• The Korean Journal of Physiology
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• 제18권1호
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• pp.37-50
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• 1984

The effects of $Ca^{++}$ and its antagonists (verapamil and $La^{+++}$) upon the spontaneous contraction and the contracture induced by 60 mM K-Tyrode solution were studied in the isolated uterine muscle. Longitudinal muscle strips were prepared from the rat uteri at estrous stage. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% $O_2$ and kept at 35^{\circ}$. The results obtained were as follows: 1) In the uterine strips contracting spontaneously, both the amplitude of peak tension and the area of contraction curve increased dose-dependently in the range of $0.5${\sim}8$ mM $Ca^{++}$. The frequency of contraction increased as the concentration of $Ca^{++}$ increased up to 2 mM, but above this concentration the frequency decreased. In $Ca^{++}-free$ media, however, contraction did not develop. In the contracture induced by 60 mM K-Tyrode solution, the developed tension increased dose-dependently as the concentration of external $Ca^{++}$ increased to 8 mM. In the absence of external $Ca^{++}$ K-contracture appeared, but it was not sustained. 2) The spontaneous contraction of rat uterus was suppressed by verapamil in proportion to an increase of its concentration and totally abolished at the concentration of $3{\times}10^{-4}\;g/l$, but the spontaneous contraction re-appeared by addition of $Ca^{++}$. The amplitude of peak tension recovered completely but the recovery of frequency was incomplete. K-contracture decreased in a dose-dependent manner after the treatment with verapamil and totally disappeared at its concentration of $3{\times}10^{-4}\;g/l$. Even in this case contracture developed again by extra $Ca^{++}$. 3) The spontaneous contractile activity was inhibited by $La^{+++}$. At the concentration of $10^{-4}$M $La^{+++}$, fibrillation appeared. In the strip inhibited by $10^{-5}M\;La^{+++}$, contractility recovered completely by extra $Ca^{++}$ while in the $10^{-4}M\;La^{+++}$ treated preparation, the rhythmic spontaneous contraction did not develop even at the concentration of 16 mM $Ca^{++}$. After the initial transient depression of contracture tension by $10^{-3}M$ of $La^{+++}$, the strip stowed considerably large size of contracture, hardly influenced by external $Ca^{++}$ or verapamil. The results obtained in this experiment suggest that in the rat uterine muscle there would be some competitive actions between $Ca^{++}$ and its antagonists. It is speculated that $Ca^{++}$ plays an important role in the conduction of excitation, and $La^{+++}$ influences upon cellular $Ca^{++}$ mobilization and re-uptake process as well as transmembrane $Ca^{++}$ transport in a K-depolarized state.

• 한국임상수의학회지
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• 제23권4권
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• pp.421-426
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• 2006

The effects of transmural nerve stimulation induced releasing neurotransmitters on the changes of swine uterine smooth muscle motility were examined by polygraph through isometric force transducer. The frequency dependent relaxation and rebound contraction were revealed on precontraction with histamine by transmural nerve stimulation. The rebound contraction by transmural nerve stimulation was inhibited by nonselective ${\alpha}$-adrenergic receptor antagonist, phentolamine, and the relaxation by transmural nerve stimulation was blocked by nonselective ${\beta}$-adrenergic receptor antagonist, propranolol. The relaxation induced by nonselective ${\beta}$-adrenergic receptor agonist, isoproterenol on precontraction with histamine were the dose dependent manner and this relaxation was blocked by nonselective ${\beta}$-adrenergic receptor antagonist, propranolol in isolated uterine smooth muscle of pig. These results suggest that endogenous neurotransmitters on smooth muscle relaxation was influenced by ${\beta}$-adrenergic receptor in swine.

• Biomolecules & Therapeutics
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• 제5권3호
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• pp.292-298
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• 1997

General pharmacological properties of ι-muscone, the major component of musk, were investigatedin mice, rats and guinea pig. The administration of ι-muscone (1, 10, 100 mg/kg, p.o.) in mice had no effects in general behaviors, and no influences on analgesic actions and normal body temperature. Muscle relaxant action, intestinal propulsion and gastric secretion were not observed even at the high dose of 100 mg/kg. ι-Muscone (1, 10, 100 mg/kg, p.o.) given to conscious rats showed no effect on mean blood pressure and heart rate. It showed no direct effect at 2.4$\times$10.3 mg/ml and 2.4$\times$10-2 mg/ml in isolated uterus of rats and ileum of guinea pig, and also had no inhibition of contraction induced by oxytocin and histamine.

• 약학회지
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• 제14권1_2호
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• pp.21-27
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• 1970

Isoimperatorin and Oxypeucedanin isolated from root of Angelica Koreana Max. (Umbelliferae) that is used as "Kang-Whal" a botanical drug, in Korea, Show following general pharmacologic activities. The treatment with Oxypeucedanin on the exercised duodenum of the rabbit increased the motility of it while isoimperatorin shows little effects. But on the exercised heart of the frogs, both components depressed its contractility. Whereas Oxypeucedanin depressed both blood pressure of the carotied artery and respiration of the rabbit, Isoimperatorin tends to increase blood pressure, respiration and the tonus of the muscle of the earth worm. Oxypeucedanin did not affect the tonus of the muscles of the earth worm, but depressed the uterus contraction of the rabbit, which was, on the contrary, increased by Isoimperatorin.

• 생약학회지
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• 제2권1호
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• pp.15-18
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• 1971

The histological structures of Buxus koreana were studied by cross section and compared with those of Buxus koreana var. elongata, B. koreana var. insularis, B. microphylla subsp. sinica (Taiwan) and B. liukiuensis(Okinawa). Many different points showed that B. koreana var. insularis is similar to B. microphylla subsp. sinica while B. koreana to B. liukiuensis. The extracts of Buxus koreana by three solvents are as follows: ether ext. 3.34%, dilute alcohol ext. 16.98%, water ext. 11.67%. The total alkaloid of Buxus koreana is approximately 0.01%. The general pharmacological effects of dilute alcohol ext. of Buxus koreana were studied and the following conclusions were obtained. Contraction of excised uterus of rabbit was augmented by treatment of dilute alcohol ext. Motility of excised intestine of rabbit was stopped for a moment and stimulated at once by treatment of dilute alcohol ext.

• Journal of Pharmaceutical Investigation
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• 제14권2호
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• pp.86-91
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• 1984

A ginseng preparation (GP) consisting of ginseng ex., lycium fructus ex., four kinds of vitamines and caffein was evaluated for acute toxicity and general pharmacology. Average lethal doses $(LD_{50})$ of GP in male mice were 2,988mg/kg (i.p.) and more than 3g/kg (p.o.). In dosage of 300 and 900mg/kg (p.o.) showed no analgesic activity in both tests of the writhing method induced by acetic acid and of tail pressure method and no effect on the pentetrazole-induced convulsion. However, it appeared to have a hypothermic action only in dose of 900mg/kg. The duration of hypnosis induced by hexobarbital sodium in mice was shortened by GP, being probably due to caffein. GP Produced no marked contraction of isolated ileum and uterus in high concentrations of up to $1{\pm}10^{-3}g/ml$. These results suggested that GP did not show any considerable central nervous depressant activity and exhibited very weak actue toxicity in mice.

• 한국가축번식학회지
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• 제19권4호
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• pp.245-250
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• 1996

This study was undertaken to illustrate the uterotonic effect of Leonurus sibiricus. It was dissolved in sterile water and several different dosages were administered both in vitro and in vivo study. Rat uterine tissue for in vitro bioassay was obtained from estrous rat. From the low to high dosages of Leonurus sibiricus were tried and each uterine contraction was recorded and integrated. Anesthetized estrous rat for in vivo study was cannulated into the jugular vein for infusion of the compound. Another cannula with a balloon tipped and water filled was inserted into the uterus to measure uterine activity. While the uterine tissue did not respond to low dosage of compound, high dosage of compound stimulated the tissue to contract less than 1 minute with low amplitude. In vivo rat uterus showed a certain, consistent pattern of contractions which was initial relaxation and followed by prolonged and increased amplitude of contractions. It also caused a short breathing stop which might be due to acute acidosis.

• 대한수의학회지
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• 제22권1호
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• pp.1-8
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• 1982

The effect of acetylcholine, oxytocin and prostaglandin $F_{2{\alpha}}$ ($PGF_{2{\alpha}}$) on cyclic nucleotide levels in estrogen-primed rabbit whole uterus were studied in the presence and absence of 1-methyl-3-isobutyl xanthine (MIX), a phosphodiestrase inhibitor, and indomethacin, a prostagandin inhibitor. In the absence of MIX, acetylcholine increased guanosine 3', 5'-cyclic monophosphate (cGMP), but had no effect on adenosine 3', 5'-cyclic monophosphate (cAMP) levels. In contrast, oxytocin had no influence on cGMP, but decreased cAMP levels. $PGF_{2{\alpha}}$ increased cGMP and decreased cAMP levels. MIX increased both cAMP and cGMP levels. Oxytocin and $PGF_{2{\alpha}}$ further increased cGMP levels, indicating activation of guanylate cyclase activity. The ratio of cAMP/cGMP was decreased by uterine stinulants both in presence and absence of MIX. Indomethacin elevated cAMP and cGMP revels. The effects of uterine stimulants in the presence of indomethacin on cyclic nucleotide levels were varied from tissue to tisse. In general, oxytocin decreased cGMP and $PGF_{2{\alpha}}$ increased cAMP/cGMP levels, but the effects were statisically nonsignicficant. The cAMP/cGMP ratio was increased by uterine stimulant in the presence of indomethacin. In conclusion, uterine stimulants eased cAMP/cGMP ratio which indicates that the uterine stimulants have opposing effects on adenylate cyclase and guanylate cyclase activities. The endometrium plays a role in the regulation of cyclic nucleotide levels and uterine contraction by means of PG synthesis. Indomethacin has an unknown activities besides both of PG synthetase and phosphodiesterase inhibitions.

• 셀메드
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• 제10권1호
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• pp.2.1-2.8
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• 2020

Uterotonics have the ability to contract uterus. Such plants might be useful in augmenting or inducing labour, expelling retained afterbirth and for abortifacient purposes. Limitations associated with conventional treatments have made herbal medicines a feasible alternative for the management of these conditions. The aim of this study was to evaluate the contractile effects of Uvariodendron kirkii extracts on isolated uterine strips of female Wistar rats. Isolated strips of Wistar rats' uteri were treated with 20, 40, 80 and 160 mg/ml concentrations of Uvariodendron kirkii aqueous extract. The plant extract was also tested against prostaglandin and oxytocin induced uterine contractions. Uvariodendron kirkii extract concentrations (20, 40, 80 and 160 mg/ml) increased the frequency of uterine contraction (16.53, 25.12, 33.48 and 56.39 percentages respectively) compared to the control. The graded extract concentrations caused a significant increase in amplitude (force) of uterine contractions by 2.87, 9.22, 16.37 and 24.32 percentages respectively. The concentrations significantly increased the frequency of oxytocin induced uterine contractions by 6.92; 28.31; 47.06, 58.78 percentages respectively. The graded extract concentrations also significantly increased the amplitude of oxytocin induced uterine contractions by 6.07; 9.40; 15.19 and 23.56 percentages respectively. Uvariodendron kirkii extract concentrations significantly increased the frequency and amplitude of prostaglandin induced contractions. The percentage increase in frequency was 11.44, 8.92, 20.65 and 35.71 at 20, 40, 80 and 160 mg/ml respectively. The mean amplitude of prostaglandin induced uterine contractions also increased (4.75, 3.89, 8.29 and 15.91% at 20. 40, 80 and 160 mg/ml respectively). The extract caused a dose dependent increase in uterine frequency and amplitude of contraction. The findings of thisstudy are useful in generating a novel uterotonic agent that will be useful in augmenting labour or in expelling retained after birth in cattle. More studies at molecular level will further elucidate the plant mechanism of action.

• Clinical and Experimental Reproductive Medicine
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• 제15권2호
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• pp.93-102
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• 1988

These studies were undertaken to examine the relationship between tamoxifen and sex steroid hormones in rat uterine morphology and the effect of tamoxifen on sex steroid hormone levels, implantation and myometrial contraction. The results obtained were as follows : 1) The increase in height of the luminal epithelium caused by tamoxifen treatment was blocked by progesterone. The increase in height of luminal epithelium caused by $estradiol-17{\beta}$ treatment was blocked by tamoxifen. 2) When a single dose of tamoxifen(10, 20, $40{\mu}g$) was given on Day 2 of pregnancy, implantation was prevented. Plasma $estradiol-17{\beta}$ level fell in a dose-dependent manner but plasma progesterone level was constant. 3) In vitro, tamoxifen decreased rat uterine contractility in a dose-dependent manner.