• 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.

• Journal of Genetic Medicine
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• v.4 no.2
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• pp.160-166
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• 2007

Purpose : The ${\beta}$-adrenoceptors are pharmacologically classified into ${\beta}_1$-, ${\beta}_2$- and ${\beta}_3$-adrenoceptor. The gene of each subtype has polymorphisms related to their function (${\beta}_1$-adrenoceptor: Ser49Gly, ${\beta}_2$-adrenoceptor: Gln27Glu, ${\beta}_3$-adrenoceptor: Trp64Arg). The objectives of this study were to analyse the allelic and genotypic distribution of the representative polymorphism of ${\beta}$-adrenoceptors in preeclampsia and to investigate whether combined genotype of ${\beta}$-adrenoceptors may be associated with preeclampsia. Methods : Blood samples were collected from a Korean population (159 preeclamptic pregnancies and 168 normotensive pregnancies). The ${\beta}_1$-, ${\beta}_2$- and ${\beta}_3$-adrenoceptor genotypes was determined using polymerase chain reaction-restriction fragment length polymorphism. Results : There were no differences in allelic and genotypic distribution of ${\beta}_1$- and ${\beta}_2$-adrenoceptor polymorphisms between the two groups. However, the Arg allele of ${\beta}_3$-adrenoceptor polymorphism were more frequent in preecalmpsia than in controls (P<0.05, OR=1.57, 95% CI=1.01-2.46). Moreover, prevalence of genotype carrying heterozygote of ${\beta}_3$-adrenoceptor polymorphism was increased in preeclampsia compared with controls (P<0.05, OR 1.76, 95% CI 1.06-2.92). When combination of the three polymorphisms were evaluated, pregnancies with the particular combined genotype that is consisted of heterozygote of ${\beta}_1$-, ${\beta}_3$-adrenoceptor and wild homozygote of ${\beta}_2$-adrenoceptor (Ser/Gly, Gln/Gln, Trp/Arg), showed a significant increase in the risk of preeclampsia (P<0.05, OR=3.01, 95% CI 1.12-8.08). Conclusion : A particular combined genotype (Ser/Gly, Gln/Gln, Trp/Arg) of - adrenoceptors was associated with the risk of preeclampsia.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1784-1790
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• 2004

A series of 2-(3-chlorophenyl)-2-hydroxyethylamine derivatives containing a tetrahydrocarbazole linker were prepared and evaluated for their ${\beta}_3$-adrenoceptor agonistic activity. Several compounds showed potency comparable to CL-316243.

• Archives of Pharmacal Research
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• v.18 no.2
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• pp.129-132
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• 1995

Intravenous administration of O-acetyliervine (an alkaloid from Vertrum album) produced a dose-dependent (10-100 .mu.g/kg) fall in blood pressure and tachycardia in anaesthetized normotensive rats. Pretreatment of animals with propranolol (1mg/kg) abolished these cardiovascular responses of O-acetyljervine similar to that of isoprenaline $(1\mu/ml)$. In isolated tissue experiments, O-acetyljervine $(10-100\mu/ml)$ produced a dose-dependent relaxation of phenylephrine-induced contraction of the rabbit aorta. In guinea-pig spontaneously beating atria, it caused positive inotropic and chronotorpic responses in a dose-dependent fashion $(10-100\mu/ml)$. These responses were abolished in the presence of propranolol $(1\mu/ml)$ similar to that of isoprenaline. These results indicate that O-accetyljervine is adrenoceptor stimulant $(\beta_1\; and\;beta_2)$ like isoprenaline.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.1
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• pp.55-62
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• 1998

${\alpha},\;{\beta}-Adrenergics$, and calcium channels were known to be related to inducing cardiac hypertrophy. Recently, it was reported that the cardiac renin-angiotensin system (RAS) was an important factor in ventricular hypertrophy. The present study was aimed to investigate the effects of ${\alpha},\;{\beta}-adrenergic$, and calcium channel blockers that might be involved in the regulation of cardiac RAS. The reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of renin gene in the perfused rat heart. Changes in angiotensin converting enzyme (ACE) activity and cyclic AMP (cAMP) content which were thought to play a role in inducing cardiac hypertrophy were measured in the perfused rat heart. The expression of renin gene was not only increased by isoproterenol with metoprolol-pretreatment but also increased by vasopressin treatment in the presence of calcium channel blocker, nifedipine or verapamil. Either prazosin alone or norepinephrine with prazosin-pretreatment significantly increased the ACE activity. However, isoproterenol with metoprolol-pretreatment significantly decreased the ACE activity. On the other hand, the ACE activity was not changed by vasopressin, nifedipine, or verapamil treatments. The content of cAMP was significantly increased by either isoproterenol or vasopressin treatment. According to these results, renin gene expression was associated with ${\beta}2$ - adrenoceptor and calcium channel. ACE activity was associated with ${\alpha}-\;and{\beta}2$ - adrenoceptor. In conclusion, ${\beta}2$ - adrenoceptor was important in cardiac renin gene expression and ACE activity and ${\alpha},\;{\beta}$ -adrenergic, and calcium channel blockers might be involved in the regulation of cardiac RAS in a complicated way.

• Archives of Pharmacal Research
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• v.9 no.4
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• pp.219-222
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• 1986

Dose-dependent increasesin blood glucose were produced by epinephrine and clonidine in fasted male mice. Isoproterenol was ineffective in increasing blood glucose at lower doses ($10^{-8}M$/kg-$10^{-7}M$/kg); with higher dose ($10^{-6}M$/kg) the glucose level was increased. The hyperglycemia induced by epinephrine was inhibited by yobimbine, prazosin and propranolol, indicating that the hyperglycemic effect of epinephrine is mediated by alpha-1, alpha-2 and beta adrenoceptor. When clonidine (10$^{-6}$ M/kg) was administered simultaneously with sioproterenol ($10^{-6}M$/kg), an enhenced hyperglycemic effect was observed. The increment produced by clonidine plus isoproterenol was higher than that by clonidine alone. These increment produced by clonidine plus isoproterenol was higher than that by clonidine alone. These results suggest that stimulation of alpha-2 adrenoceptor may be reponsible for the exertion of the hyperglycemic effect by beta agonists in fasted mice.

• Biomolecules & Therapeutics
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• v.12 no.4
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• pp.215-220
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• 2004

In an attempt to develop new anti-diabetic agents, a series of aryloxypropanolamine derivatives was synthesized to serve as ${\beta}_3$ adrenoceptor agonists. Among these derivatives, 1-{1-methyl-3-[4-(2-methyl-2H-1,2,3,4-tetrazol-5-yl)phenyl]propylamino}-3-phenoxy-2-propanol (KR60886) possessed a high affinity for the ${\beta}_3$ adrenoceptor (Ki = 28 nM) and moderate affinities for ${\beta}_1$ and ${\beta}_2$ adrenoceptors (Ki = 95 nM and 100 nM, respectively). In addition, KR60886 stimulated cAMP production with an EC$_{50}$ of 0.4 ${\mu}M$, confirming its agonistic activity for the ${\beta}_3$ adrenoceptor. In vivo activities of KR60886 were examined by using a fat-fed/streptozotocin (STZ)-treated rat model and the ob/ob mouse model. Oral administration of KR60886 (10 mg/kg) for 3 days (b.i.d.) to fat-fed/STZ-treated rats significantly lowered plasma glucose levels and reduced plasma free fatty acid concentrations. Similarly, KR60886 treatment (10 mg/kg/day for 7 d) resulted in a reduction of plasma glucose concentrations in ob/ob mice. The present study suggests that KR60886 is a potent ${\beta}_3$ receptor agonist with in vivo anti-diabetic properties.

• The Korean Journal of Pharmacology
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• v.22 no.1 s.38
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• pp.24-33
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• 1986

To ascertain the existence of various adrenoceptors involved in active transport of sodium in the frog skin and to delineate their physiological roles, the influence of various adrenergic agonists and antagonists on the potential difference (PD), short-circuit current (SCC) and total skin conductance (TSC) of the isolated frog skin of Rana nigromaculata were investigated. PD and SCC were determined with Ussing's technique. Drugs were administered to the serosal side of the skin. Experimental results were summarized as follows: 1. The responses to norepinephrine (NE, $6{\times}10^{-8}-6{\times}10^{-5})M$), phenylephrine (PE, $5{\times}10^{-6}-5{\times}10^{-4}M$) and epinephrine (Epi, $5.5{\times}10^{-7}-5.5{\times}10^{-5}M$) were characterized by marked elevation of PD & SCC in dose-related fashion, but the maximal effect attained by Epi was less than those of NE and PE. 2. These increments of PD & SCC were significantly inhibited by prazosin $(2{\times}10^{-6}M)$, a speciflc ${\alpha}_1$-adrenoceptor blocker. The stimulatory effect on PD & SCC were completely abolished by phenoxybenzamine (PBZ, $3.3{\times}10^{-5}M$), an irreversible ${\alpha}$-adrenoceptor blocking agent. Furthermore, with a larger doses of Epi produced marked decline of PD & SCC after the PBZ pretreatment. 3. Isoproterenol (ISP), a ${\beta}$-adrenoceptor agonist, in concentrations ranging from $5{\times}10^{-7}$ to $5{\times}10^{-6}M$ produced dose-related decrease in PD & SCC, which could be abolished by pretreatment with propranolol $(4{\times}10^{-6}M)$, a specific ${\beta}$-adrenoceptor blocker. It was further noted that the effects of Epi on PD & SCC were markedly potentiated by Propranolol pretreatment. 4. Clonidine as well as guanabenz produced increases in PD & SCC and these effects were inhibited more specifically by prazosin pretreatment than by yohimbine. These results indicated that there exist in the frog skin two distinctive types of adrenoceptors, ${\alpha}$ and ${\beta}$, which roughly corresponds to those in mammals, and that the ${\alpha}$ type of adrenoceptors mediate the stimulation of PD & SCC, whereas ${\beta}$-adrenoceptors mediate the inhibition. However, based on evidence at hand, no conclusion could be drawn on the subtype of ${\alpha}$-adrenoceptors which is involved in the stimulation of sodium transport in the frog skin.

• Korean Journal of Veterinary Research
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• v.31 no.2
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• pp.171-178
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• 1991

Effects of catecholamines were investigated on isolated strips of the male cattle oesophageal groove. In the circular muscles of the bottom and longitudinal muscles of the lip. isometric tensions was recorded with isometric myograph in 25ml organ bath. The results were as follows: 1. The muscular activity was different in preparations from the two parts. In the longitudinal muscle from the lip, rhythmic contractions generally occurred. while in the circular muscle from the bottom they were not seen almost. 2. In the circular muscle of the bottom, the increased tone and biphasic contractions were caused by catecholamines. And these contractions were mediated through $\alpha$-excitatory adrenoceptor. Also circular muscle showed minor inhibitory response to catecholamines. And these effects were mediated through $\beta$-inhibitory adrenoceptor. But the circular muscle was more sensitive to the $\alpha$-excitatory effect than $\beta$-inhibitory effect. 3. In logitudinal muslce of the lip. rhythmic contractions were reduced or disappeared by catecholamines(especially propranolol) and these effects were mediated through $\beta$-adrenoceptor.

• Korean Journal of Veterinary Research
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• v.41 no.3
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• pp.327-332
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• 2001

In recent years, experimental evidence have been suggested that melatonin has either contractive or relaxing effects on the vascular smooth muscle in vitro. But the effect of melatonin on the cardiovascular system in vivo had been emphasized about the hypotensive effect. In this work, we found not only hypotensive effect but also hypertensive effect of melatonin in rats and attempted to determine the mechanism of these effects elicited by melatonin. Regadless of concentration, melatonin(0.002~5 mg/kg) produced increase in mean blood pressure (MBP) in 36% (54/150 cases) and decrease in mean blood pressure in 64%(96/150 cases). As a whole melatonin caused an increase or a decrease in MBP without compensatory decrease or increase in heart rate. The melatonin-induced hypertension was abolished by the pretreatment of phenoxybenzamine, a ${\alpha}$-adrenoceptor antagoninst. The melatonin-induced hypotension was abolished by the pretreatment of propranolol, a ${\beta}$-adrenoceptor antagonist, ODQ, a NO-sensitive guanylate cyclase inhibitor, or nifedipine, a L-type $Ca^{2+}$ channel blocker, but not by bilateral cervical vagotomy. The results indicate that melatonin-induced hypertension may be related to ${\alpha}$-adrenoceptor stimulation and melatonin-indued hypotension may be related to ${\beta}$-adrenoceptor stimulation, inhibition of $Ca^{2+}$ channel and/or activation of guanylate cyclase.