasma proteins, and 0.99 for plasma osmolality. The ratio: deep venous concentration/arterial concentration was on an average 0.90 for the red cells, 0.89 for the proteins, and 1.03 for the osmolality. The difference between the protein ratios and a part of the difference between the hematocrit ratios may be attributed to the fact that a part of the fluid lost by ultrafiltration from the blood traversing the outer cortex is reabsorbed in the loops of Henle and the collecting ducts and thus will be added to the blood leaving the kidney by way of the deep veins. A smaller part of the difference between the hematocrit ratios may be explained from the alterations in the tonicity of the blood during its passage through the kid

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04156.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY

摘要:

AbstractOttoson, D.The effect of osmotic pressure changes on the isolated muscle spindle.Acta physiol. scand. 1965.64. 93 105.– The action of hypertonic and hypotonic solutions on the sensory endings of the muscle spindle has been studied in isolated preparations. It was found that changes of osmotic pressure by more than 25 per cent caused an augmentation of the activity of the resting spindle and modified its sensitivity to stretch. Increase of pressure produced a discharge the peak frequency of which increased linearly with osmotic strength. The maximum effect was usually obtained with concentrations of four to five times that of Ringer's solution. The responsiveness of the spindle to stretch decreased with increasing pressure. Decreasing the osmotic pressure produced a short‐lasting increase of the activity of the resting spindle followed by a decline and final cessation of the discharge. The responsiveness to stretch was increased during the period of repetitive firing and then decreased. Washing with Ringer's solution after immersion in hypotonic solutions regularly produced a prolonged discharge and a reduced sensitivity to stretch. It is concluded that the observed changes are mainly due to osmotic effects on the sensory endings of the spindle. The results suggest that the endings behave as simple osmotic sacs within a limited range of osmotic strengths and that the sensory membrane is equally sensitive to distention and fold

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1965.tb04157.x

出版商:Blackwell Publishing Ltd    

年代:1965

数据来源: WILEY