• Title/Summary/Keyword: CA model

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APPLICATION OF FUZZY LOGIC IN THE CLASSICAL CELLULAR AUTOMATA MODEL

  • Chang, Chun-Ling;Zhang, Yun-Jie;Dong, Yun-Ying
    • Journal of applied mathematics & informatics
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    • v.20 no.1_2
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    • pp.433-443
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    • 2006
  • In [1], they build two populations' cellular automata model with predation based on the Penna model. In this paper, uncertain aspects and problems of imprecise and vague data are considered in this model. A fuzzy cellular automata model containing movable wolves and sheep has been built. The results show that the fuzzy cellular automata can simulate the classical CA model and can deal with imprecise and vague data.

The Effect of Corporate Association on the Perceived Risk of the Product (소비자의 제품 지각 위험에 대한 기업연상과 효과: 지식과 관여의 조절적 역활을 중심으로)

  • Cho, Hyun-Chul;Kang, Suk-Hou;Kim, Jin-Yong
    • Journal of Global Scholars of Marketing Science
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    • v.18 no.4
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    • pp.1-32
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    • 2008
  • Brown and Dacin (1997) have investigated the relationship between corporate associations and product evaluations. Their study focused on the effects of associations with a company's corporate ability (CA) and its corporate social responsibility (CSR) on consumers' product evaluations. Their study has found that both of CA and CSR influenced product evaluation but CA association has a stronger effect than CSR associations. Brown and Dacin (1997) have, however, claimed that there are few researches on how corporate association impacts product responses. Accordingly, some of researchers have found the variables to moderate or to mediate the relationship between the corporate association and the product responses. In particular, there has been existed a few of studies that tested the influence of the reputation on the product-relevant perceived risk, but the effects of two types of the corporate association on the product-relevant perceived risk were not identified so far. The primary goal of this article is to identify and empirically examine some variables to moderate the effects of CA association and CSR association on the perceived risk of the product. In this articles, we take the concept of the corporate associations that Brown and Dacin (1997) had proposed. CA association is those association related to the company's expertise in producing and delivering its outputs and CSR association reflected the organization's status and activities with respect to its perceived societal obligations. Also, this study defines the risk, which is the uncertainty or loss of the product and corporate that consumers have taken in a particular purchase decision or after having purchased. The risk is classified into product-relevant performance risk and financial risk. Performance risk is the possibility or the consequence of a product not functioning at some expected level and financial risk is the monetary loss one perceives to be incurring if a product does not function at some expected level. In relation to consumer's knowledge, expert consumers have much of the experiences or knowledge of the product in consumer position and novice consumers does not. The model tested in this article are shown in Figure 1. The model indicates that both of CA association and CSR association influence on performance risk and financial risk. In addition, the effects of CA and CSR are moderated by product category knowledge (product knowledge) and product category involvement (product involvement). In this study, the relationships between the corporate association and product-relevant perceived risk are hypothesized as the following form. For example, Hypothesis 1a($H_{1a}$) is represented that CA association has a positive influence on the performance risk of consumer. Also, the hypotheses that identified some variables to moderate the effects of two types of corporate association on the perceived risk of the product are laid down. One of the hypotheses of the interaction effect is Hypothesis 3a($H_{3a}$), it is described that consumer's knowledges of the product moderates the negative relationship between CA association and product-relevant performance risk. A field experiment was conducted in order to examine our model. The company tested was not real but imagined to meet the internal validity. Water purifiers were used for our study. Four scenarios have been developed and described as the imaginary company: Type A with both of superior CA and CSR, Type B with superior CSR and inferior CA, Type C with superior CA and inferior CSR, and Type D with both inferior of CA and CSR. The respondents of this study were classified into four groups. One type of four scenarios (Type A, B, C, or D) in its questionnaire was given to the respondent who filled out questions. Data were collected by means of a self-administered questionnaire to the respondents, chosen in convenience. A total of 300 respondents filled out the questionnaire but 207 were used for further analysis. Table 1 indicates that the scales in this study are reliable because the range of coefficients of Cronbach's $\alpha$ are from 0.85 to 0.92. The composite reliability is in the range of 0,85 to 0,92 and average variance extracted is in 0.72-0.98 range that is higher than the base level of 0.6. As shown in Table 2, the values for CFI, NNFI, root-mean-square error approximation (RMSEA), and standardized root-mean-square residual (SRMR) are acceptably close to the standards suggested by Hu and Bentler (1999):.95 for CFI and NNFI,.06 for RMSEA, and.08 for SRMR. We also tested discriminant validity provided by Fornell and Larcker (1981). As shown in Table 2, we found strong evidence for discriminant validity between each possible pair of latent constructs in all samples. Given that these batteries of overall goodness-of-fit indices were accurate and that the model was developed on theoretical bases, and given the high level of consistency across samples, this enables us to proceed the previously defined scales. We used the moderated hierarchical regression analysis to test the influence of the corporate association(CA and CSR associations) on product-relevant perceived risk(performance and financial risks) and to identify the variables moderating the relationship between the corporate association and product-relevant performance risk. In this study, dependent variables are performance and financial risk. CA and CSR associations are described the independent variables. The moderating variables are product category knowledge and product category involvement. The results are, as expected, found that CA association has statistically a significant influence on the perceived risk of the product, but CSR association does not. Product category knowledge and involvement moderate the relationship between the CA association and the perceived risk of the product. However, the effect of CSR association on the perceived risk of the product is not moderated by the consumers' knowledge and involvement. For this result, it is necessary for a corporate to inform its customers CA association more than CSR association so that they could be felt to be the reduction of the perceived risk. The important theoretical contribution of this research is the meanings that two types of corporate association that Brown and Dacin(1997), and Brown(1998) have proposed replicated the difference of the effects on product evaluation. According to Hunter(2001), it was an important affair to accomplish the validity of a particular study and we had to take about ten studies to deduce a strict study. Next, there is the contribution of the this study to find that the effects of corporate association on the perceived risk of the product are varied by the moderator variables. In particular, the moderating effect of knowledge on the relationship between corporate association and product-relevant perceived risk has not been tested in Korea. In the managerial implications of this research, we suggest the necessity to stress the ability that corporate manufactures the product well(CA association) than the accomplishment of corporate's social obligation(CSR association). This study suffers from various limitations that imply future research directions. The moderating effects of product category knowledge and involvement on the relationship between corporate association and perceived risk need to be replicated. Next, future research could explore whether the mediated effects of the perceived risk has the relationship between corporate association and consumer's product purchase. In addition, to ensure the external validity of the study will be needed to use realistic company, not artificial.

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Effect of Dietary Protein Level on Renal Function and Bone Metabolism in Rats with Reduced Renal Mass When Dietary P Level is Equal (만성신부전 모델쥐에서 인의 함량은 같고 단백질 수준이 다른 식이가 신기능과 골격 대사에 미치는 영향)

  • 이현숙;김화영
    • Journal of Nutrition and Health
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    • v.34 no.4
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    • pp.359-366
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    • 2001
  • Studies were carried out to explore the influence of dietary protein level on bone metabolism in uninephrectomized rat (experimental renal failure model) when dietary Ca and P contents were equal. Male rats were uninephrectomized or sham operated and fed 8%, 15% and 40% casein diets for 24 weeks. Ca and P contents of the all diet were 0.4% and 0.6% respectively. The results are summarized as follows. We did not found any significant difference in PTH and Ca level of the serum, Ca intake and Ca excretion among the experimental groups. There was significant positive correlation between the PTH and phosphate level. There was significant inverse correlation between serum Ca and creatinine level. The effect of the dietary protein level and renal mass loss on density and Ca contents of the bone were small and different according to the kinds of the bone. Low protein diet was associated with a significant enhancement of scapular density. Femur and vertebra density, however, were not influenced by dietary protein level and uninephrectomy. Light microscopic examination showed several calcified foci in the kidney in all experimental groups. Low protein diets have been used for a long time in the conservative management of chronic renal failure as they have a beneficial effect in preventing the appearance of symptoms. This study elucidated that part of beneficial effects of the low protein diet related to the suppression of the hyperphosphatemia. And these results, even though uninephrectomized rats fed high protein diet, the secondary hyperparathyroidism is supressed by the regulation of the P level. Therefore this study emphasized the need to pay more attention to the regulation of dietary P level as well as dietary protein content in chronic renal failure. (Korean J Nutrition 34(4): 359∼366, 2001)

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Effects of Calcium and Genistein on Body Fat and Lipid Metabolism in High Fat-induced Obese Mice (칼슘과 제니스테인 섭취가 고지방식이로 유도된 비만 모델 마우스의 체지방과 지질대사에 미치는 영향)

  • Kim, Mi-Hyun;Kim, Seol-Hee;Park, Hyun-Woo;Kim, Wan-Gi;Lee, Yeon-Sook
    • Journal of Nutrition and Health
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    • v.39 no.8
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    • pp.733-741
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    • 2006
  • The study was conducted to investigate the effects of dietary calcium and soy isoflavone on body fat and lipid metabolism in high fat-induced obesity. Four week old female C57/BL6J mice, known as a good model of diet-induced obesity, were fed low Ca and high fat diet for 6 weeks. After induced obesity, mice were divided into six groups according to diets varying calcium contents (0.1 or 1.5%) and genistein contents (0 or 500 or 1,000 ppm). Body weight, fat pad (perirenal fat and parameterial fat), adipocyte size, serum total lipid and total cholesterol were significantly decreased by both high Ca intake and genistein supplementation. However, the effect of genistein supplementation showed in low Ca-fed groups. Serum LDL-cholesterol and TG were significantly decreased by high Ca intake and genistein supplementation, respectively. In liver, lipogenic enzymes (fatty acid synthase and malic enzyme) activity and TG were significantly decreased by both high Ca intake and genistein supplementation. This inhibitory effect of genistein on lipogenic enzymes showed in low Ca-fed groups. But liver total cholesterol and total lipid were significantly decreased by high Ca intake and genistein supplementation, respectively. Fecal excretion of total lipid, total cholesterol and TG were significantly increased by high Ca intake, not by genistein supplementation. In conclusion, high calcium intake and genistein supplement may be beneficial for suppression of obesity through direct anti-adipogenesis by decreasing fat weight and size and indirect anti-lipo-genesis by inhibiting lipogenic enzymes activity and improving lipid profile.

Green Tea Extract (CUMS6335) Inhibits Catecholamine Release in the Perfused Adrenal Medulla of Spontaneously Hypertensive Rats

  • Lim, Dong-Yoon
    • Natural Product Sciences
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    • v.13 no.1
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    • pp.68-77
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    • 2007
  • The aim of the present study was to examine the effects of green tea extract (CUMS6335) on the release of CA evoked by cholinergic stimulation and direct membrane-depolarization in the perfused model of the adrenal gland isolated from the spontaneously hypertensive rats (SHRs), and to establish the mechanism of action. Furthermore, it was also to test whether there is species difference between animals, and between CUMS6335 and EGCG, one of biologically the most powerful catechin compounds found in green tea. CUMS6335 $(100\;{\mu}g/ml)$, when perfused into an adrenal vein for 60 min, time-dependently inhibited the CA secretory responses evoked by ACh (5.32mM), high $K^+$(56 mM), DMPP $(100\;{\mu}M)$, and McN-A-343 $(100\;{\mu}M)$ from the isolated perfused adrenal glands of SHRs. However, CUMS6335 itself did fail to affect basal catecholamine output. Also, in adrenal glands loaded with CUMS6335 $(100\;{\mu}g/ml)$, the CA secretory responses evoked by Bay-K-8644 $(10\;{\mu}M)$ and cyclopiazonic acid $(10\;{\mu}M)$ were also inhibited in a relatively time-dependent fashion. However, in the Presence of EGCG $(8.0\;{\mu}g/ml)$ for 60 min, the CA secretory response evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were not affected except for last period. Collectively, these results indicate that CUMS6335 inhibits the CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by direct membrane-depolarization from the perfused adrenal gland of the SHR. It seems that this inhibitory effect of CUMS6335 is exerted by blocking both the calcium influx into the rat adrenal medullary chromaffin cells and the uptake of $Ca^{2+}$ into the cytoplasmic calcium store, which are at least partly relevant to the direct interaction with the nicotinic receptor itself. It seems likely that there is much difference in mode of the CA-releasing action between CUMS6335 and EGCG.

Structure-Antifungel Activity Relationships of Cecropin A Hybrid Peptides against Trichoderma sp.

  • Shin, Song-Yub;Lee, Dong-Gun;Lee, Sung-Gu;Kim, Kil-Lyong;Lee, Myung-Kyu;Hahm, Kyung-Soo
    • Journal of Microbiology
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    • v.35 no.1
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    • pp.21-24
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    • 1997
  • The hybrid peptides, CA-ME, CA-MA and CA-BO, with the N-terminal sequence 1-8 of cecropin A and the N-terminal sequences 1-12 of melittin, magainin 2 and bombinin, respectively, have more improved antibacterial activities. CA-MA was found to have stronger antifungal activity against Trichoderma sp than other hybrid peptides and their parental peptides. In order to elucidate the relationships between the peptide structure and antifungal activity, several analogues of CA-MA or CA-BO were also designed and synthesized by the solid phase method. An tifungal activity was measured against T. reesei and T. viride, and hemolytic activity was measured by a solution method against human red blood cells. The residue 16 of CA-MA, Ser, was found to be important for antifungal activity. When the residue was substituted with Leu, showed powerful antifungal activity was dramatically decreased. CA-MA, P1, P4 and P5 designed in this study showed powerful antifungal activity against T. reesei and T. viride with low hemolytic activity against human red blood cells. These hybrid peptides will be potentially useful model to further design peptides with powerful antifungal activity for the effective therepy of fungal infection and understand the mechanisms of antifungal actions of hybrid peptides.

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Influence of Total Ginseng Saponin on Catecholamine Secretion Evoked by Nicotinic Receptor Stimulation in the Perfused Rat Adrenal Gland

  • Lim Dong-Yoon;Kil Young-Woo
    • Proceedings of the Ginseng society Conference
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    • 2002.10a
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    • pp.401-415
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    • 2002
  • Lim and his coworkers (1987; 1988; 1989) have also found that all of total Ginseng saponin, panaxadiol-and panaxatriol-type saponins cause the increased secretion of catecholamines (CA) in a $Ca^{2+}$ -dependent fashion from the isolated perfused rabbit adrenal glands through the activation of cholinergic (both nicotinic and muscarinic) receptors. These CA secretory effects are partly due to the direct action on the rabbit adrenomedullary chromaffin cells. However, the present study was designed to examine the effect of total ginseng saponin on CA secretion evoked by activation of cholinergic nicotinic receptors in the isolated perfused model of the rat adrenal gland. Total ginseng saponin given (100 ${\mu}g$/20 min) into an adrenal vein did fail to produce alteration of spontaneous CA release from the rat adrenal medulla. Acetylcholine(5.32 mM)- and DMPP(100 ${\mu}M$, a selective nicotinic receptor agonist)-evoked CA secretory responses were reduced markedly after the pretreatment with the total ginseng saponin at a rate of 100 ${\mu}g$/6.2 ml/20 min, respectively. Pretreatment with total ginseng saponin also depressed greatly high potassium (56 mM, a membrane depolarizing agent)- and Bay-K-8644 (10 ${\mu}M$, a calcium channel activator)-induced CA secretions. Taken together, it is thought that total ginseng saponin can inhibit the releasing effect of CA evoked by nicotinic receptor stimulation from the isolated perfused rat adrenal medulla, which seems to be associated to the direct inhibition of influx through L-type calcium channel into the rat adrenomedullary chromaffin cells. It seems that there is species differences in the adrenomedullary catecholamine secretion between the rabbit and rat.

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Probing Atomic Structure of Quarternary Aluminosilicate Glasses using Solid-state NMR (다성분계 현무암질 비정질 규산염의 원자 구조에 대한 고상핵자기 공명 분광분석연구)

  • Park, Sun-Young;Lee, Sung-Keun
    • Journal of the Mineralogical Society of Korea
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    • v.22 no.4
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    • pp.343-352
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    • 2009
  • High-resolution Solid-state NMR provides element specific and quantitative information and also resolves, otherwise overlapping atomic configurations in multi-component non-crystalline silicates. Here we report the preliminary results on the effect of composition on the structure of CMAS (CaO-MgO-$Al_2O_3-SiO_2$) silicate glasses, as a model system for basaltic magmas, using the high-resolution 1D and 2D solid-state NMR. The $^{27}Al$ MAS NMR spectra for the CMAS silicate glasses show that four-coordinated Al is predominant, demonstrating that $Al^{3+}$ is network forming cation. The peak position moves toward lower frequency about 4.7 ppm with increasing $X_{MgO}$ due to an increase in $Q^4$(4Si) fraction with increasing Si content, indicating that Al are surrounded only by bridging oxygen. $^{17}O$ MAS NMR spectra for $CaAl_2SiO_6$ and $CaMgSi_2O_6$ glasses qualitatively suggest that NBO fraction in the former is smaller than that in $CaMgSi_2O_6$ glasses. As $^{17}O$ 3QMAS NMR spectrum of model quaternary aluminosilicate glass resolved distinct bridging and non-bridging oxygen environments, atomic structure for natural magmas can also be potentially probed using high-resolution 3QMAS NMR.

Effect of Aspartic Acid and Lysine on Polymorphism of Calcium Carbonate Crystal Formed by Gas-Liquid Reaction (기액반응에서 형성된 탄산칼슘 결정의 다형성에 미치는 Aspartic acid와 Lysine의 영향)

  • Song, Seong-Moon;Seong, Back-In;Koo, Ji-Hoi;Kim, In-Ho
    • Korean Chemical Engineering Research
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    • v.49 no.1
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    • pp.109-113
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    • 2011
  • Crystallization of calcium carbonate were performed by adding aspartic acid and lysine into $CaCl_2$ solution for understanding biomineralization in gas-liquid reaction of $NH_4HCO_3$ and $CaCl_2$. Proportion between calcite and vaterite of calcium carbonate crystals was identified by changing conditions such as reaction time, addition amount of aspartic acid, lysine, $CaCl_2$, and $NH_4HCO_3$. FT-IR(Fourier Transform Infrared spectroscopy) instrument was used to perform analysis of vaterite ratio. Under the condition of $NH_4HCO_3$ 10 g and no additive, an increase of vaterite crystal changed to a decrease around 0.15 M $CaCl_2$. Then it largely increased at 0.25 M $CaCl_2$, after vaterite proportion was rising again at 0.20 M $CaCl_2$. In contrast to that, vaterite crystal continuously decreased to 0.2 M $CaCl_2$, and increased from 0.25 M $CaCl_2$ with 20 g $NH_4HCO_3$. Vaterite crystals were observed to be a maximum after 2days with lysine addition, but $CaCO_3$ vaterite crystals showed minimum with aspartic acid.

Inhibitory Effects of Total Ginseng Saponin on Catecholamine Secretion from the Perfused Adrenal Medulla of SHRs

  • Jang, Seok-Jeong;Lim, Hyo-Jeong;Lim, Dong-Yoon
    • Journal of Ginseng Research
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    • v.35 no.2
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    • pp.176-190
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    • 2011
  • There seems to be some controversy about the effect of total ginseng saponin (TGS) on the secretion of catecholamines (CA) from the adrenal gland. Therefore, the present study aimed to determine whether TGS can affect the CA release in the perfused model of the adrenal medulla isolated from spontaneously hypertensive rats (SHRs). TGS (15-150 ${\mu}g/mL$), perfused into an adrenal vein for 90 min, inhibited the CA secretory responses evoked by acetylcholine (ACh, 5.32 mM) and high $K^+$ (56 mM, a direct membrane depolarizer) in a dose- and time-dependent fashion. TGS (50 ${\mu}g/mL$) also time-dependently inhibited the CA secretion evoked by 1.1-dimethyl-4 -phenyl piperazinium iodide (DMPP; 100 ${\mu}M$, a selective neuronal nicotinic receptor agonist) and McN-A-343 (100 ${\mu}M$, a selective muscarinic M1 receptor agonist). TGS itself did not affect basal CA secretion (data not shown). Also, in the presence of TGS (50 ${\mu}g/mL$), the secretory responses of CA evoked by veratridine (a selective $Na^+$ channel activator (50 ${\mu}M$), Bay-K-8644 (an L-type dihydropyridine $Ca^{2+}$ channel activator, 10 ${\mu}M$), and cyclopiazonic acid (a cytoplasmic $Ca^{2+}$-ATPase inhibitor, 10 ${\mu}M$) were significantly reduced, respectively. Interestingly, in the simultaneous presence of TGS (50 ${\mu}g/mL$) and N${\omega}$-nitro-L-arginine methyl ester hydrochloride [an inhibitor of nitric oxide (NO) synthase, 30 ${\mu}M$], the inhibitory responses of TGS on the CA secretion evoked by ACh, high $K^+$, DMPP, McN-A-343, Bay-K-8644, cyclopiazonic acid, and veratridine were considerably recovered to the extent of the corresponding control secretion compared with the inhibitory effect of TGS-treatment alone. Practically, the level of NO released from adrenal medulla after the treatment of TGS (150 ${\mu}g/mL$) was greatly elevated compared to the corresponding basal released level. Taken together, these results demonstrate that TGS inhibits the CA secretory responses evoked by stimulation of cholinergic (both muscarinic and nicotinic) receptors as well as by direct membrane-depolarization from the isolated perfused adrenal medulla of the SHRs. It seems that this inhibitory effect of TGS is mediated by inhibiting both the influx of $Ca^{2+}$ and Na+ into the adrenomedullary chromaffin cells and also by suppressing the release of $Ca^{2+}$ from the cytoplasmic calcium store, at least partly through the increased NO production due to the activation of nitric oxide synthase, which is relevant to neuronal nicotinic receptor blockade, without the enhancement effect on the CA release. Based on these effects, it is also thought that there are some species differences in the adrenomedullary CA secretion between the rabbit and SHR.