• The Korean Journal of Physiology and Pharmacology
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• v.17 no.4
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• pp.359-365
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• 2013

Plasma pH can be altered during pregnancy and at labor. Membrane excitability of smooth muscle including uterine muscle is suppressed by the activation of $K^+$ channels. Because contractility of uterine muscle is regulated by extracellular pH and humoral factors, $K^+$ conductance could be connected to factors regulating uterine contractility during pregnancy. Here, we showed that TASK-2 inhibitors such as quinidine, lidocaine, and extracellular acidosis produced contraction in uterine circular muscle of mouse. Furthermore, contractility was significantly increased in pregnant uterine circular muscle than that of non-pregnant muscle. These patterns were not changed even in the presence of tetraetylammonium (TEA) and 4-aminopyridine (4-AP). Finally, TASK-2 inhibitors induced strong myometrial contraction even in the presence of L-methionine, a known inhibitor of stretch-activated channels in myometrium. When compared to non-pregnant myometrium, pregnant myometrium showed increased immunohistochemical expression of TASK-2. Therefore, TASK-2, seems to play a key role during regulation of myometrial contractility in the pregnancy and provides new insight into preventing preterm delivery.

• Journal of Veterinary Clinics
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• v.17 no.2
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• pp.495-498
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• 2000

Leiomyosarcoma is defined as a malignant smooth muscle tumor or a tumor that arises from smooth muscle and it is found as firm. white and lobulated mass. Canine uterine Ieiomyosa- rcomas are rarely associated with clinical signs. We surveyed(one case which was treated at veter- inary medical leaching hospital of Seoul National University. Through this report we studied the meshed fur diagnosis of uterine leiomyosarcoma by symptom, hematological method and ultrahonog- raphy. To determine uterine leiomysarcoma is difficult due to similarity of clinical signs to pyometra. Especially symptoms could not be noticed even by dogs owners until dogs have an elevation of the number of white blood cells. We conclude ultrasonographic observation and experimental laparotomy are of great value to diagnose the uterine liomyosarcoma.

• The Korean Journal of Pharmacology
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• v.6 no.1
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• pp.37-44
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• 1970

The author studied the actions of autonomic drugs on the uterine muscle isolated from Ditrema temmincki Bleeker, and the results obtained were summerized as follows. 1) The motility of the fish uterus was stimulated by epinephrine, norepinephrine and phenylephrine, but inhibited by isoproterenol. 2) The inhibitory effects of isoproterenol on the fish uterus was not affected by phenoxybenzamine, but blocked by propranolol. 3) The excitatory effects of phenylephrine on the fish uterus were blocked by phenoxybenzamine, but stimulated by propranolol. 4) The excitatory effects of epinephrine and norepinephrine were reversed by phenoxybenzamine and stimulated by propranolol. 5) The motility of the fish uterus pretreated with phenoxybenzamine and propranolol was not affected by isoproterenol, phenylephrine, epinephrine and norepinephrine. 6) It seemed that the uterine muscle of the fish had both alpha excitatory and beta inhibitory receptors. 7) The motility of the uterus of the fish was stimulated by acetylcholine. The stimulating action of acetylcholine was antagonized by atropine. 8) The motility of fish uterus was not affected by nicotine and DMPP. The actions of these drugs were not affected by pretreatment with hexamethonium and atropine. 9) It is, therefore, concluded that there are not present ganglia cells furnished with cholinergic fiber in the uterine wall of the fish.

• The Korean Journal of Physiology
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• v.20 no.2
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• pp.199-208
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• 1986

The effects of $Mg^{++}$ upon the spontaneous contraction activated by 1 IU/l oxytocin were studied in the isolated rat uterine muscle. Longitudinal muscle strips u·ere prepared from the rat uteri at the estrous stage. 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) In the uterine strips contracting spontaneously, as $Mg^{++}$ concentration increased in the Tyrode solution the amplitude of peak tension decreased in all the experimental solutions containing the various concentrations of $Ca^{++}\;(0.5{\sim}4 mM)$. And the amplitude of peak tension increased in inverse proportion to the $[Mg^{++}]/[Ca^{++}]\; ratio$. It is suggested that the tension-lowering effect of $Mg^{++}$ would be developed through decreasing intracellular ionized free calcium ion concentration by uncertain mechanism. 2) The frequency of the uterine contraction activated by oxytocin increased as the $[Mg^{++}]/[Ca^{++}]\;ratio$ ratio increased up to 1/2, but the frequency decreased above this ratio. It is speculated that $Mg^{++}$ would influence the excitability control action of $Ca^{++}$.

• Journal of Veterinary Clinics
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• v.23 no.4
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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.

• Journal of Veterinary Clinics
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• v.33 no.3
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• pp.183-186
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• 2016

An 8-year-old, female lionhead rabbit with clinical sign of hematuria and vaginal discharge with/without blood was submitted to a local animal hospital. On exploratory laparotomy, three round to oval masses were observed in both uterine horns. The lumen of uterus was severely obstructed and distorted because of massive neoplastic proliferation. Histopathologically, the uterine masses revealed papillary projections along with irregular glandular structures into the lumen. The neoplastic foci were composed of numerous irregular sized neoplastic glands originated from uterine glands. These neoplastic cells showed very strong invasive tendency to muscle layer, therefore emboli of neoplastic cells were located in lymphatics. According to immunohistochemistry, the tumor cells in uterine masses demonstrated strong positive signals for cytokeratin, but negative for vimentin. Based on the gross, histopathologic and immunohistochemical features, this case was diagnosed as uterine adenocarcinoma in lionhead rabbit.

• Korean Journal of Veterinary Pathology
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• v.5 no.2
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• pp.71-74
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• 2001

Masses of the uterine cervix were detected from two dogs, being a 2-year-old female Yorkshire tarrier and a 12-year-old female Basset Hound. Grossly, the masses measuring 3.O$\times$3.O$\times$4.0 cm and 12.O$\times$l2.O$\times$10.07m were prominent, sharply circumscribed, fleshy tumors in the uterine cervix. Histologically, the masses consisted of smooth muscle cells interwoven in bundles, some of which were cut longitudinally (elongated nuclei) and others transversely. Tumor cell nuclei were ordinarily cigar shaped and had rounded blunt ends in the longitudinal plane. There were low mitotic figures without abnormal ones. From these results, these cases were diagnosed as leiomyoma of the uterine cervix. To our Knowledge, no similar tumors have been reported in the uterine cervix.

• Journal of Chest Surgery
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• v.23 no.3
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• pp.452-464
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• 1990

It is well known that extracellular Calcium plays a very important role in several steps of smooth muscle excitability and contractility, and there have been many concerns about factors influencing the distribution of extracellular Ca++ and the Ca++ flux through the cell membrane of the smooth muscle. Based on the assumption that Mg++ may also play an important role in the excitation and contraction processes of the smooth muscle by taking part in affecting Ca++ distribution and flux, many researches are being performed about the exact role of Mg++, especially in the vascular smooth muscle. But yet the effect of Mg++ in the smooth muscle activity is not clarified, and moreover the mechanism of Mg++ action is almost completely unknown. Present study attempted to clarify the effect of Mg++ on the excitability and contractility in the multiunit and unitary smooth muscle, and the mechanism concerned in it. The preparations used were the guinea-pig aortic strip as the experimental material of the multiunit smooth muscle and the rat uterine strip as the one of the unitary smooth muscle. The tissues were isolated from the sacrificed animal and were prepared for recording the isometric contraction. The effects of Mg++ and Ca++ were examined on the electrically driven or spontaneous contraction of the preparations. And the effects of these ions were also studied on the K+ or norepinephrine contracture. All experiments were performed in tris-buffered Tyrode solution which was aerated with 100% 02 and kept at 35oC. The results obtained were as follows: 1] Mg++ suppressed the phasic contraction induced by electrical field stimulation dose-dependently in the guinea-pig aortic strip, while the high concentration of Ca++ never recovered the decreased tension. These phenomena were not changed by the a - or b - adrenergic blocker. 2]Mg++ played the suppressing effect on the low concentration [20 and 40 mM] of K+-contracture in the aortic muscle, but the effect was not shown in the case of 100mM K+-contracture. 3] Mg++ also suppressed the contracture induced by norepinephrine in the aortic preparation. And the effect of Mg++ was most prominent in the contracture by the lowest [10 mM] concentration of norepinephrine. 4] In both the spontaneous and electrically driven contractions of the uterine strip, Mg++ decreased the amplitude of peak tension, and by the high concentration of Ca++ the amplitude of tension was recovered unlike the aortic muscle. 5] The frequency of the uterine spontaneous contraction increased as the [Ca++] / [Mg++] ratio increased up to 2, but the frequency decreased above this level. 6] Mg++ decreased the tension of the low[20 and 40mM] K+-contracture in the uterine smooth muscle, but the effect did not appear in the 100mM K+-contracture. From the above results, the following conclusion could be made. 1] Mg++ seems to suppress the contractility directly by acting on the smooth muscle itself, besides through the indirect action on the nerve terminal, in both the aortic and uterine smooth muscles. 2] The fact that the depressant effect of Mg++ on the K+-contracture is in inverse proportion to an increase of K+ concentration appears resulted from the extent of the opening state of the Ca++ channel. 3] Mg++ may play a depressant role on both the potential dependent and the receptor-operated Ca++ channels. 4] The relationship between the actions of Mg++ and Ca++ seems to be competitive in uterine muscle and non-competitive in aortic strip.

• Korean Journal of Veterinary Service
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• v.17 no.3
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• pp.255-263
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• 1994

To elucidate the action of the adrenergic nerve on the isolated uterine smooth muscle of the pig, effects of electrical transmural nerve stimulation and norepinephrine were investigated on the pretreatment of phentolamine ； non-selective ${\alpha}$-adrenoceptor blocker, propranolol ; ${\beta}$-adrenoceptor blocker and the yohimbine；${\alpha}_2$-selective adrenoceptor blocker from physiograph. 1. The relaxation response induced by norepinephrine was the concentration of $10^{-6}$ M at first and maximum response was concentration of $10^{-4}$M. 2. The relaxation response induced by norepinephrine was not effected by the pretreatment with non-selective $\alpha$-adrenoceptor blocker, phentolanune ($10^{-6}$ M) but was completely blocked by the pretreatment with ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M). 3. The contractile response induced by electrical transmural nerve stimulation(20V, 10Hz, 0.5msec, 20sec ) was inhibited by the pretreatment with non-selective ${\alpha}$-adrenoceptor blocker, phentolamine($10^{-6}$ M) but was not inhibited and rather increased by the pretreatment ${\beta}$-adrenoceptor blocker, propranolol($10^{-6}$ M), and was not approximately effected by the pretreatment with ${\alpha}_2$-adrenoceptor blocker, yohimbine($10^{-6}$ M). These finding suggest that it was excitatory action by ${\alpha}_1$-adrenergic nerve and inhibitory action by ${\alpha}_2$-adrenergic, ${\beta}$-adrenergic nerve on uterine smooth muscle of the pig.

• Clinical and Experimental Reproductive Medicine
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• v.30 no.3
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• pp.203-206
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• 2003

Objectives: Controversial arguments exists on both the case for and against on the accumulation of mitochondrial DNA (mtDNA) deletion in association to tissue and age. The debate continues as to whether this mutation is a major contributor to the phenotypic expression of aging and common degenerative diseases or simply a clinical insignificant epiphenomenon. The objective of this study was to determine whether the accumulation of mtDNA deletion is correlated with age-related and tissue-specific variation. Materials and Methods: One hundred and fifty-seven tissues from blood, ovary, uterine muscle, and abdominal muscle were obtained from patients ranging in age from 31$\sim$60 years. After reviewing the clinical reports, patients with mitochondrial disorder were excluded from this study. The tissues were obtained at gynecological surgeries with the consent of the patient. Total DNA isolated from blood, ovary, uterine muscle, and abdominal muscle was amplified by two rounds of PCR using two pairs of primers corresponding to positions 8225-8247 (sense), 13551-13574 (antisense) for the area around deleted mtDNA and 8421-8440 (sense), 13520-13501 (antisense) for nested PCR product. A statistical analysis was performed by $x^2$-test. Results: About 0% of blood, 94.8% of ovary, 71.4% of uterine muscle, and 86.1% abdominal muscle harbored mtDNA deletion. When we examined the proportion of deleted mtDNA according to age deletion rate was 90% of ovary, 63.6% of uterine muscle, 77.7% of abdominal muscle in thirties and 100% of all tissue in fifties. Conclusion: The findings of this study suggest that the mtDNA deletion is varied in tissue-specific pattern and increases with aging.