摘要:

AbstractAnderson, A., K. Asplundand R. Larkins,Insulin production by pancreuric islets of obese‐hyperglycemic mice cultured for one week in different glucose concentrations. Acta physiol. scand. 1978.104. 377–385.Culture of pancreatic islets isolated from obese‐hyperglycemic mice (gene symbol oh) for one week in media containing widely different concentrations of glucose (3.3, 5.6 or 16.7 mM) was found to markedly influence the functional behaviour of the islet B‐cells. Thus, the insulin content of islets cultured at 3.3 or 16.7 mM glucose (subphysiological or supraphysiological glucoce concentrations respectively) was markedly reduced. Islets cultured in 5.6 or 16.7 mM glucose displayed a normal insulin secretory response when stimulated with glucose, whereas islets cultured in a subnormal glucose concentration (3.3 mM) showed a reduced insulin response to glucose stimulation in batch type incubations and also lacked a second phase of insulin secretion in islet perifusion experiments. The rate of insulin biosynthesis of non‐cultured ob/ob islets was higher than that of islets from Lheir lean siblings but cuiture for one week in 3.3 mM glucose induced a pronounced impairment of the insulin biosynthesis in islets of obese as well as lean mice. The present data indicate that the hyperfunction of the islets of the ob/ob mouse at least in part is a reversible phenomenon, suggesting that inherent properties of islet B‐cells do not act as “primary” factors in the development of the obese‐hyper

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06292.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractUvnås‐Wallensten, K.Effect of intraantral pH on basal gastrin release into the circulation and antral lumen in anesthetized cats. Acta physiol. scand. 1978.104. 386–393.In acute experiments on cats antral pouches were perfused with solutions of different pH (1–13). After antrum passage the gastrin levels in the perfusates were measured with radioimmunoassay and the amounts of gastrin released into the antral lumen per minute calculated. The venous gastrin levels were determined concomitantly. Small amounts of gastrin (1 000–1 500 pg/min) were released into the antrum during perfusion with 0.1 M HCI. Subsequent perfusion with 0.15 M NaCl (pH 6.8) did not significantly increase the release of gastrin. On the other hand, 0.1 M phosphate buffer (pH 7.4) caused a dramatic augmentation of the gastrin output into the antral lumen (˜17fold). A concomitant increase of peripheral gastrin levels was observed. Also other alkaline solutions such as 0.15 M NaHCO, (pH 8), 0.15 M Tris buffer (pH 8) or 0.01 and 0.1 M NaOH (pH 12 and 13) promoted the release of gastrin. It is discussed whether the gastrin release at alkaline pH is induced by the alkaline pH itself or by anions such as HPO‐4HCO‐3and OH‐. The apparent effect of pH could then be due to the formation of these io

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06293.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractAnderson, K.‐E., C. G. A. Person, P. Alm, S. Kullanderand U. Ulmsten,Effects of acetylcholine, noradrenaline, and prostaglandins on the isolated, perfused human fetal urethra. Acta physiol scand. 1978.104. 394–401.Preparations of the isolated bladder‐urethral junction obtained from human fetuses at midgestation were suspended in Krebs solution (37°C), and the urethral lumen was perfused at a low rate (2 ml/h). Resistance to flow and changes in longitudinal tension were recorded. In additional experiments, isometric tension changes were recorded in isolated detrusor strips. The occurrence of adrenergic nerve terminals was investigated by the fluorescence technique of Falck and Hillarp. Acetylcholine (0.1‐1.0 μg/ml) produced a concentration‐related increase in longitudinal tension and in resistance to flow; the effects were unaffected by phenoxybenzamine (0.1μg/ml), but completely inhibited by atropine (0.1μg/ml). The effect on tension was more marked than that on resistance to flow. Noradrenaline (0.005‐1.0μg/ml) also produced a concentration related increase in longitudinal tension and in resistance to flow; the effects were abolished by phenoxybenzamine (0.1μg/ml). The amine had a more pronounced effect on resistance to flow than on longitudinal tension. ProstaglandinF2α(0.1‐0.5μg/ml) increased longitudinal tension and resistance to flow; the effects were not antagonized by atropine (0.1 pg/ml) or by phenoxybenzamine (0.1μg/ml). In preparations contracted by noradrenaline or acetylcholine, prostaglandinsEland E, (0.02‐0.2μg/ml) decreased resistance to flow and longitudinal tension. Acetylcholine (0.02‐0.2μg/ml) and prostaglandin F2α(0.0‐0.5μg/ml) contracted, noradrenaline (0.05‐0.5μg/ml) relaxed, and prostaglandin Eland E2(0.1–5.0μg/ml) had no consistent effects on the detrusor strips. Histochemically, no adrenergic nerve terminals could be demonstrated in

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06294.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractHarri, M. N. E.Metabolic and cardiovascular responses to prolonged noradrenaline load and their antagonism by beta blockade in the rat. Acta physiol. scand. 1978.104. 402–414.Rats were given daily injections of noradrenaline (0.5 mg/kg), alprenolol (20 mg/kg), or both together for 17 to 39 days. Noradrenaline injections increased the size of the heart, interscapular brown adipose tissue (ISBAT) and, when the injections were given at a thermoneutral environment, the metabolic activity of the ISBAT. Alprenolol injections tended to reduce the size of the heart and ISBAT and, at a thermoneutral environment, metabolic activity of the skeletal muscle. Furthermore, noradrenaline treatment improved tolerance against body cooling in water at 25°C and enhanced calorigenic response to injected noradrenaline. The metabolic alterations in the rats injected with both drugs together resembled more those of the animals injected with alprenolol only than those of the noradrenaline treated rats. It can be thus concluded that alprenolol, when given together with noradrenaline, antagonized noradrenaline‐induced metabolic alterations in the organism. However, the increased pressor response to infused noradrenaline, which was evident in the alprenolol treated animals, was not seen in the animals treated with both drugs. By contrast, these animals, like also the noradrenaline‐treated animals, showed decreased pressor response to noradrenaline. This finding suggests that prolonged beta blockade does not abolish the decreased sensitivity of alpha‐adrenoreceptors following prolonged noradrenaline load. On the other hand, the hypotonic response to a beta adrenergic drug, isoprenaline, was reduced by prolonged beta blockade despite simultaneous noradrenaline in

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06295.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractOlgart, L. and B. Gazelius,Inhibition of compound 48/80‐induced intradental sensory nerve activity by disodium cromoglycate and serotonin antagonists. Acta physiol. scand. 1978.104. 415–421.Local application of compound 48/80 induced long lasting nerve activity in intradental sensory nerves in the teeth of cats and dogs. This effect was inhibited by pretreatment with disodium cromoglycate (DSCG) given locally (2 × 10‐2M) or i.a. (20 mg/min). DSCG did not have any effect on the nerve excitabilityper se, as judged from the responses to hypertonic NaCl and air blasts applied to exposed dentin before and after administration of DSCG. Local treatment with lysergic acid diethylamide (0.1‐1 mg/ml) and methysergide (0.05‐0.5 mg/ml) selectively reduced or inhibited the compound 48/80 induced nerve activity. Systemic administration of methysergide (12.5μglkg) prevented the excitatory effects of compound 48/80 but was without effect when administrated during a state of established activity. The present findings support the hypothesis that compound 48/80 has an indirect effect on intradental sensory nerves and indicate that vascular reactions take part in intradental sensory nerve

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06296.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractHove, K.Effects of hyperinsulinemia on lactose secretion and glucose uptake by the goat mammary gland. Acta physiol. scand. 1978.104. 422–430.Lactose secretion by goat mammary glands was studied after intra‐arterial infusions of insulin and/or glucose causing rises in plasma insulin concentrations in mammary venous blood of about 3–5 mg/ml. Such levels are sufficient to strongly stimulate insulin sensitive processes when present in the systemic circulation. Two goats with mammary glands in situ and two with one of the glands autotransplanted to the neck were used for the experiments. Increasing the insulin concentration in blood to the mammary gland induced a decrease in lactose yields during a 3 h infusion (p<0.02). Simultaneously arterial plasma glucose decreased by 15–20 mg/100 ml to about 50 mg/100 ml. When the systemic hypoglycemic effect of the insulin infusion was offset by a simultaneous intra‐venous infusion of glucose, no significant change in lactose secretion was observed during 8 hours of hyperinsulinemia. No change in mammary glucose uptake as measured by mammary blood flow x mammary arterio‐venous glucose differences could be detected. (Average glucose uptake for 2 h before infusion: 30.9 mg/min; during 8 h of infusion: 31.2 mg/min.) It may be concluded that increased levels of insulin in the blood perfusing the mammary gland did not affect mammary glucose uptake or lactose synthesis as long as blood glucose was maintained at normal levels. The results therefore indicate that the glucose turnover in mammary glands, which in high yielding dairy ruminants represents the main organ of glucose utilization in the body, is in fact independant of changes in plasma insulin con

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06297.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

Abstractørstavik, T. B.The distribution and secretion of kallikrein in some exocrine organs of the rat. Acta physiol. scand. 1978.104. 431–442.Extractable kallikrein was quantitated in the submandibular, sublingual, and parotid glands and in the pancreas. No kallikrein was detected in the exorbital lacrimal glands and tears. The highest kallikrein concentrations (EU/ml) were in all major salivary gland secretions seen afterα‐adrenergic stimulation, less afterβ‐adrenergic and least after parasympathetic stimulation. When taking into account the large variations in salivary flow rate,α‐adrenergic stimulation was in the parotid and particularly in the submandibular gland found to result in the highest kallikrein secretory activity measured by the kallikrein secretory rate (EU/ min). This shows that the kallikrein‐rich granular tubular cells are selectively activated throughα‐adrenergic sympathetic receptors. The differences observed in the parotid saliva were small and not always statistically significant. However, when cervical nerve stimulation was superimposed upon parasympathetic stimulation, kallikrein secretory rate as well as kallikrein concentration increased. The large individual variations in salivary gland kallikrein content and secretion and the rather small differences observed in kallikrein secretory rate after nervous stimulation of the parotid and sublingual glands, may indicate that the kalli‐krein‐containing striated ducts are also influenced by factors other than the secretory nerves. The kallikrein concentration and secretory rate in urine was studied. A strong positive correlation between kallikrein secretory rate and fluid volume was found in uri

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06298.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractOlsen, U. B.The effects of ureteral occlusion and venal cenous constriction on kidney kallikrein‐kinin and prostaglandin systems in dogs. Acta physiol. scand. 1978.104. 443–452.The intrarenal pressure was raised to 40–50 mmHg by ureteral occlusion or by renal venous constriction in anesthetized dogs loaded with 10% mannitol in saline and with a urine flow of approximately I ml/min/ kidney. Both manoeuvres produced vasodilation and decreased urine creatinine excretion (GFR). Ureteral occlusion was associated with a marked antinatriuresis, which contrasted the variable decrements in sodium excretion during renal venous constriction. Ureteral occlusion did not affect urine excretion of kallikrein or kinins, whilst renal venous constriction decreased urinary kallikrein excretion, yet markedly increased urinary kinin excretion. Ureteral occlusion and renal venous constriction comparably increased urine prostaglandin (E‐like) excretion by a presumably pressure dependent mechanism. Inhibition of prostaglandin synthesis by indomethacin abolished the vasodilation during renal venous constriction and this was accompanied by marked reductions of urinary creatinine (GFR) and kallikrein excretions. whilst the kinin excretion was enhanced as observed before the administration of indom

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06299.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractRehncrona, S., B. K. Siesjöand E. Westerberg,Adenosine and cyclic AMP in cerebral cortex of rats in hypoxia, status epilepticus and hypercapnia. Acta physiol. scand. 1978.104. 453–463.The influence of hypercapnia, hypoxia and status epilepticus on cerebral cortex concentrations of adenosine, adenine nucleotides and cyclic AMP was studied on lightly anaesthetized (70% N2O) and artificially ventilated rats. Neither hypercapnia (arterial Pco2about 80 and about 300 mmHg) nor hypoxia (minimal values of 19 mmHg) altered tissue concentrations of AMP, cyclic AMP or adenosine. Bicuculline‐induced status epilepticus was accompanied by increased concentrations of cyclic AMP but adenosine concentration did not change. Experiments with ischemia, and those in which tissue hypoxia was exaggerated by unilateral carotid artery ligation, showed that tissue adenosine concentrations were elevated only when AMP concentrations rose. It is concluded that the marked increase in cerebral blood flow which occurs in hypoxia and status epilepticus is unrelated to changes in tissue adenosine concentration and that the increase in cyclic AMP during neuronal hyperactivity is triggered by other mechanisms than adenosine accumula

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06300.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY

摘要:

AbstractUvnas‐Wallensten, K.Release of substance P‐like immunoreactivity into the antral lumen of cats. Acta physiol. scand. 1978.104. 464468.SPLI can be detected in antral perfusates of cats. Experiments were performed in anesthetized cats provided with antral pouches. The pouches were perfused with 0.1 M HCI and 0.15 M NaCl. The concentration of SPLI in the perfusates was determined by radioimmunoassay. Basal output varied between 0–60 pp/min. Electrical vagal stimulation (2–10 Hz) caused release responses varying between 100–800 pg. Ach given i.v. or intraantrally also released SPLI into the antral lumen as well as adrenaline

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1978.tb06301.x

出版商:Blackwell Publishing Ltd    

年代:1978

数据来源: WILEY