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Query: UMLS:C0011570 (depression)
 172,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The objective of this study was to investigate the mechanism by which ethanol inhibits intestinal absorption of sugars. In vitro experiments on hamster jejunum have shown that the presence of ethanol in the mucosal solution caused an inhibition of the net transport of water and glucose. There was also a decrease in the intracellular water content and an increase in the intracellular sodium and potassium concentration of the gut tissue. In contrast, the intracellular glucose concentration decreased in the presence of ethanol. These ethanol-induced changes were directly related to the ethanol concentration of the mucosal solution. In the presence of 450 mM (2%) ethanol in the mucosal solution, there was also a significant inhibition of transmural potential difference, estimated glucose metabolism, and both unidirectional fluxes of sodium. The net flux of sodium to the serosal side however did not decrease significantly. These effects of ethanol cannot be fully explained by its osmotic action, and it is suggested that the ethanol-induced reduction in glucose transport could be mainly the result of an interference with the carrier-mediated coupled entrance of glucose and sodium across the brush border. A depression of cellular metabolism could also have played a role in this process.
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PMID:Effect of ethanol on sodium-dependent glucose transport in the small intestine of the hamster. 113 33

The influence of modified Type 11 electroconvulsive therapy (ECT) on plasma potasium was studied in 60 patients anaesthetized with a barbiturate and suxamethonium and the finding compared with a "control" group of patients having the same anaesthesia but not ECT. In the ECT series, plasma potassium concentration increased to a maximun 1 min after suxamethonium fasciculations and this increase occurred earlier and was more marked than that observed in the control group. It was also slightly shorter in duration, as was the comparable period of respiratory depression. These findings can be accounted for by the synchronous contraction of muscles containing blood with an increased potassium concentration following suxamethonium.
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PMID:The effect of modified electroconvulsive therapy on plasama potassium concentration. 113 48

(1) Height, weight, total body potassium, exchangeable sodium, bromide space, total body water and concentrations of sodium, potassium and chloride in plasma were measured in control subjects and individuals suffering from alcoholism, with techniques which included body counting and a multiple isotope method using 24Na, 82Br and 3H2O. (2) No differences were found between control and alcoholic subjects so there was no evidence that chronic alcoholism altered body composition. In particular there was no eficence of cellular damage or loss which would have been reflected in changes in KT or KIN. (3) The data were combined and were analysed to give information on the relationships of the variates. (4) On-going work by the author on tryptophan metabolism in primary alcoholics is compared to Shaw's findings on the kinetic behaviour of tryptophan in affective disorder. The possible prophylactic value of L-tryptophan (Optimax) in preventing both recurrent depression and recurrent alcohol abuse is outlined. (5) Data on body composition in normal subjects not hitherto available in the literature is provided.
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PMID:Body composition in control, alcoholic and depressive individuals using a multiple isotope technique and whole body counting of potassium. 118 Jan 50

In 10 out of the 13 healthy subjects a single oral dose of 1.25 mg of digoxin induced S-T-J depression and T wave flattening in the exercise ECG. Treatment with potassium-sparing diuretic, amiloride, at a dose of 5 mg twice daily for one week reversed the digoxin-induced S-T-J depression but had no effect on the T wave changes.
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PMID:Effect of amiloride on digitalis-induced electrocardiographic changes. 118 77

Interruption of coronary flow during cardiac surgical procedures provides a bloodless flaccid heart and allows precise and rapid correction of complex cardiac defects. However, myocardial damage occurs in direct proportion to the duration of the ischemia. As the induction of cardioplegia simulataneous with the initiation of cardiac ischemia helps to preserve cardiac energy reserves and thus myocardial integrity, the identification of a consistently reliable cardioplegic technique is desirable. Isolated perfused working rat hearts were made ischemic for one hour by aortic cross-clamping and were compared with hearts rendered cardioplegic at the onset of ischemia by the intracoronary administration of 5 ml of a hypothermic solution: 1) Krebs-Henseleit buffer, 2) Ringer's lactate, 3) tetrodotoxin, 4) potassium chloride, or 5) potassium citrate. Cardiac output, heart rate, aortic pressure and coronary flow were determined pre and post-ischemia. When compared to time-matched controls and hearts arrested with potassium or tetrodotoxin, the ischemia and ischemia-Ringer's lactate groups showed significant post cross-clamp depression of all measured parameters. Intracoronary Ringer's lactate, although often used as an adjunct to ischemic arrest, was not of significant value. In contrast, hearts arrested with tetrodotoxin, potassium chloride or potassium citrate showed no significant post-ischemic functional or histologic deficit. Perfusion with hypothermic Krebs-Henseleit buffer protected the myocardium better than did Ringer's lactate but less well than the tetrodotoxin or isotonic high potassium solutions. The induction of hypothermic metabolic arrest of the heart by briefly perfusing the coronary arteries via the aortic root with isotonic buffered solutions results in markedly improved myocardial tolerance to one hour of ischemia and avoids the problems of low cardiac output and ventricular irritability previously reported with hypertonic potassium citrate arrest.
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PMID:Amelioration of the effects of ischemic cardiac arrest by the intracoronary administration of cardioplegic solutions. 118 57

Previous studies from this laboratory indicated that inorganic and organic anions inhibit the unidirectional influx and net transport of the folate analog methotrexate in mammalian cells. Studies were undertaken to establish whether anions retained in uremia might inhibit the membrane transport of folates. Methotrexate was utilized as a model folate compound and its transport was determined in the Ehrlich ascites tumor cell. Influx of methotrexate was inhibited when cells were suspended into sera or ultrafiltrates of sera (pH adjusted to 7.4 by regulation of PCO2) from uremic patients, an effect that was decreased after the patient underwent hemodialysis or peritoneal dialysis. The inhibitory effect of uremic sera correlated well with the level of retained anions as estimated from the "anion gap," but could not be related to changes in osmolality, blood urea nitrogen (BUN), sodium, potassium, calcium, or magnesium. While inhibiting the influx of methotrexate, inorganic anions did not displace methotrexate from albumin binding sites. Anionic inhibition of the membrane transport of 5-methyl [14C] tetrahydrofolate was also demonstrated and this was shown to be accompanied by a depression in the rate of incorporation of the labeled 14C moiety into nucleic acids and protein. The data suggested that transport of folates is impaired in uremia and raises the possibility that whatever the measured blood folate level in the uremic individual with retained anions, the rate of uptake of folates into folate-dependent tissues which this blood folate level will sustain may be reduced.
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PMID:Inhibition of the membrane transport of folates by anions retained in uremia. 118 41

Ricinoleic acid and several structurally related compounds were tested for their effects on the smooth muscle contractions of the coaxially stimulated guinea-pig ileum, the spontaneously contracting rabbit jejunum, 90 mM potassium depolarized guinea-pig taenia coli and rat colon. In concentrations of 1.25 X 10(-5) to 4 X 10(-4) M, ricinoleate produced a dose-dependent depression of the stimulated guinea-pig ileum. This action was not produced by matching concentrations of oleate, elaidate, linoleate, 12-hydroxystearic acid, 10(9)-hydroxystearate, the methyl ester of ricinoleic acid or the trans isomer, recinelaidate. The alcohol derivative, ricinoleyl alcohol, was active and, although the depression produced by it took longer to maximize, the dose-response curves for ricinoleate and ricinoleyl alcohol on this tissue were almost superimposable. Ricinoleate showed the same qualitative and quantitative effects on the spontaneously contracting rabbit jejunum, but several differences were noted on the depolarized preparations. Ricinoleate-induced depression of depolarized smooth muscle was much slower in onset and required about 10 times higher concentrations to achieve equivalent responses. The results show that ricinoleic acid, the active ingredient in castor oil, is not a stimulant or irritant to isolated intestinal smooth muscle.
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PMID:Actions of ricinoleic acid and structurally related fatty acids of the gastrointestinal tract. I. Effects on smooth muscle contractility in vitro. 118 4

163 patients (95 hypokalemic, 48 hyperkalemic, 20 healthy) were examined. Electrocardiographic patterns of hypokalemia were evident in 46 p.c. of all patients with serum potassium less than 3,5 mval/l. Patients without cardiac disease showed signs of hypokalemia in the ECG in 68 p.c., those cases with extremly low serum potassium (less than 2,5 mval/l) in 81 p.c. In patients without cardiac disease a good correlation could be observed between ST depression and T wave inversion on one side and serum potassium level below 3,5 mval/l on the other side. The T/U ratio was found to be below unity in only 9 p.c. in mild hypokalemia, but in 82 p.c. in severe hypokalemia. ECG pattern of hyperkalemia could be found in 29 p.c. of all patients with serum potassium levels greater than 5,1 mval/l. These signs were evident in patients without cardiac disease in 29 p.c. in mild hyperkalemia, but in 75 p.c. in severe hyperkalemia. Patients suffering from cardiac disease, however showed the correspondive ECG changes of hyperkalemia only in 5 p.c. There is a good correlation between the P, and T-wave-amplitude and the serum potassium level greater than 5,1 mval/l. According to our findings it can be stated, that the ECG changes in patients with cardiac disease tend to hide the correspondive changes of potassium disorder.
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PMID:[Electrocardiographic changes in electrolyte imbalance. Part 1: Alterations in serum potassium (author's transl)]. 118 76

Myocardial contractility was examined in whole, perfused hearts and in right ventricle papillary muscles of chronic K-depleted cats. Mitochondrial and sarcoplasmic reticulum (SR) calcium binding and concentration were estimated in the perfused hearts after exposure to 45Ca. In vitro SR Ca uptake was measured by the Millipore technique. Myocardial contractility was depressed in chronic potassium depletion and the degree of depression was related to the reduced SR Ca binding. These experiments suggest altered subcellular Ca metabolism as being a mechanism of depressed myocardial contractility in chronic K depletion.
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PMID:Myocardial function and subcellular calcium metabolism in chronic potassium deficiency. 118 54

1. The 28Mg-measured net flux of magnesium from lumen-side to haemolymph-side of the isolated and short-circuited midgut was 1.97 +/- 0.28 mu-equiv cm(-2) /(-1) in 8 mM-Mg2+. 2. The magnesium-influx shows a delay before the tracer steady-state is attained, indicating the existence of a magnesium-transport pool equivalent to 6.7 mu-equiv/g wet weight of midgut tissue. 3. Magnesium depresses the short-circuit current produced the midgut but not the potassium transport, the depression being equal to the rate of magnesium transport. 4. Magnesium transport yields a linear Lineweaver-Burk plot with an apparent Km of 34 mM-Mg2+ and an apparent Vmax of 14.9 mu-equiv cm(-1) /(-1). 5. Magnesium is actively transported across the midgut and contributes to the regulation of the haemolymph magnesium concentration in vivo.
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PMID:Active transport of magnesium across the isolated midgut of Hyalophora cecropia. 120 24


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