• 약학회지
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• 제37권4호
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• pp.397-407
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• 1993

The muscarinic antagonist l-[benzilic-4,4'-$^3H$]quinuclidinyl benzilate([$^3H$]QNB) bound to a single class of muscarinic receptor with high affinity in guinea pig ileal membranes. The $K_{D}$ and B$_{max}$ values for [$^3H$]QNB calculated from analysis of saturation isotherms were 54 pM and 156fmol/mg, respectively. H$_{1}$-blockers inhibited [$^3H$]QNB binding to ileal membranes with $K_{i}$ values ranged from 0.008 $\mu{M}$ to 1.6 $\mu{M}$. The pseudo-Hill coefficients of H$_{1}$-blockers for inhibition of [$^3H$]QNB binding to the ileal membranes were close to unit. The $K_{i}$ values for H$_{1}$-blockers were similar to the $K_{M}$ values calculated by Schild plot of functional data obtained from inhibition of the carbachol-induced contraction in guinea-pig ileum, suggesting that binding of H$_{1}$-blockers vs [$^3H$]QNB in ileal membranes represents an interaction with a receptor of physiological relevance. The $K_{H}$ values of H$_{1}$-blockers for H$_{1}$-receptor estimated from inhibition of the histamine-induced contraction were the range of 0.15 nM to 56.5 nM. The $K_{M}$/K$_{H}$ ratio of H$_{1}$-blockers varied over a wide range of 3 to 2300. Thus, the antihistaminic potencies of H$_{1}$-blockers do not correlate with their antimuscarinic potencies, which suggest that antihistamines have different antimuscarinic potencies in therapeutic blood levels causing similar antiallergic effect. Among 13 traditional antihistaminics examined in this study, drug having the highest and the lowest $K_{M}$/K$_{H}$ ratio is triprolidine and diphenidol, respectively. The present results demonstrate that the antimuscarinic property of antihistamines is not necessary for their antiallergic effect, and data on the affinity of antihistamines for muscarinic and H$_{1}$-receptors can be an important parameter in the selection and evaluation of these drugs.

• 대한임상독성학회지
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• 제16권2호
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• pp.165-171
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• 2018

An overdose of antihypertensive agents, such calcium channel blockers (CCBs) and angiotensin II receptor blocker (ARBs), and the antihyperglycemic agent, metformin, leads to hypotension and lactic acidosis, respectively. A 40-year-old hypertensive and diabetic man with hyperlipidemia and a weight of 110 kg presented to the emergency room with vomiting, dizziness, and hypotension following an attempted drug overdose suicide with combined CCBs, ARBs, 3-hydroxy-3-methylglutaryl-coemzyme A reductase inhibitors, and metformins. A conventional medical treatment initially administered proved ineffective. The treatment was then changed to simultaneous extracorporeal membrane oxygenation (ECMO) and continuous renal replacement therapy (CRRT), which was effective. This shows that simultaneous ECMO and CRRT can be an effective treatment protocol in cases of ineffective conventional medical therapy for hypotension and lactic acidosis due to an overdose of antihypertensive agents and metformin, respectively.

• 약학회지
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• 제34권4호
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• pp.224-237
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• 1990

A single uniform population of specific, saturable, high affinity binding site of $[^3H]QNB$ guinuclidinyl benzilate(QNB) was identified in the rat cerebral microsomes. The Kd value(37.2 pM) for $[^3H]QNB$ calculated from the kinetically derived rate constants was in agreement with the Kd value(48.9 pM) determined by analysis of saturation isotherms at various receptor concentrations. Dimenhydrinate(DMH), histamine $H_1-blocker$, increased Kd value for $[^3H]QNB$ QNB without affecting the binding site concentrations and this effect resulted from the ability of DMH to slow $[^3H]QNB-receptor$ association. Pirenzepine inhibition curve of $[^3H]QNB$ binding was shallow(nH = 0.52) indicating the presence of two receptor subtypes with high ($M_1-site$) and low($M_2-site$) affinity for pirenzepine. Analysis of these inhibition curves yielded that 68% of the total receptor populations were of the $M_1-subtype$ and the remaining 32% of the $M_2-subtype$. Ki values for the $M_1-$ and $M_2-subtypes$ were 2.42 nM and 629.3 nM, respectively. Ki values for $H_1-blockers$ that inhibited $[^3H]QNB$ binding varied with a wide range ($0.02-2.5\;{\mu}M$). The Pseudo-Hill coefficients for inhibition of $[^3H]QNB$ binding by most of $H_1-blockers$ examined except for oxomemazine inhibition of $[^3H]QNB$ binding were close to one. The inhibition curve for oxomemazine in competition with $[^3H]QNB$ was shallow(nH = 0.74) indicating the presence of two receptor populations with different affinities for this drug. The proportion of high and low affinity was 33:67. The Ki values for oxomemazine were $0.045{\pm}0.016\;{\mu}M$ for high affinity and $1.145{\pm}0.232\;{\mu}M$ for low affinity sites. These data indicate that muscarinic receptor blocking potency of $H_1-blockers$ varies widely between different drugs and that most of $H_1-blockers$ examined are nonselective antagonist for the muscarinic receptor subtypes, whereas oxomemazine might be capable of distinguishing between subclasses of muscarinic receptor.

• 약학회지
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• 제58권2호
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• pp.141-149
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• 2014

Background: Oriental lifestyle for treating diseases has been developed and well-accepted for a long time among Koreans. Sasang Constitution theory, originated from Korean traditional medicine, suggests that medication treatment should be differentiated by each patient's body classification (So-yang [SY], So-eum [SE], Tae-yang [TY], and Tae-eum [TE]), in contrary to western medicine's theory that medication should be applied equally by disease indication without such classification. However, the pharmacotherapeutic outcomes of these theories have not been compared to date. In this study, we aimed to compare the two theories by evaluating blood pressure (BP), which is lowered as a therapeutic outcome, among hypertensive patients taking angiotensin II receptor blockers (ARBs) or calcium channel blockers (CCBs), two most commonly used antihypertensive classes in Korea. Methods: From April 2006 to June 2012, we retrospectively collected data on hypertensive patients with Sasang Constitution classification at Kyunghee University Hospital at Gangdong, one of the East-West collaborative medical centers in Korea. We collected information on age, gender, underlying diseases, antihypertensive drugs (ARB, CCB, ARB+CCB), and BP by reviewing the electronic medical records. We excluded patients with missing blood pressure at baseline or follow-up, or those who had a change in their antihypertensive drug class during follow-up. Results: We selected a total of 573 patients (SY: 165, SE: 158, TY: 0, TE: 250). Baseline BPs were on average 139.0/82.0 mmHg for SY, 137.8/78.5 mmHg for SE, and 138.7/79.2 mmHg for TE. In all three groups, CCBs were the most prescribed, followed by combination therapy with ARB+CCB, then ARBs. BP reduction after 1 month of initial medication was significantly different among the drug classes, but not in Sasang constitutional classification (ARB [SY: -12.4/-4.7, SE: -12.3/-2.5, TE: -8.6/-1.8], CCB [SY: -12.3/-5.4, SE: -13.0/-2.3, TE: -10.8/-6.0], ARB+CCB [SY: -15.6/-6.7, SE: -18.4/-8.1, TE: -20.2/-6.7], drug [$P{\leq}0.05$/P>0.05], constitutional type [P>0.05/P>0.05]). Conclusion: We observed significant differences in reduction of blood pressure by classes of drugs (ARB+CCB>CCB>ARB) but not by Sasang constitutional classification. Therefore, current approach of antihypertensive pharmacotherapy assisted by Western medicine is appropriate for treatment of hypertension. However, further larger scale or prospective studies are required in order to confirm these results.

• Korean Circulation Journal
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• 제52권3호
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• pp.173-197
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• 2022

Treatment options for patients with heart failure (HF) with reduced ejection fraction (HFrEF) have expanded considerably over the past few decades. Whereas neurohormonal modulation remains central to the management of patients with HFrEF, other pathways have been targeted with drugs that have novel mechanisms of action. The angiotensin receptor-neprilysin inhibitors (ARNIs) which enhance levels of compensatory molecules such as the natriuretic peptides while simultaneously providing angiotensin receptor blockade have emerged as the preferred strategy for inhibiting the renin angiotensin system. Sodium glucose cotransporter 2 (SGLT2) inhibitors which were developed as hypoglycemic agents have been shown to improve outcomes in patients with HF regardless of their diabetic status. These agents along with beta blockers and mineralocorticoid receptor antagonists are the core medical therapies for patients with HFrEF. Additional approaches using ivabradine to slow heart rate in patients with sinus rhythm, the hydralazine/isosorbide dinitrate combination to unload the heart, digoxin to provide inotropic support and vericiguat to augment cyclic guanosine monophosphate production have been shown in well-designed trials to have beneficial effects in the HFrEF population and are used as adjuncts to the core therapies in selected patients. This review provides an overview of the medical management of patients with HFrEF with focus on the major developments that have taken place in the field. It offers prospective of how these drugs should be employed in clinical practice and also a glimpse into some strategies that may prove to be useful in the future.

• 대한기관식도과학회지
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• 제4권1호
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• pp.64-72
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• 1998

This study aimed at observing the effect of diazepam on the contractility of trachealis muscle isolated from canine trachea, possible involvement of central or peripheral type benzodiazepine receptor, and the calcium related mechanism of action of diazepam. Trachealis muscle strips of 15 mm long were suspended in an isolated organ bath containing 1 ml of physiologic salt solution maintained at $37^{\circ}C$, and aerated with 95% $O_2$ /5% $CO_2$. Isometric myography was performed. Diazepam reduced the basal tone concentration dependently, and this inhibitory action was not affected by neither flumazenil, a central benzodiazepine receptor antagonist, nor PK11195, a peripheral benzodiazepine receptor antagonist. Pretreatment with diazepam showed the inhibitory effect on the concentration-response curves to agonists such as bethanechol, 5-hydroxytryptamine and histamine. Diazepam also caused concentration-related inhibition of contraction with potassium chloride 30 mM. The effect of diazepam on the basal tone and potassium chloride-induced contraction with calcium channel blockers were compared. Similar results were obtained in canine trachealis with verapamil, nifedipine and diltiazem. These results suggest that diazepam relax an airway muscle not via specific receptors but by a similar action as calcium channel blockers in canine trachealis muscle.

• 약학회지
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• 제32권2호
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• pp.101-111
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• 1988

$[^3H]$ Quinuclidinyl benzilate(QNB) binding assays were performed in the dog ventricular sarcolemma fraction enriched approx. 32-fold in sarcolemma compared to the starting homogenate to elucidate the effect of antihistaminics on cardiac muscarinic receptor. Chlorpheniramine(CHP) inhibited specific binding of $[^3H]$QNB and delayed the equilibrium binding. The rate constants at $37^{\circ}C$ for formation and dissociation of the QNB receptor complex were $0.38{\times}10^9\;M^{-1}$ and $1.6{\times}10^{-2}\;min^{-1}$, respectively. The mean value for the dissociation constant from the pairs of the rate constants was 43. 2 pM and this value was similar to the value(44.8pM) determined from Scatchard analysis. CHP decreased association rate constant, indicating increase in $K_D$ value. Decrease in affinity without affecting the binding site concentration$(B_{max})$ for $[^3H]$QNB binding by CHP was also demonstrated by Scatchard analysis. $K_i$ values for $H_i$-blockers that inhibited specific $[^3H]$QNB binding were $0.02{\sim}4.8{\mu}M$. Cimetidine with $K_i$ value of $230{\mu}M$, however, was ineffective in displacing $[^3H]$QNB binding at concentration of $50{\mu}M$. The Hill coefficient for $H_1$-blockers were about one. The results indicate that $H_1$-antihistaminics inhibit $[^3H]$ QNB binding by interaction with myocardiac muscarinic cholinergic receptor and anticholinergic side effects of these drugs are mainly due to this receptor blocking mechanism.

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2707-2712
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• 2009

5-$HT_{3}$ receptor;5-$HT_{3A}$ receptor channel activity;Novel 5-$HT_{3}$ receptor channel current blockers;Chlorophenyl substituted piperazinylethylaminomethylpyrazoles; The 5-$HT_{3A}$ receptors are one of ligand-gated ion channels and are known to be involved in visceral pain, anxiety, or anticancer agent-induced nausea and vomiting. In present study, we designed novel skeletons based on the developed 5-$HT_{3}$ receptor antagonists and evaluated their effects on 5-$HT_{3A}$ receptor channel currents ($I_{5-HT}$) of a series of pyrazole derivatives having N-chlorophenylpiperazine functionality (6-9). We found that most of N-p-chlorophenyl substituted piperazinyl-pyrazole derivatives (7b, 7c, 7e and 7h) exhibited the high potency for the inhibition of $I_{5-HT}$, whereas the compound without chloride (6) or with m-chlorophenyl group (a serious of 8 and 9) showed the low potency. These result indicate that p-chlorophenyl group is might play an important role for increasing the inhibitory potency on $I_{5-HT}$.

• 한국임상약학회지
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• 제32권2호
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• pp.125-132
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• 2022

Background: Fixed-dose combinations have the advantage of improving patient compliance, but may increase the risk of duplicate prescriptions. As the use of fixed-dose combination antihypertensives increases, it is necessary to investigate the current status of class duplication prescriptions (CDP) in patients taking fixed-dose combination antihypertensives in Korea and to identify factors associated with CDP. Methods: We conducted a retrospective observational study using nationally representative claim data. Hypertensive patients aged 20 years or older taking fixed-dose combination antihypertensives were extracted. Among these patients, patients with CDP were identified. A chi-square test was applied to determine the differences between patients with CDP and non-CDP. The associated factors of CDP were identified through multiple logistic regression. Results: Of the 74,165 patients who were prescribed fixed-dose combination antihypertensives, 426 patients (0.6%) with CDP were identified. The most common antihypertensive class associated with CDP was calcium channel blockers (194 patients, 45.5%), followed by angiotensin II receptor blockers (136 patients, 31.9%). Patients aged 75 years or older (odds ratio [OR] 1.83, 95% confidence interval [CI] 1.02-3.52), chronic kidney disease (OR 4.45, 95% CI 2.15-8.25), chronic heart failure (OR 2.71, 95% CI 1.93-3.72), coronary artery disease (OR 2.22, 95% CI 1.60-3.03) and Medical Aid/Patriots and Veterans Insurance (OR 1.49, 95% CI 1.04-2.07) were significantly associated with increased CDP. Conclusions: The factors associated with CDP were the elderly, comorbidities, and low socioeconomic status. Since CDP can result in negative clinical outcomes, active intervention by the pharmacist is warranted.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8031-8039
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• 2016

Background: Preclinical studies have demonstrated that ${\beta}$-adrenergic receptor antagonists could improve the prognosis of breast cancer. However, the conclusions of clinical and pharmacoepidemiological studies have been inconsistent. This review was conducted to re-assess the relationship between beta-adrenoceptor blockers and breast cancer prognosis. Materials and Methods: The literature was searched from PubMed, EMBASE and Web of Nature (Thompson Reuters) databases through using key terms, such as breast cancer and beta-adrenoceptor blockers. Results: Ten publications met the inclusion criteria. Six suggested that receiving beta-adrenoceptor blockers reduced the risk of breast cancer-specific mortality, and three of them had statistical significance (hazard ratio (HR)=0.42; 95% CI=0.18-0.97; p=0.042). Two studies reported that risk of recurrence and distant metastasis (DM) were both significantly reduced. One study demonstrated that the risk of relapse-free survival (RFS) was raised significantly with beta-blockers (BBS) (HR= 0.30; 95% CI=0.10-0.87; p=0.027). One reported longer disease-free interval (Log Rank (LR)=6.658; p=0.011) in BBS users, but there was no significant association between overall survival (OS) and BBS (HR= 0.35; 95% CI=0.12-1.0; p=0.05) in five studies. Conclusions: Through careful consideration, it is suggested that beta-adrenoceptor blockers use may be associated with improved prognosis in breast cancer patients. Nevertheless, larger size studies are needed to further explore the relationship between beta-blocker drug use and breast cancer prognosis.