• The Korean Journal of Physiology
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• v.17 no.2
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• pp.135-142
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• 1983

$PGE_2$ and $PGF_{2{\alpha}}$ are known to act similarly in a number of animal tissues. They both facilitate regression of corpus luteum(Poyser, 1972; Fuch et al, 1974; Coudert et at, 1974) and stimulate contraction of uterine muscle (Laudanski et al, 1977; Porter et al, 1979; Hollingsworth et al, 1980). It is, however, not known whether these two prostaglandins exert similar actions in osmotic fragility of erythrocytes (Rasmussen et al, 1975) and $PGF_{2{\alpha}}$ alters conformation of membrane proteins (Meyers aud Swislocki, 1974). The former effect may not be mediated through changes in c- AMP concentration in the cell, since the adenylate cyclase activity in human erythrocyte is extremely low (Rodan et al, 1976; Sutherland et al, 1962) and the latter effect implies that physical state (or fluidity) of the membrane is altered by $PGF_{2{\alpha}}$. The present study was undertaken to elucidate mechanisms of action of $PGE_2$ and $PGF_{2{\alpha}}$ on the human erythocyte membrane by examining their effects on osmotic fragility and $Ca^{++}$ binding to the membrane fragments. The results are summarized as follows: 1) $PGE_2$ and $PGF_{2{\alpha}}$ increased osmotic fragility at concentrations above $10^{11}\;M$, the effect being similar for both hormones. The concentration of NaCl for 100% hemolysis was $1/16{\sim}1/17\;M$ in the presence of $10^{11}\;M\;PGE_2$ or $PGF_{2{\alpha}}$ and 1/18 M in the absence of the hormone (control). 2) When erythrocytes were suspended in 1/15 M NaCl solution, $44.2{\pm}4.3%$ of cells were hemolyzed. Addition of $10^{12}\;M\;PGE_2$ or $PGF_{2{\alpha}}$ did not increase hemolysis. When the concentration of the hormones was increased to $10^{11}\;M$, however the degree of hemolysis increased markealy to about 80%. No further increase in hemolysis was observed at concentration of the hormones above $10^{11}\;M$. 3) The additional hemolysis due to $10^{11}\;M\;PGE_2$ and $PGF_{2{\alpha}}$ appeared to he identical regardless of absence or presence of $Ca^{++}\;(0.5{\sim}10\;mM)$ in the suspending medium. 4) In the absence of prostaglandin, the binding of $Ca^{++}$ to the erythrocyte membrane increased curvilinearly as the $Ca^{++}$ concentration increased up to 5 mM above which it leveled off. A similar dependence of $Ca^{++}$ binding on the $Ca^{++}$ concentration was observed in the presence of $10^{11}\;M\;PGE_2$ or $PGF_{2{\alpha}}$, however, the amount of $Ca^{++}$ bound at a given $Ca^{++}$ concentration was significantly higher than in the absence of the hormones. 5) As in the hemolysis, $PGE_2$ and $PGF_{2{\alpha}}$ did not affect the $Ca^{++}$ binding at a concentration of $10^{12}\;M$, but increased it by about 100% at concentration above $10^{11}\;M$. These result indicate that both tile osmotic fragility of erythrocyte and the $Ca^{++}$ binding to the erythrocyte membrane are similarly enhanced by $PGE_2$ and $PGF_{2{\alpha}}$, but these two effects are not causally related. It is, therefore, concluded that the prostaglandin-induced hemolysis is not directly associated with alterations of the $Ca^{++}$ content in the membrane.

• The Korean Journal of Physiology
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• v.9 no.1
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• pp.13-22
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• 1975

From the study of movements of $Ca^{++}$ in frog cardiac muscle, Niedergerke (1963) postulated that $Ca^{++}$ necessary for the cardiac contraction is stored in a specific pool. Langer et al (1967) and DeCaro (1967) also found a close relationship between the change of $Ca^{++}$ flux kinetics and the change of contractile force. According to the studies of several investigators, Ca II (Bailey and Dressel 1968) or phase I and II (Langer 1965, Langer et al 1967, 1971) in the $Ca^{++}$ washout curve was associated with cardiac contractility. This investigation was aimed to elucidate the anatomical region of the contractile active $Ca^{++}$ pool. At the same time, it was assumed in this study that $Ca^{++}$ in the sarcoplasmic reticulumn represents one of the major intracellular $Ca^{++}$ pool and cardiac contractility was also dependent on the intracellular $Ca^{++}$ concentration. Consequently, this experiment was performed at different temperatures to activate to activate inhibit the deactivating process of activated $Ca^{++}$ in the intracellular space to see if changes in the contractility decay curve existed at different temperatures. The isolated hearts of rabbits and turtles (Amyda maackii) were attached to the perfusion apparatus according to the method employed by Bailey and Dressel (1968). The isolated hearts were initally perfused with a full Ringer solution containing 2 mg/ml of inulin for 1 hr, and then $Ca^{++}$ and inulin-free Ringer solution was perfused while the isometric tension was recorded and a serial sample of perfusion fluid dripping from the cardiac apex was collected for 10 sec throughout experimental period. The above procedure was performed at $23^{\circ}C$, $30^{\circ}C$ and $38^{\circ}C$ on the rabbit heart and $10{\sim}13^{\circ}C$, $10^{\circ}C$, $25^{\circ}C$, $30^{\circ}C$ and $35^{\circ}C$ on the turtle heart. After determination of $Ca^{++}$ and inulin concentration of the samples, the $Ca^{++}$, inulin washout curve and the contractile tensin decay curve were analysed according to the method of Riggs (1963). The results were summarized as follows; 1. In the rabbit heart, there are 2 inulin compartments, 3 $Ca^{++}$ compartments and sing1e exponential decay of contractile tension. In the turtle heart, there are $1{\sim}2$ inulin compartments, $1{\sim}2$ $Ca^{++}$ compartments and $1{\sim}2$ phases of contractile tension decay. The fact that the inulin space was divided into 3 compartments in the washout curve in these hearts indicates the presence of heterogeneity in cardiac perfusion, i.e., overfused and underperfused area. 2. Ca I a9d Ca II in these hearts were found to have $Ca^{++}$ in the ECF compartments because their half times in the washout curves were far smaller than those of the inulin washout curves in the rabbit heart and similar to those of the inulin washout curves in the turtle heart. Ca III in the rabbit heart may have originated from the intracellular $Ca^{++}$ store. But no Ca III in the turtle heart was found. This may be due to the fact that the iutracellular $Ca^{++}$ pool in the turtle heart was too small to detect using this experimental procedure since sarcoplasmic reticulumn in the turtle heart is poorly developed. 3. In the rabbit heart, there were no chages in the half time of Ca I, Ca II, inulin I and inulin II at different temperatures, but the half time of Ca III was significantly prolonged at lower temperatures, and the half time of the contractile tension decay tended to be prolonged at lower temperatures but this was not significant. In the turtle heart, there were no changes in the half time of Ca I, Ca II, inulin 1, inulin II and phase I of the contractile tension decay at different temperatures, but the half time of phase II of the contractile tension decay was significantly prolonged at lower temperatures. This finding indicates that intracellu!ar $Ca^{++}$ in these hearts was also responsible particulary for maintaining the cardiac contractility at the lower temperatures. 4. The half times of contractile tension decay were shorter than those of Ca II in the $Ca^{++}$ washout curves in both animal hearts. According to the above results it was shown that $Ca^{++}$ in ECF is primarily and $Ca^{++}$ in the intracellular space is partially associated with the cardic contractility.

• The Korean Journal of Physiology
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• v.22 no.2
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• pp.189-206
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• 1988

The effects of ouabain on the contractile and electrical activities were investigated in the isolated preparations of guinea-pig taenia coli, and compared with those of vanadate. Spontaneous contractions were recorded with force transducer, and electrical activites were measured by use of suction electrode, or single sucrose-gap technique. The contractions were induced by the electrical stimulation for 5 seconds every 1 minute with alternating current (60 Hz, 3.0 V/cm) through the platinum electrodes located in parallel with the long axis of the preparation. All experiments were performed in tris-buffered Tyrode solution which was aerated with $100%{\;}O_2$ and kept at $35^{\circ}C$. The results obtained were as follows: 1) Responses of spontaneous contractions to ouabain were concentration-dependent; $10^{-7}M$ ouabain caused a rise of basal tone. Above the concentration of $10^{-6}M$ ouabain, an initial increase followed by a decrease in tension was observed. 2) A continuous spike discharge was induced by the administration of $10^{-7}M$ ouabain. Above $10^{-6}M$ ouabain, a transient initial increase followed by a decrease in spike frequency and amplitude was produced, and finally membrane potential was sustained at a certain level without a spike discharge. 3) The characteristic response to $10^{-7}M$ ouabain was not blocked by the pretreatment with $10^{-7}M$ atropine. 4) The electrically induced contractions were completely suppressed at the concentration of $2{\times}10^{-7}M$ ouabain. These contractions were blocked more rapidly in paralled with the increase in ouabain concentration. 5) Effects of vanadate on the spontaneous activities were quite different from those of ouabain; $10^{-6}M$ vanadate increased the amplitude of contractions and $10^{-5}M$ vanadate increased slightly both amplitude and frequency of spontaneous contractions. $10^{-4}M$ vanadate showed irregular phasic contractions superimposed on the increased basal tone. 6) $10^{-5}M$ vanadate depolarized the membrane potential and shortened the interval between the bursts of spike discharge, whereas $10^{-4}M$ vanadate induced continuous spike discharge with membrane depolarization. 7) Vanadate caused a characteristic inhibitory response to the contractions induced by electrical stimulation; An initial rapid inhibition of tension development and then gradual recovery to a certain level. From the above results, the following conclusions could be made: 1) The rise of basal tone at $10^{-7}M$ ouabain is due to continuous spike discharge without a silent period. The continuous spike discharge is likely to be associated with a slight membrane depolarization caused by the blockage of Na pump. 2) The biphasic response induced by above $10^{-6}M$ ouabain seems to occur by the different mechanisms. The initial increase in tension is associated with depolarization along with an increase in spike frquency, whereas the subsequent relaxation occurs through a non-electrical mechanism. 3) The characteristic response to $10^{-7}M$ ouabain is resulted not from the action on intrinsic nerve terminal, but from its direct action on the membrane of smooth muscle cells. 4) The phasic contractions superimposed on the increased basal tone at the concentration of $10^{-4}M$ vanadate is resulted from the continuous spike discharge with membrane depolarization, of which mechanism remains unknown. 5) The inhibitory action of ouabain on the electrically induced contractions suggests that the increasein intracellular Na in some way inhibits the electrically induced $Ca^{2+}$ influx. The mechanism of vanadate action on the induced contractions remains unknown.

• Journal of Acupuncture Research
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• v.22 no.3
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• pp.123-135
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• 2005

Objective : The aim of this study was to rivew systemically literature and clinical trials in the treatment of urinary incontinence or lower urinary tract syndrome(LUTS). Methods : Computerized literature searches were carried out on two electronic database, and computerized searching on some korea oriental medicine journals in library of Kyung-Hee Medical center. Results : 1. Three reports of review study, six reports of experimental study and fourteen reports of clinical trials were collected and reviewed. Three reports of review study were all printed in the korea oriental medicine journal. From 2000, researches and studies have been increased in quantity and improved in quality. 2. Urinary disturbance include variable symptoms of lower urinary tract symptoms, urinary incontinence, in theaspect of Oriental medicine these symptoms are anurin, dysuria, urinary incontinence, nochumal enuresis, uracratia and so on. 3. Roughly physiological procedure of Acupuncture in Treatment of Urianry Disturbance may be that effect of acupuncture stimulation for parasympathetic nerve, sleep-arousal system in cerebrum, pontine/spinal urination center and pudendal/pelvic nerve affect bladder in expansion of bladder capacity, inhibition of urinary contraction and affection in periurethral muscle by continuous excitement of spinal annular circuit and synapse of neuron. 4. Clinical result for acupuncture treatment in urinary disturbance is summarized that acupuncture treatment in urianation disturbance of Neurogenic Bladder, Incontinence, Cycitis, Nocturnal Enuresis, Prostatitis/Pelvic Pain Syndrom and so on is significant clinical trials and technique. Conclusion : Hereafter, in the old age society these variable urinary disturbance patients are increased and desire of treatment may be also increased. So study of various and formal treatment and tecnnique is needed.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.723-735
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• 1998

Background : Vitamin C has been reported to have a role in the decrease of airway hyperresponsiveness in animal models. This data is based on some metabolic actions of vitamin C, such as promotion of histamine degradation, producing more $PGE_2$ than $PGF_{2\alpha}$ in cyclooxygenase pathway, decrease of smooth muscle contraction, and acting as reducing agent of oxidant. It has been also known that heavy smokers have lower blood levels of vitamin C than nonsmokers and this deficiency in heavy smokers have been explained by several mechanisms, such as increased oxidation by oxidants and free radicals, increased biosynthesis of catecholamine and serotonin released by nicotine, and inadequate dietary intake. In this study, We attempted to assess effect of vitamin C on bronchial hyperresponsiveness in heavy smokers who have bronchial hyperresponsiveness and role of vitamin C on bronchial hyperresponsiveness. Method: To assess acute effect of vitamin C on airway hyperresponsiveness, blood sample for vitamin C level and spirometry, methacholine challenge test were done in 17 smokers and 8 nonsmokers, and one hour after oral administration of vitamin C 3 g, blood sample for vitamin C level and spirometry, methacholine challenge test were repeated. To assess chronic effect of vitamin C on airway hyperresponsiveness, after daily administration of vitamin C 1 g for one week in 17 smokers, blood sample for vitamin C level and spirometry, methacholine challenge test were done. To assess role of vitamin C, after oral administration of vitamin C 3 g plus indomethacin 100 mg in 12 of 15 smokers who were reactive to methacholine challenge test, spirometry and methacholine challenge test were done and after oral intake of indomethacin 100 mg in 12 smokers who were reactive to methacholine challenge test, spirometry and methacholine challenge test were repeated. Result: There were no significant differences in whole blood vitamin C levels between smokers($1.17{\pm}0.22$ mg/dL) and nonsmcikers($1.14{\pm}0.19$ mg/dL) (p>0.05). Fifteen of the 17 smokers(88.2%) were reactive to methacholine challenge test and 10 of the 15 smokers who were reactive to methacholine challenge test were less than 8 mg/dL in $PC_{20}FEV-2$, and 7 of the 8 nonsmokers(87.5%) were nonreactive to methacholine challenge test There were significant decrease in bronchial responsiveness after oral administration of vitamin C 3 g in 13 of the 15 smokers who were reactive to methacholine challenge test This significant decrease persisted with maintenance daily administration of 1 g for one week. $PC_{20}FEV-2$ were not correlated to vitamin C levels in smokers. After oral administration of indomethacin 100 mg, significant reduction of bronchial responsiveness that occured after oral administration of vitamin C 3 g in smokers were attenuated. Conclusion: Although there were no significant differences in whole blood vitamin C levels between smokers and nonsmokers. heavy smokers have significant increase in bronchial responsiveness than nonsmokers. This bronchial hyperresponsiveness of heavy smokers can be attenuated by vitamin C supplement. Disappearance of vitamin C effect by indomethacin supplement may suggest that vitamin C exert its effect via alteration of arachidonic acid metabolism.