Mineral Metabolism in Affective Disorders

1965 ◽  
Vol 111 (481) ◽  
pp. 1133-1142 ◽  
Author(s):  
Alec Coppen
Keyword(s):  
Sodium Chloride ◽  
Affective Disorders ◽  
Extracellular Space ◽  
Action Potentials ◽  
Mineral Metabolism ◽  
Extracellular Fluid ◽  
Sodium Concentration ◽  
Intracellular Concentration ◽  
Physiological Research ◽  
Very High

Physiological research has shown the fundamental importance of electrolytes in the functioning of the cell. According to the ionic theory, the resting and action potentials of nerve and muscle cells depend on potassium, sodium, chloride and other ions having a different concentration inside the cell to the concentration they have in the extracellular fluid. The cell membrane is freely permeable to potassium and chloride, but is much less permeable to sodium, and there is active transport of sodium which keeps the sodium concentration within the cell at about 1/10 of the concentration of sodium in the extracellular space. Because of this uneven distribution of sodium and the presence within the cell of impermeable anions (such as glutamic acid), potassium and chlorine are also unevenly divided between the cell and the extracellular fluid; potassium has a very high intracellular concentration and chlorine a low intracellular concentration compared to their concentration in the extracellular space.

Ionic Composition of Haemolymph and Nervous Function in the Cockroach, Periplaneta Americana L

1968 ◽  
Vol 49 (1) ◽  
pp. 31-38
Author(s):  
Y. PICHON ◽  
J. BOISTEL
Keyword(s):  
Action Potentials ◽  
Periplaneta Americana ◽  
Extracellular Fluid ◽  
Sodium Concentration ◽  
Resting Potential ◽  
Equilibrium Potential ◽  
Unequal Distribution ◽  
High Sodium ◽  
Giant Axons ◽  
Nerve Cords

1. Resting and action potentials have been recorded in giant axons of the cockroach when the intact nerve cord was bathed in the insect's own haemolymph. 2. Low resting potentials (43.0±4.8 mV.) and large action potentials (105.1±6.8 mV.) were obtained in these preparations as compared with those recorded in de-sheathed nerve cords. 3. Recordings of the maximum rates of rise and fall have shown that the shape of the action potential was essentially similar in de-sheathed preparations and in intact nerve cords. 4. These results have been discussed in terms of the unequal distribution of ions between the haemolymph, the extracellular fluid and the axoplasm of the giant axons. 5. The low measured resting potential agrees with a K+ concentration in the haemolymph of about 20 mM./l., a value which is only slightly lower than the measured one (Pichon, 1963). 6.The occurrence of large action potentials in these apparently depolarized axons may be related to the stabilizing action of divalent cations such as Ca2+ which are contained in the extracellular fluid in relatively large amounts. 7. The very large recorded overshoots (62.1±7.0 mV.) may be linked with a low sodium concentration in the axoplasm and a high sodium concentration in the extracellular fluid of the giant axons of intact nerve cords, thus resulting in a high sodium equilibrium potential, ENa.

scholarly journals Contraction and Action Potentials of Frog Heart Muscles Soaked in Sucrose Solution

1962 ◽  
Vol 46 (1) ◽  
pp. 35-56 ◽  
Author(s):  
William G. Van der Kloot ◽  
Nira S. Rubin
Keyword(s):  
Action Potential ◽  
Cardiac Muscle ◽  
Extracellular Space ◽  
Action Potentials ◽  
Sucrose Solution ◽  
Extracellular Fluid ◽  
Frog Heart

Isolated auricles or ventricles from the frog continue to contract, either spontaneously or when stimulated, for from 2 to 4 hours after they are placed in isotonic sucrose solution. After the muscles stop contracting in sucrose solution, contractility is partially restored when the muscles are placed in chloride Ringer's. However, contractility is usually not restored if the muscles are placed in sulfate Ringer's. Ventricles soaked in sucrose solution at 4–7°C continue to contract for 12 to 24 hours and during the first few hours in sucrose solution the contractions often are enhanced. Several types of experiment indicate that the sucrose solution does replace the Ringer's in the extracellular space. Auricles and ventricles also continue to conduct action potentials, with an overshoot, for from 30 to 360 minutes after being placed in sucrose solution. Muscles soaked in sucrose until they are inexcitable rapidly recover in chloride Ringer's but often fail to recover in sulfate Ringer's. The results are discussed in relation to theories about the generation of the action potential in cardiac muscle, and the role of the extracellular fluid in contraction.

Lithium in mania and depression

1966 ◽  
Vol 4 (26) ◽  
pp. 103-104
Keyword(s):  
United States ◽  
Fluid Balance ◽  
Affective Disorders ◽  
Mineral Metabolism ◽  
The United States ◽  
Cardiac Patients ◽  
Lithium Poisoning ◽  
Salt Substitute

In 1949 Cade1 introduced lithium into psychiatric use in Australia demonstrating its efficacy in the treatment of manic excitement. Unfortunately the drug almost immediately acquired a sinister reputation in the United States when its use as a salt substitute in cardiac patients caused a number of deaths from lithium poisoning.2 In Europe the advent of chlorpromazine and reserpine in the early 1950’s delayed the development of lithium; but in the last few years interest has revived as knowledge of fluid balance and mineral metabolism in affective disorders has increased.3

Phase resetting of spontaneously beating embryonic ventricular heart cell aggregates

1986 ◽  
Vol 251 (6) ◽  
pp. H1298-H1305 ◽  
Author(s):  
M. R. Guevara ◽  
A. Shrier ◽  
L. Glass
Keyword(s):  
Action Potentials ◽  
High Amplitude ◽  
Heart Cell ◽  
Cell Aggregates ◽  
Embryonic Chick ◽  
Phase Resetting ◽  
Stimulus Amplitude ◽  
High Stimulus ◽  
Very High ◽  
Spontaneous Rhythm

The influence of isolated 20-ms duration current pulses on the spontaneous rhythm of embryonic chick ventricular heart cell aggregates was studied. A pulse could either delay or advance the time of occurrence of the next action potential, depending on whether it fell early or late in the cycle. As the stimulus amplitude was increased, the transition from delay to advance occurred over a narrower range of coupling intervals. At low-stimulus amplitudes the transition from delay to advance occurred in a smooth continuous fashion; at medium-stimulus amplitudes the transition was discontinuous; at high-stimulus amplitudes graded action potentials were seen. It was impossible to annihilate spontaneous activity in aggregates with a single stimulus. The phase-resetting response to hyperpolarizing pulses was qualitatively the reverse of that produced by depolarizing pulses. A very high-amplitude depolarizing or hyperpolarizing pulse could produce rapid repetitive activity. Theoretical aspects of these phenomena are discussed.

scholarly journals Vascular calcification has a role in acute non-renal phosphate clearance

2020 ◽  
Author(s):  
Mandy E Turner ◽  
Austin P Lansing ◽  
Paul S Jeronimo ◽  
Lok Hang Lee ◽  
Bruno A Svajger ◽  
...  
Keyword(s):  
Vascular Calcification ◽  
Phosphate Uptake ◽  
Mineral Metabolism ◽  
Extracellular Fluid ◽  
Systemic Response ◽  
Phosphate Homeostasis ◽  
Rat Models ◽  
Oral Consumption ◽  
Circulating Levels ◽  
Systemic Disposition

AbstractRationaleNon-renal extravasation of phosphate from the circulation and transient accumulation into tissues and extracellular fluid is a regulated process of acute phosphate homeostasis that is not well understood. Following oral consumption of phosphate, circulating levels normalize long before urinary excretion has been completed. This process is especially relevant in the setting of chronic kidney disease (CKD), where phosphate exposure is prolonged due to inefficient kidney excretion. Furthermore, CKD-associated dysregulation of mineral metabolism exacerbates pathological accumulation of phosphate causing vascular calcification (VC).ObjectiveDetermine whether the systemic response to acute phosphate challenges is altered by the development and progression of VC.Methods/ResultsAcute circulating and tissue deposition of an acute phosphate challenge was assessed in two rat models of VC using radio-labelled phosphate tracer. In an adenine-induced model of CKD with VC, animals with VC had a blunted elevation of circulating 33PO4 following oral phosphate administration and the discordant deposition could be traced to the calcifying vasculature. In a non-CKD model of VC, VC was induced with 0.5ug/kg calcitriol and then withdrawn. The radio-labelled phosphate challenge was given to assess for vascular preference for phosphate uptake with and without the presence of an active calcification stimulus. The new transport to the calcifying vasculature correlates to the pre-existing burden of calcification, and can be substantially attenuated by removing the stimulus for calcification. The accrual is stimulated by a phosphate challenge, and not present in the same degree during passive disposition of circulating phosphate.ConclusionsOur data indicate that calcifying arteries alter the systemic disposition of a phosphate challenge and acutely deposit substantial phosphate. This study supports the importance of diet as it relates to acute fluctuations of circulating phosphate and the importance of bioavailability and meal-to-meal management in CKD patients as a mediator of cardiovascular risk.

Direct Microprobe Evidence of Local Concentration Gradients and Recycling of Electrolytes During Fluid Absorption in the Rectal Papillae of Calliphora

1980 ◽  
Vol 88 (1) ◽  
pp. 21-48 ◽  
Author(s):  
BRIJ L. GUPTA ◽  
BETTY J. WALL ◽  
JAMES L. OSCHMAN ◽  
T. A. HALL
Keyword(s):  
Extracellular Fluid ◽  
Sodium Concentration ◽  
Dry Mass ◽  
Local Concentration ◽  
Concentration Gradients ◽  
Sodium Potassium ◽  
Local Osmosis ◽  
Intercellular Channels ◽  
Tissue Compartments ◽  
Micro Analysis

1. The concentrations of sodium, potassium and chloride and dry mass were measured by electron-probe X-ray micro-analysis in 1 μm thick frozen-hydrated sections from Calliphora rectum in 5 different states of absorptive function. 2. In all cases the average concentrations of sodium + potassium + chloride was consistently higher in the fluid in the lateral intercellular spaces than in the cytoplasm, the average ratio being 2:1 in water-fed flies and higher in water-deprived flies. 3. The highest concentration of electrolytes was found in the extracellular channel of complex lateral membrane stacks, which is consistent with the histochemical localization of major cation pumps at these sites (Berridge & Gupta, 1968). This concentration exceeded the electrolyte concentration in other tissue compartments by some 80 m-equiv/1 H2O in water-fed flies and about 700 m-equiv/1 H2O in water-deprived flies. The potassium and sodium concentration ratio of this extracellular fluid was nearly 1:1 in water-fed flies, 3:1 in water-deprived flies with KC1 in the rectal lumen, and 0·5:1 with NaCl in the rectal lumen. 4. Results suggest that the extracellular fluid is generated in membrane infoldings along the intercellular channels, and that this fluid gains water and sodium, but loses a variable amount of potassium and chloride, as it passes to the haemolymph, thus supporting the idea of local osmosis and ion recycling.

Effectiveness of the aldosterone-sodium and -potassium feedback control system

1976 ◽  
Vol 231 (3) ◽  
pp. 945-953 ◽  
Author(s):  
DB Young ◽  
RE McCaa ◽  
UJ Pan ◽  
AC Guyton
Keyword(s):  
Feedback Control ◽  
Potassium Concentration ◽  
Extracellular Fluid ◽  
Plasma Potassium ◽  
Sodium Concentration ◽  
Feedback Mechanism ◽  
Fluid Volume ◽  
The Body ◽  
Plasma Sodium ◽  
Aldosterone Secretion

This study was conducted to determine the quantitative importance of the aldosterone feedback mechanism in controlling each one of three major factors that have often been associated with aldosterone, namely, extracellular fluid sodium concentration, extracellular fluid potassium concentration, and extracellular fluid volume. To do this, the ability of the body to control these three factors in the face of marked changes in daily sodium or potassium intake was studied under two conditions: 1) in the normal dog, and 2) in the dog in which the aldosterone feedback mechanism was prevented from functioning by removing the adrenal glands and then providing a continuous fixed level of supportive aldosterone and glucocorticoids during the low and high electrolyte intake periods. Under these conditions, removal of feedback control of aldosterone secretion decreased the effectiveness of plasma potassium control by nearly fivefold (39% vs. 8% change in plasma potassium concentration), fluid volume by sixfold (12% vs. 2% change in sodium space) and had no effect on control of plasma sodium concentration (2% change with and without feedback control of aldosterone secretion.)

Lysophosphoglycerides in ischemic myocardium effluents and potentiation of their arrhythmogenic effects

1981 ◽  
Vol 241 (5) ◽  
pp. H700-H707 ◽  
Author(s):  
D. W. Snyder ◽  
W. A. Crafford ◽  
J. L. Glashow ◽  
D. Rankin ◽  
B. E. Sobel ◽  
...  
Keyword(s):  
Action Potentials ◽  
Extracellular Fluid ◽  
Ischemic Myocardium ◽  
Resting Membrane Potential ◽  
Phase 0 ◽  
Control Plasma ◽  
Maximum Rate Of Rise ◽  
Arrhythmogenic Effects

Lysophosphoglycerides accumulate in ischemic myocardium. To determine whether lysophosphatidylcholine (LPC) concentrations increase in extracellular fluid and may be arrhythmogenic, the anterior descending coronary artery of the open-chest cat (n = 12) was perfused with a Krebs-albumin solution after 10 min of ischemia and the effluent assayed for LPC. A twofold increase in LPC (0.097 +/- 0.02 to 0.170 +/- 0.03 mM) was observed. Microelectrode intracellular recordings from from normal feline endocardium at pH 7.4 in vitro revealed little change in action potentials when superfused with feline plasma despite augmented LPC to twice normal levels (0.74 mM). However, at pH 6.7, marked changes were elicited by LPC-enriched plasma including diminished resting membrane potential (-96 +/- 1 to -35 +/- 7 mV), amplitude (102 +/- 3 to 36 +/- 8 mV), maximum rate of rise (Vmax) of phase 0 (178 +/- 24 to 26 +/- 11 V/s), and conduction velocity with fractionation of the action potential. Acidified control plasma decreased only Vmax (from 161 to 57 V/s). Thus LPC increases twofold in effluents from cat myocardium in vivo after 10 min of ischemia and, coupled with ischemia-induced acidosis, is sufficient to induce marked electrophysiological derangements in vitro.

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