• 대한수의학회지
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• 제43권3호
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• pp.373-382
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• 2003

Magnesium ion ($Mg^{2+}$) is a vasodilator, but little is known about its mechanism of action on vascular system. In vitro, extracellular magnesium sulfate ($MgSO_4$) produced relaxation in phenylephrine (PE) or high KCl-precontracted isolated rat thorocic aorta with (+E) or without (-E) endothelium in a concentration-dependent manner. The $MgSO_4$-induced relaxations were not affected by removal of the endothelium. Pretreatment of +E or -E aortic rings with nitric oxide synthase (NOS) inhibitors ($20{\mu}M$ L-NNA, $100{\mu}M$ L-NAME, $1{\mu}M$ dexamethasone and $400{\mu}M$ aminoguanidine), cyclooxygenase inhibitor ($10{\mu}M$ indomethacin), guanylate cyclase inhibitors ($10{\mu}M$ ODQ and $30{\mu}M$ methylene blue) and $Ca^{2+}$ transport blocker ($10{\mu}M$ ryanodine) did not affect the relaxant effects of $MgSO_4$. $Ca^{2+}$ channel blockers ($0.3{\mu}M$ nifedipine and $0.5{\mu}M$ veropamil) completely decreased the relaxant effects of $MgSO_4$ in +E and -E aortic rings. However, in $Ca^{2+}$-free medium, $MgSO_4$-induced vasorelaxation was potentiated and this response was inhibited by nifedipine. Protein kinase C (PKC) inhibitors ($1.0{\mu}M$ staurosporine, $0.5{\mu}M$ tamoxifen and $0.1{\mu}M$ H7) or PLC inhibitor ($100{\mu}M$ NCDC) markedly decreased the relaxant effects of $MgSO_4$ in +E and -E aortic rings. In vivo, infusion of $MgSO_4$ elicited significant decreases in arterial blood pressure. After intravenous injection of nifedipine ($150{\mu}g/kg$) and NCDC (3 mg/kg), infusion of $MgSO_4$ inhibited the $MgSO_4$-lowered blood pressure markedly. However, after introvenous injection of saponin (15 mg/kg), L-NNA (3 mg/kg), L-NAME (5 mg/kg), indomethacin (2 mg/kg), methylene blue (15 mg/kg) and aminoguanidine (10 mg/kg) failed to inhibit it. These results suggest that endothelial NQ-cGMP or prostaglandin pathway is not involved in vasorelaxant or hypotensive action of $Mg^{2+}$ and that these effects are due to the inhibitory action of $Mg^{2+}$ on the $Ca^{2+}$ channel or PLC-PKC pathway, and are due to the competitive influx of $Mg^{2+}$ and $Ca^{2+}$ through the $Ca^{2+}$ channel.

• 대한약리학회지
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• 제18권1호
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• pp.1-10
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• 1982

중추의 ${\beta}-adrenoceptor$가 신장기능의 조절에 있어서 어떠한 역할을 하고 있는지를 알고자, 가토의 측뇌실내에 isoproterenol 및 propranolol을 투여하여 신장기능의 변동을 관찰하였다. Isoproterenol은 $5{\sim}50{\mu}g/kg$ i.c.v.의 범위에서 항이뇨작용을 나타냈으나 이는 주로 전신혈압하강에 따르는 신혈류 및 사구체여과율의 감소에 기인하며 세뇨관에서의 Na 재흡수억제효과는 음폐된 것으로 추론되었다. Propranolol $(500\;{\mu}g/kg\;i.c.v.)$은 신장기능에 현저한 변동을 초래하지 아니하였으나, propranolol후에 isoproterenol을 투여하면 전신혈압하강은 현저히 약화됨과 동시에, Na, K 배설의 증가와 신혈류의 증가, 그리고 뇨량증가경향이 관찰되었다. 즉, prapranolol에 의하여 isoproterenol의 강압작용은 영향을 받으나 신장작용은 영향받지 아니하고 현저하게 표현되었다. 본연구의 결과는, 중추의 ${\beta}-adrenoceptor$도 ${\alpha}-receptor$보다는 약하지만 신장기능의 조절에 있어서 어떤 역할을 하고 있음을 시사하였다.

• 대한약리학회지
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• 제12권2호
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• pp.33-41
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• 1976

Agkistrodon halys (Crotalidae) is the only species of poisonous snakes in Korea, and is divided into three subspecies; Agkistrodon bromhoffii brevicaudus, Agkistrodon calaginosus and Agkistrodon saxatilis. With the three venoms, the pharmacological actions on the cardiovascular system and intestine as well as some toxicological characteristics were studied. In addition, the precipitin test in an agar gel medium was employed for immunological comparison of the venoms and the sera of envenomed patients. The results obtained were as follows: Lyophilized venoms contained solids of $211{\sim}273mg/ml$, and LD50 to mice were 1.73 and 0.86 mg/kg in venoms of Agkistrodon bromhoffii brevicaudus obtained on July and October respectively, and 0.40 and 0.32 mg/kg in Agkistrodon calaginosus and the venoms of Agkistrodon saxatilis obtained on October was 2.29 mg/kg. Isoelectric focusing of lyophilized snake venoms showed 19 to 22 protein fractions and 2 to 3 isoamylase fractions. Acute irreversible hypotension was caused by the intravenous injection of large doses of venoms in rabbits and cats, but at the small doses, acute hypotension followed by slow recovery. Little changes of cardiac movements by the venom injection despite of marked hypotension were showed except bradycardia and arrhythmia prior the death. Also no changes on the isolated rabbit atria by the snake venoms were noted. The hypotensive effect of the snake venoms was prevented by the bilateral vagotomy or atropine pretreatment (1 mg/kg), but they did not affect when already the hypotension has undergone. In the isolated rabbit duodenum, small doses of venom increased the phasic movement, while large doses decreased after spastic contraction. With the injection of venoms in dog, strong contraction of gall-bladder was caused and it was not blocked by the pretreatment with phenoxybenzamine (10 mg/kg) or atropine (1.4 mg/kg). In the venoms of Agkistrodon bromhoffii brevicaudus and Agkistrodon calaginosus, at least 5 antigenic components were detected, and four of them were shared in common with each other. Polyvalent antivenin (Wyeth Lab. USA) had three common precipitating antibodies with the venom of Agkistrodon bromhoffii brevicaudus and Akistrodon calaginosus. In the serum of envenomed patients, no precipitating antibodies were seen to the venoms and little changes in serum protein, GOT and GPT were observed. In conclusion, the snake venoms obtained in Korea were highly toxic and caused chiefly the vascular collapse leading to death. This vascular collapse was resulted largely by cholinergic effects, and not cardiotoxin of venoms. In human, it is likely that precipitating antibodies to venom were not produced by an envenomed incidence to poisonous snakes.

• 대한약리학회지
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• 제28권1호
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• pp.27-40
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• 1992

Taurine은 유황 함유 아미노산으로서 뇌내에서 억제작용을 갖는 신경전달물질 역할을 하는것으로 알려져 있다. Taurine을 가토의 측뇌실내에 투여하여 혈압 및 심박에 미치는 영향을 검토하고 그 작용 기전을 규명코자 본 연구를 시행하여 얻은 연구결과는 다음과 같다. Taurine $(0.15{\sim}1.5\;mg)$은 urethane 마취 가토의 측뇌실내로 주사하였을때 혈압강하작용 및 심박감소작용이 현저하고 지속적인 용량반응 곡선을 나타내었다. 이와 동시에 상당한 호흡억제 작용도 관찰되었다. 그러나 동일량의 taurine을 정맥내에 투여시 혈압 및 심박에 아무런 영향을 미치지 못하였다. Taurine의 혈압 하강작용은 chlorisondamine, clonidine, strychnine, bicuculline등으로 전처치시 유의하게 억제되었으나 atropine, 양측 미주신경절단, propranolol 및 metoclopramide등의 전처치로 영향을 받지 않았다. 더우기 taurine은 norepinephrine의 승압 반응에도 영향을 미치지 못하였다. Taurine의 심박감소 작용은 chlorisondamine, propranolol, clonidine, strychnine 및 bicuculline등으로 전처리시 현저히 차단되었으나 atropine, 양측 미주신경절단, metoclopramide 등의 전처리로 영향을 받지 않았다. 이상의 연구한 결과로 보아, taurine은 가토의 측뇌실내 투여시 지속적이며 현저한 혈압하강 및 심박감소를 일으키며 이러한 작용은 뇌내의 catecholamine 뉴론과 관련있는 taurine (glycine) 및 gamma-aminobutyric acid (GABA) 수용체를 통해서 나타나는 것으로 사료된다.

• 대한약리학회지
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• 제26권1호
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• pp.7-12
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• 1990

흰쥐로 부터 심장을 적출하여 Langendorff 관류장치에 현수하여 Krebs-Hensleit 영양액으로 분당 12ml속도로 30분간 관류시킨 후 관류 속도를 분당 1ml로 줄여(ischemia)60분간 관류시키면, 적출심장의 수축력이 현저히 감소되었고, resting tension이 현저히 증가되었다. 또 적출심장으로부터 유출되는 관류액의 250nm에서의 UV흡광치는 증가되었으며, 좌심실내의 칼슘의 농도는 대조군보다 상당히 증가되었다. 본 실험에서는 흰쥐에서 항염증작용, 혈압강하 및 서맥 작용, 평활근 및 심장근에서 근이완작용을 나타내는 cyclobuxine D의 ischemia에 의해 유도된 심장손상에 대한 보호효과를 관찰하였다. Cyclobuxine D(100ng/ml)는 ischemia에 의해 유발된 적출심장의 수축력 감소와 resting tension의 증가를 유의하게 억제하였으며, 심장으로부터의 ATP metabolites의 유출과 좌심실내의 칼슘 축적을 억제시켰다. 이상의 결과는 Cyclobuxine D가 ischemia에 의해 유발된 손상으로 부터 심장을 보호할 수 있음을 나타내며, 이는 cyclobuxine D의 심장세포내의 칼슘 유입 억제작용에 기인하는 것으로 사려된다.

• 성인간호학회지
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• 제12권1호
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• pp.88-98
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• 2000

Hemodialysis(HD)-associated hypotension is a frequent complication, but it is difficult to manage. Until now, several maneuvers have been tried to prevent the HD-associated hypotension. Of these, the sodium content of dialysate was regarded as an important factor for maintaining blood pressure during HD. In this study, we evaluated the effect of hypertonic dialysate on blood pressure, interdialytic weight gain and the incidence of thirst. The study was done for 6 weeks successively with 3 different groups. Each patient was dialysed with 3 different dialysates for 2 weeks: Group I(Conventional HD: sodium concentration: 137 mEq/L), Group II(Hypertonic HD: 147 mEq/L) and Group III (Sequential HD: from 147 to 140 mEq/L). Hemodynamic parameters(blood pressure, pulse rate and ultrafiltration rate), biochemical parameters(hematocrits, blood urea nitrogen, creatinine, osmolality, sodium, potassium, chloride, fasting blood sugar) and complications (interdialytic weight gain & thirsty sensation) were compared among 3 groups. The results were as follows: 1. Decline of systolic blood pressure and diastolic blood pressure at the time of a 3 hour check during hemodialysis was lower in the Group II than Group I and III (p=0.002; p=0.012). and decline of diastolic blood pressure at the time of a 4 hour check during hemodialysis was lower in the Group II and III than Group I (p=0.04). 2. Incidence of hypotensive episodes during dialysis was significantly lower in Group II than group I (p=0.0287). 3. The ultrafiltration in Group III at the time of 1 hour, 2 hour and 3 hour check during hemodialysis was higher than that in Group I and II at the time of 1 hour, 2 hour and 3 hour check during hemodialysis respectively (p=0.0001; p=0.0001; p=0.0004). 4. Interdialytic weight gain was higher in Group I($3.1{\pm}0.8$) than Group I($2.8{\pm}0.8$) and III ($2.9{\pm}0.9$) (p=0.0422). 5. Hematologic and biochemical results were not significantly different among 3 Groups. 6. Frequency of thirst was different in Group I, II and III, $0.05{\pm}0.12$, $0.41{\pm}0.24$and $0.22{\pm}0.29$ respectively (p=0.0259). The results suggest that hypertonic HD was effective in preventing HD-associated hypotension but interdialytic weight gain and thirst sensations were increased as compared with a conventional method. In this situation, sequential HD seems to be an alternative method to minimizes the side effect of hypertonic HD.

• The Korean Journal of Physiology and Pharmacology
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• 제15권6호
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• pp.339-344
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• 2011

Ulmus davidiana var. japonica Rehder (Urticales: Ulmaceae) (UD) is a tree widespread in northeast Asia. It is traditionally used for anticancer and anti-inflammatory therapy. The present study investigated the effect of an ethanol extract of UD on vascular tension and its underlying mechanism in rats. The dried root bark of UD was ground and extracted with 80% ethanol. The prepared UD extract was used in further analysis. The effect of UD on the cell viability, vasoreactivity and hemodynamics were investigated using propidium iodide staining in cultured cells, isometric tension recording and blood pressure analysis, respectively. Low dose of UD ($10{\sim}100{\mu}g/ml)$ did not affect endothelial cell viability, but high dose of UD reduced cell viability. UD induced vasorelaxation in the range of $0.1{\sim}10{\mu}g/ml$ with an $ED_{50}$ value of $2{\mu}g/ml$. UD-induced vasorelaxation was completely abolished by removal of the endothelium or by pre-treatment with L-NAME, an inhibitor of nitric oxide synthase. UD inhibited calcium influx induced by phenylephrine and high $K^+$ and also completely abolished the effect of L-NAME. Intravenous injection of UD extracts (10~100 mg/kg) decreased arterial and ventricular pressure in a dose-dependent manner. Moreover, UD extracts reduced the ventricular contractility (+dP/dt) in anesthetized rats. However, UD-induced hypotensive actions were minimized in L-NAME-treated rats. Taken together, out results showed that UD induced vasorelaxation and has antihypertensive properties, which may be due the activation of nitric oxide synthase in endothelium.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.95-95
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• 2001

Ciinidipine (FRC-8635) is a newly synthesized novel DHP type of organic Ca$\_$2＋/channel blockers that have been developed so far in Japan (Yoshimoto et al., 1991 : Hosono et at., 1992). It also has a blocking action on L-type voltage-dependent Ca$\^$2＋/channel (VDCCs) in the rabbit basilar artery (Oike et al., 1990) and a slow-onset and long-lasting hypotensive action in clinical and experimental studies (Ikeda et al., 1992 ; Tominaga et al., 1997). Recent electrophysiological data indicate that cilnidipine might be a dual-channel antagonist for peripheral neuronal N-type and vascular L-type Ca$\^$2＋/channels (Oike et al., 1990 ; Fujii et al., 1997; Uneyama et at., 1997). However, little is known about the involvement of N-type VDCCs in contributing to the muscarinic receptor-mediated CA secretion. Therefore, the present study was attempted to investigate the effect of cilinidipine on secretion of catecholamines (CA) evoked by ACh, high K$\^$＋/, DMPP and McN-A-343 from the isolated perfused rat adrenal gland. Cilnidipine (1-10 ${\mu}$M) perfused into an adrenal vein for 60 min produced dose- and time-dependent inhibition in CA secretory responses evoked by ACh (5.32${\times}$10$\^$-3/M), DMPP (10$\^$-4/ M for 2 min) and McN-A-343 (10$\^$-4/ M for 2 min). However, lower dose of lobeline did not affect CA secretion by high K$\^$＋/(5.6${\times}$10$\^$-2/ M), higher dose of it reduced greatly CA secretion of high K$\^$＋/. Cilnidipine itself did also fail to affect basal catecholamine output. Furthermore, in adrenal glands loaded with cilnidipine (10 ${\mu}$M), CA secretory response evoked by Bay-K-8644 (10 ${\mu}$M), an activator of L-type Ca$\^$2＋/channels was markedly inhibited while CA secretion by cyclopiazonic acid (10 ${\mu}$M), an inhibitor of cytoplasmic Ca$\^$2＋/-ATPase was no affected. Moreover, $\omega$-conotoxin GVIA (1 ${\mu}$M), given into the adrenal gland for 60 min, also inhibited time-dependently CA secretory responses evoked by ACh and high K$\^$＋/.

• 대한간호학회지
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• 제30권3호
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• pp.549-559
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• 2000

The purpose of this study was to investigate the correlation between the knowledge and educational needs related to recurrent in coronary artery bypass graft patients as a basis to provide an individual nursing education for the population. The subjects consisted of 110 patients who had coronary artery bypass graft(CABG) at Asan Medical Center in Seoul and Sechong hospital in Buchon. Data was obtained from a knowledge questionnaire and a learning needs questionnaire between November 1998 and February 1999. Data were analyzed using SAS program for Wilcoxon rank sum test and Spearman correlation coefficient. The results were as follows : 1. With regard to the 18 items to measure knowledge, the mean (median) of items 'don't know' was 4.9(4) items. The mean (median) of items answered wrong was 3.2(3) items. The number of items answered 'don't know' tend to show higher in those who had less education, blue color jobs and myocardiac infarction history than in their counter parts. There were higher frequency of items answered 'don't know' in those who had no hypertension 2. With regard to the level of knowledge by questionnaire about CABG, The most "I dont know" (59.1%) highly response was 'He has to be treated with anticoagulant drug to prevent revasculized vessel from obstructing.' The seond highest response (56.4%) was 'If you were hypotensive, the coronary attack would collapse. 'During the hospitalized day, the patient has complete bedrest.' The highest error probability was cholesterol has not to intake.', 'After surgery, the sexual life is need controlled for 1 year. 3. The mean of educational needs was 3.38. With regard to the level of learning needs by sentence about CABG, 'Food that benefit heart disease', 'Recurrence possibility of heart disease', 'Management method of operation site', 'Risk symptom that visit hospital or report immediately' were higher than other sentenses. With regard to the level of learning needs by factor 'food(5 items)', 'disease(9 items)' and 'exercise(3 items)' showed the highest than other factors. The educational needs by patients characteristics tend to show higher in males, under the age of 49, middle or high school degree, previous experience of admission with coronary artery disease, history of myocardial infarction, expierience of PTCA, history of cerebro-vascular accident, previous expierience of smoking than in their counter parts. 4. The number of items answered 'don't know', wrong and correct weren't correlated with the level educational needs. As the results, the number of items answered 'don't know' tend to show higher in those who had less educated, blue color jobs and myocardiac infarction history than in their counter parts. There were higher frequency of items answered 'don't know' in those who had no hypertension .There were higher frequency of items answered 'don't know' on anti-thrombolitic theraphy, hypotension and pain relief. Also there were higher frequency of items answered wrong on bed rest period, cholesterol intake, and sexual life. Educational needs were higher in young age group, had previous experience of procesure and history of other disease. And when we educate CABG patients, education for diet, recurrence possibility of disease, management methods of operation site and risk symptom should be emphasized.

• 대한약리학회지
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• 제23권2호
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• pp.77-85
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• 1987

혈압과 심박수의 중추조절에 대한 복외측 연수의 choline성 수용체의 역할을 규명하기 위하여 본 연구를 실시하였다. urethane으로 마취한 흰쥐에서 신경흥분성 아미노산인 L-glutamate(300 ng/site)를 복외측 연수에 미세주사하여 승압부위 (VLPA)와 감압부위 (VLDA)를 각각 기능적으로 확인하였다. VLPA와 VLDA에 각각 여러가지 choline성 약물들과 choline성 수용체의 길항제들을 양측으로 미세주사하여 다음과 같은 결과를 관찰하였다. 1. VLPA에 ca.bachol(300 ng/site)를 미세주사한 후 현저한 혈압상승 및 빈맥이 일어났으며, 이 반응은 hexamethonium ($4\;{\mu}g/site$)의 전처치에 의하여 차단되지 않았다. 2. VLPA에 physostigmine (200 ng/site)과 oxot.emo.me (300 ng/site)을 미세주사한 후 각각 현저한 혈압상승이 일어났다. 3. VLPA에 atropine($4\;{\mu}g/site$)을 미세주사한 후 현저한 혈압하강 및 서맥이 일어났다. 4. VLDA에 acetylcholine(500 ng/site)과 dimethylphenylpipe.azinium (500 ng/site)을 미세주사한 후 각각 현저한 혈압하강 및 서맥이 일어났다. 5. VLDA에 acetylcholine(500 ng/site)을 미세주사한 후 유발된 혈압하강 및 서맥반응은 hexamethonium($4\;{\mu}g/site$) 전처치에 의하여 차단되었다. 이상의 결과로 보아 흰쥐의 복외측 연수의 승압부위에서는 muscarine성 수용체를 통하여 혈압상승 및 빈맥반응이 일어나고 감압부위에서는 nicotine성 수용체를 통하여 혈압하강 및 서맥 반응이 일어나는 것으로 사료된다.