• Title/Summary/Keyword: pH stimulation

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THE STUDY ON THE EFFECTS OF THE INSULIN-LIKE GROWTH FACTOR-I ON THE BIOLOGICAL ACTIVITY OF THE HUMAN PERIODONTAL LIGAMENT CELLS (Insulin-like growth factor-I 이 치주인대세포의 생물학적 활성도에 미치는 영향에 대한 연구)

  • Kim, Seong-Jin;Lee, Jae-Mok;Suh, Jo-Young
    • Journal of Periodontal and Implant Science
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    • v.24 no.2
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    • pp.219-237
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    • 1994
  • The ultimate goal of clinical periodontal therapy is to achieve regeneration of a healthy connective tissue reattachment. Conventional therapy including scaling, root planing, gingival curettage, gingivectomy and flap procedures of various types results primarily in repair rather than regeneration of the periodontium. In order for periodontal regeneration to occur, progenitor periodontal ligament cells must migrate to the denuded root surface, attach to it, proliferate and mature into an organized and functional fibrous attachment apparatus. Polypeptide growth factors belong to a class of potent biologic mediators which regulate cell differentiation, proliferation, migration and metabolism. Insulin-like growth factor-I (IGF- I ) of these factors appear to have an important role in periodontal wound healing and bone formation. The purpose of this study is to evaluate the effects of IGF- I on the periodontal ligament cells to use as a regeneration promoting agent of periodontal tissue. Human periodontal ligament cells were obtained from periodontal tissue explants culture of the first premolar tooth extracted for the orthodontic treatment. Cells were cultured in Dulbecco's modified Eagle medium(DMEM) with 10% fetal bovine serum. Fourth to seventh passage cells were plated in 24 well tissue culture plates and medium changed to serum-free medium prior to addition of growth factors. Cell proliferation was measured by the incorporation of $[^3H]-thymidine$ into DNA, Protein synthesis was determined by measurement of $[^3H]-proline$ incorporation into collagenase-digestible protein(CDP) and noncollagenous protein(NCP) according to the method of Peterkofsky and Diegelmann (1971), And alkaline phosphatase activity was measured as one parameter of osteoblastic differentiation. The results were as follows : The DNA synthetic activity was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I At the concentration of 10, 100ng/ml, IGF- I significantly increased the DNA synthetic activity(P<0.05) The total protein, collagen and noncollagen synthesis was increased in a dose-dependent manner with IGF- I except for 0.1ng/ml concentration of IGF- I. At the concentration of 1, 10, 100ng/ml, IGF- I significantly increased the total protein, collagen and noncollagen synthesis activity(P<0.95, P<0.001). The % of collagen was not effected according to the concentration of IGF- I. The alkaline phosphatase activity was increased in a dose-, time-dependent manner with IGF- I (10, 100ng/ml). In conclusions, the present study shows that IGF- I has a potentiality to enhance the DNA synthesis of periodontal ligament cells with including the increase of the total protein and collagen synthetic activity. The use of IGF- I to mediate biological stimulation of periodontal ligament cells shows promise for future therapeutic applications.

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Effect of Resistant Starch on the Large Bowel Environment and Plasma Lipid in Rats with Loperamide-Induced Constipation (저항전분 투여가 Loperamide 유도 변비 쥐의 대장환경과 혈청지질에 미치는 효과)

  • Sin, Hyun-Ju;Kim, Kwang-Ok;Kim, Sung-Hong;Kim, Young-Ah;Lee, Hye-Sung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.39 no.5
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    • pp.684-691
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    • 2010
  • The present study was conducted to evaluate the effect of resistant starch (RS) on the large bowel function and plasma lipids in rats with constipation induced by Loperamide. Animals were divided into six groups: normal control-5% cellulose, constipation-5% cellulose, constipation-5% pectin, constipation-5% RS-type 2 (RS2), constipation-8% RS2 and constipation-5% RS type 3 (RS3) groups, and fed experimental diets for five weeks. The results from RS groups were compared with those from other dietary fiber groups. The groups supplemented with RS3 or high level of RS2 showed significantly increased counts of bifidobacteria in the cecum than the other groups. The production of total short chain fatty acids in the cecal contents was significantly high in pectin, RS3 and high RS2 groups. The pH in the cecal contents of the RS supplemented groups was significantly decreased compared with the cellulose supplemented groups. The production of prostaglandin E2 in the colon mucus of the RS groups was higher than the normal group; however, it was significantly decreased compared to the cellulose or pectin supplemented constipated groups. The thickness of the mucus layer and the production of mucus from epithelial cells were significantly increased in RS3 group compared to the constipated cellulose group. Supplementation of resistant starch significantly elevated the ratio of HDL-cholesterol to total cholesterol and significantly lowered plasma atherogenic index compared with cellulose or pectin supplementation in constipated rats. The results of the present study demonstrated that resistant starch supplementation may help in improving the large bowel environment by stimulation of bifidobacterial proliferation, reduction of pH and inflammation factor and by increased production of mucus. It has also been found that an additional health benefit is improvement in lipid levels of serum.

Cloning, Expression and Hormonal Regulation of Steroidogenic Acute Regulatory Protein Gene in Buffalo Ovary

  • Malhotra, Nupur;Singh, Dheer;Sharma, M.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.2
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    • pp.184-193
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    • 2007
  • In mammalian ovary, steroidogenic acute regulatory (StAR) protein mediates the true rate-limiting step of transport of cholesterol from outer to inner mitochondrial membrane. Appropriate expression of StAR gene represents an indispensable component of steroidogenesis and its regulation has been found to be species specific. However, limited information is available regarding StAR gene expression during estrous cycle in buffalo ovary. In the present study, expression, localization and hormonal regulation of StAR mRNA were analyzed by semi-quantitative RT-PCR in buffalo ovary and partial cDNA was cloned. Total RNA was isolated from whole follicles of different sizes, granulosa cells from different size follicles and postovulatory structures like corpus luteum and Corpus albicans. Semi-quantitative RT-PCR analyses showed StAR mRNA expression in the postovulatory structure, corpus luteum. No StAR mRNA was detected in total RNA isolated from whole follicles of different size including the preovulatory follicle (>9 mm in diameter). However, granulosa cells isolated from preovulatory follicles showed the moderate expression of StAR mRNA. To assess the hormonal regulation of StAR mRNA, primary culture of buffalo granulosa cells were treated with FSH (100 ng/ml) alone or along with IGF-I (100 ng/ml) for 12 to 18 h. The abundance of StAR mRNA increased in cells treated with FSH alone or FSH with IGF-I. However, effect of FSH with IGF-I on mRNA expression was found highly significant (p<0.01). In conclusion, differential expression of StAR messages was observed during estrous cycle in buffalo ovary. Also, there was a synergistic action of IGF-I on FSH stimulation of StAR gene.

Wild Ginseng Attenuates Anxiety- and Depression-Like Behaviors During Morphine Withdrawal

  • Lee, Bom-Bi;Kim, Hyuk;Shim, In-Sop;Lee, Hye-Jung;Hahm, Dae-Hyun
    • Journal of Microbiology and Biotechnology
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    • v.21 no.10
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    • pp.1088-1096
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    • 2011
  • The purpose of this study was to evaluate whether wild ginseng (WG) administration could attenuate anxiety- and depression-like behaviors and expression of corticotrophin-releasing factor (CRF) and neuropeptide Y (NPY) following withdrawal from repeated morphine administration in rats. Male rats were administered daily doses of WG (50, 100, or 200 mg/kg, i.p.) for 5 days, 30 min before morphine injection (40 mg/kg, s.c). The anxiety- and depression-like behavioral responses were measured 72 h after the last morphine injection using an elevated plus maze (EPM) and forced swimming test (FST), respectively. Changes in hypothalamic CRF and NPY expressions were also examined by analyzing their immunoreactivities in the hypothalamus. Daily administration of WG significantly reduced anxiety- and depression-like behavior, and elicited the suppression of CRF expression and the stimulation of NPY expression in the hypothalamus. Our results demonstrated that WG extract might be effective at inhibiting the anxiety and depression responses due to morphine withdrawal by possibly modulating the hypothalamus CRF and NPY systems. Furthermore, these findings imply that WG extract can be used for developing new medication to cure or alleviate morphine withdrawal symptoms and to prevent relapses of morphine use.

Effect of $Ca^{2+}-channel$ Blockers on Norepinephrine Release in the Rat Hippocampal Slice and Synaptosome

  • Kim, Suk-Won;Jung, Kyu-Yong;Choi, Bong-Kyu
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.2
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    • pp.87-91
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    • 2002
  • The aim of this study was to investigate the role of $Ca^{2+}-channel$ blockers in norepinephrine (NE) release from rat hippocampus. Slices and synaptosomes were incubated with $[^3H]-NE$ and the releases of the labelled products were evoked by 25 mM KCl stimulation. Nifedipine, diltiazem, nicardipine, flunarizine and pimozide did not affect the evoked and basal release of NE in the slice. But, diltiazem, nicardipine and flunarizine decreased the evoked NE release with a dose-related manner without any change of the basal release from synaptosomes. Also, a large dose of pimozide produced modest decrement of NE release. ${\omega}-conotoxin$ (CTx) GVIA decreased the evoked NE release in a dose-dependent manner without changing the basal release. And ${\omega}-CTxMVIIC$ decreased the evoked NE release in the synaoptosomes without any effect in the slice, but the effect of decrement was far less than that of ${\omega}-CTxGVIA.$ In interaction experiments with ${\omega}-CTxGVIA,\;{\omega}-CTxMVIIC$ slightly potentiated the effect of ${\omega}-CTxGVIA$ on NE release in the slice and synaptosomal preparations. These results suggest that the NE release in the rat hippocampus is mediated mainly by N-type $Ca^{2+}-channels,$ and that other types such as L-, T- and/or P/Q-type $Ca^{2+}-channels$ could also be participate in this process.

Association of Backfat Thickness with Postheparin Lipoprotein Lipase Activity and Very Low Density Lipoprotein-Subfractions in Growing Pigs

  • Loh, T.C.;Lean, I.J.;Dodds, P.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.11
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    • pp.1592-1597
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    • 2001
  • Sixteen pigs from 2 distinct genetic lines (LGAH and VFIL) obtained after eight generations of divergent selection for high (H) and low (L) lean tissue growth rate with ad-libitum feeding (LGA) and voluntary feed intake (VF1), respectively, were used in this study. The objectives of this investigation were to establish appropriate working conditions for the postheparin plasma lipoprotein lipase (LPL) assay and to study relationships between fat deposition and plasma lipids, very low density lipoprotein (VLDL) lipids, VLDL-subfractions and postheparin plasma LPL activity in growing pigs. Four preliminary experiments were performed to determine the appropriate working conditions for the postheparin plasma LPL assays. Postheparin plasma preincubated with SDS (20-50 mM) at $26^{\circ}C$ for 45 minutes inhibited hepatic lipase activity. A total of $2{\mu}l$ VLDL/assay produced maximum stimulation of LPL activity. Postheparin plasma protein and increasing incubation time contributed an optimum response. LGAH pigs had a significantly higher proportion subtraction 2 than VFIL pigs. No differences were observed in postheparin plasma LPL activity and backfat thickness for two lines of pigs. There were positive correlations between backfat thickness and proportion of subtractions 2 and postheparin plasma LPL activity but the results were not statistically significant. Backfat thickness was not statistically correlated with proportion of subtraction 2 and postheparin plasma LPL activity in a multiple regression analysis. It is believed that the apolipoprotein E, which is present in higher quantities in VLDL-subfraction 2 plays an important role for clearing VLDL triacylglycerol into adipose tissue. LPL activity of pigs can be measured by using postheparin plasma technique. If the relationships of backfat thickness and VLDL-subfraction 2 and postheparin plasma LPL activity can be established, it suggests that these parameters could be used as indicators in selection programmes. Further experiments need to be conducted by using larger sample size and different breed of pigs with greater differences in backfat thicknesses to confirm these trends.

Comparison of EMG and Muscle Reaction Force to Detect Exercise Intention (운동의도 검출을 위한 근육반력과 근전도의 비교)

  • Heo, J.H.;Kim, J.W.;Kwon, Y.R.;Eom, Gwang-Moon;Jeong, K.Y.;Kwon, D.K.
    • Journal of Biomedical Engineering Research
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    • v.34 no.2
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    • pp.63-68
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    • 2013
  • Activeness of exercise is critical for stroke rehabilitation so that application of stimulation in response to patient's intention would be effective in FES cycling. The purpose of this study was to investigate the relationship between muscle reaction force (MRF) and electromyogram (EMG) during cycling exercise, for the future usage of MRF as patients' intention signal. Seven young men ($24{\pm}1.63$ yrs) participated in this study. Cycling speed was set to 20 RPM and 60 RPM. MRF and EMG were measured in the vastus lateralis muscle of right leg. Active cycling was performed at the maximal load (16 Nm) of an ergometer. Angle dependent artifact in MRF was measured from passive cycling and was subtracted from the MRF of active cycling. The delay of MRF with respect to EMG envelope and their correlation coefficients were derived from the best of cross correlation. MRF was significantly correlated with EMG amplitude in all subjects (p<0.01). Their mean correlations were 0.84 and 0.91 for 20 RPM and 60 RPM, respectively. Mean delay in MRF was 59.14 ms and 53.14 ms for 20 RPM and 60 RPM, respectively. The result suggests that MRF can be used to assess patient's intention for exercise as a substitute to EMG. The method may be applied to FES cycling to encourage patient's effort which is critical for stroke rehabilitation.

Effects of Dopamine on the Contractility and Action Potential of the Rabbit Papillary Muscle (Dopamine이 토끼 유두근의 수축력과 활동전압에 미치는 영향)

  • Huh, In-Hoi;Park, Jong-Wan
    • YAKHAK HOEJI
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    • v.32 no.6
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    • pp.402-414
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    • 1988
  • In order to clarify the receptor types and mechanisms underlying the positive inotropic effect of dopamine on the mammalian ventricular myocardium, the action potential, its first derivatives and isometric contraction of the rabbit papillary muscle were recorded using a force transducer and glass capillary microelectrodes filled with 3M KCl. The results were as follows; (1) In normal Tyrode solution, the contractile force was increased and duration of action potential was shortened with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (2) The dose-response curve was markedly shifted to the right by pretreatment with reserpine (5mg/kg i.p., 24hrs prior to the experiment). (3) In 19mM $K^+-Tyrode$ solution, the duration of action potential, maximum rate of rise (V_{max}) of action potential and overshoot were significantly increased with increments of dopamine concentration ($10^{-6}-10^{-4}M$). (4) The inotropic effect of dopamine on the rabbit papillary muscle pretreated with reserpine was antagonized by atenolol ($10^{-6}M$), but not by phentolamine ($3{\times}10^{-6}M$). (5) In rabbit papillary muscle partially depolarized by 19mM $K^+-Tyrode$ solution, slow electrical response (calcium mediated action potential) as well as contraction were restored by dopamine ($10^{-4}M$); this restoration was blocked by calcium antagonists ($3{\times}10^{-5}M$ $LaCl_3{\cdot}6H_2O$, $3{\times}10^{-6}M$ diltiazem) or ${\beta}-adrenoceptor$ antagonist ($3{\times}10^{-6}M$ atenolol), but not affected by ${\alpha}-adrenoceptor$ antagonist ($10^{-5}M$ phentolamine, $3{\times}10^{-6}M$ yohimbine) or vascular dopaminergic receptor antagonist ($10^{-5}M$ haloperidol). The above results may be interpreted as that the positive inotropic effect of dopamine through both direct and indirect action are caused by increase in slow inward current ($Ca^{2+}$ influx into themyocardial cell), and the direct action is mainly due to the stimulation of ${\beta}-adrenoceptors$ in the rabbit papillary muscle.

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Effect of Seizure on Prognosis in Acute Endosulfan Intoxication (급성 endosulfan 중독환자에서 경련이 예후에 미치는 영향)

  • Han, Byung-Gon;Lee, Jun-Ho;Lee, Kyung-Woo
    • Journal of The Korean Society of Clinical Toxicology
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    • v.7 no.2
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    • pp.77-82
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    • 2009
  • Purpose: In highly doses, endosulfan lowers the seizure threshold and elicits central nervous system stimulation, which can result in seizures, respiratory failure, and death. Management of seizure control is essential for survival and prognosis of intoxicated patients. This study assessed whether seizure time was an independent predictor mortality in patients with endosulfan poisoning. Methods: This retrospective study enrolled patients with endosulfan poisoning presenting to Masan Samsung Hospital and Gyeongsang National University Hospital from January 2003 to December 2008. The data were collected from clinical records and laboratory files. Using a multivariate logistic analysis, data on the total population was retrospectively analyzed for association with mortality. Results: Of the 24 patients with endosulfan poisoning, nineteen (79.1%) experienced seizure. The patients in the seizure group showed significantly lower Glasgow coma scale score, base excess, bicarbonate, and significant existence of mechanical ventilation, as compared to the non seizure group (n=5). Seizure, Glasgow coma scale score, systolic blood pressure, bicarbonate level, need for respiratory support, pulse rate, respiratory rate, pH, base excess, and seizure time were associated with mortality. The fatality rate of endosulfan poisoning was 54.1% with higher mortality among patients experiencing. Longer seizure time was associated with higher mortality. Conclusion: Seizure time can be a significant independent predictor of mortality in patients with acute endosulfan poisoning. Physicians should aggressively treat for seizure control in patients with acute endosulfan poisoning.

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A Study on the Hypotensive Action of Methanol Extract of Plantaginis Seed in the Rabbit (차전자 메탄올 엑기스의 혈압강하작용에 관한 연구)

  • 고석태;임동윤
    • YAKHAK HOEJI
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    • v.22 no.3
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    • pp.163-174
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    • 1978
  • Plantaginis seed has been applied in Chinese medicine a as well as in folk remedy. It was advocated that Plantaginis S Semeη exerts good therapeutic effects as anti-inflammatory, antitussive, obstipant and diuretic agent in some cases of alimentary, respiratory a and renal disorders. This study was carried out in order to r re-evaluate the pharmacological action, especially the hypotensive a action of Plantaginis Semen and to elucidate the mechanism of its a action, making use of Plantaginis Semen methanol extract (PME), because its basic pharmacological action, i. e., hypotensive action is n not clear. 1) PME, when administered into intravenous route, elicited the h hypotensive response dependent on the dose of PME given to the rabbit anesthetized with urethane. 2) This hypotensive response of P PME was inhibited by atropine and potentiated by physostigmine, but not influ$\varepsilon$need by vagotomization. 3) Depressor effect of PME was blocked by chlorisondamine, phentolamine, and bethanicline, while not altered by cyproheptadine, diphenhydramine and propran¬olol. 4) The secondary pressor response after blocking the depressor e effect of PME by chlorisondamine was produced, but this pressor response was deminished by atropine. 5) PME augmented the pressor e effect of norepinephrine and angiotensin, on the other hand, reduced b blood pressure elevated by carotid occlusion reflex. 6) These observa¬t tions suggest that PME may induce the hypotensive response via dual mechanisms of parasympathomimetic and sympatholytic action, that the positions of this action are cholinergic peripheral site and sympathetic ganglia respectively, and that PME may possess the pressor activity caused by stimulation of "atropine-sensitive site" which seems to existsin the sympathetic ganglia.

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