• Biomolecules & Therapeutics
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• v.1 no.1
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• pp.1-8
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• 1993

It has been known that calcium antagonists also inhibit the radioligand binding to muscarinic and $\alpha$-adrenergic receptors and, in case of verapamil, these inhibitions may play a role in the effects of verapamil on the heart. In this study, the effects of nicardipine, nifedipine, nimodipine, diltiazem and verapamil on the binding of [$^3H$]dihydroalprenolol (DHA) to dog cardiac ${\beta}$-adrenergic receptors were examined. A single uniform [$^3H$]DHA binding site ($K_D/= 5nM\;and\;B_{max}=2600$ fmol/mg protein) was identified in dog cardiac sarcolemma. [$^3H$]DHA binding was not affected by the usual therapeutic concentrations of these calcium antagonists (nanomolar range) but in the "nonspecific"concentration ranges ($28-180{\mu}m$) these drugs inhibited [$^3H$]DHA binding to $\beta$-adrenergic receptors. Nicardipine, nifedipine, nimodipine and diltiazem competed for [$^3H$]DHA binding to ${\beta}$-adrenergic receptors with dissociation constants ($K_i$) of $28{\mu}m,\' 74{\mu}m, 39{\mu}m \;and \;35{\mu}m,$ respectively. Verapamil ($K_i=176.5 {\mu}m$) was less potent inhibitor than other drugs and this inhibition was noncompetitive; the maximal binding capacity ($B_{max}$) $300 {\mu}m$ verapamil without change in the apparent dissociation constant (4K_D$) for DHA. These results indicate that the inhibitory action of calcium antagonists at high concentrations on ${\beta}$-adrenergic receptors is not involved in the therapeutic effects of these drugs by the calcium channel blocking action.

• International Journal of Oral Biology
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• v.46 no.1
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• pp.39-44
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• 2021

This study aimed to investigate whether neurotransmitter receptors in the nervous system were also expressed in oral keratinocytes. Expressions of various neurotransmitter receptor genes in immortalized mouse oral keratinocyte (IMOK) cells were examined by reverse transcriptase polymerase chain reaction. IMOK cells expressed calcitonin gene-related peptide (CGRP) receptor subunit genes Ramp1 and Ramp3 and glutamate receptor subunit genes Grina, Gria3, Grin1, Grin2a, and Grin2d. Moreover, IMOK cells expressed Adrb2 and Chrna5 that encode beta 2 adrenergic receptor and cholinergic receptor nicotinic alpha 5 for sympathetic and parasympathetic neurotransmitters, respectively. The expression of Bdkrb1 and Ptger4, which encode receptors for bradykinin and prostaglandin E2 involved in inflammatory responses, was also observed at low levels. Expressions of Ramp1 and Grina in the mouse gingival epithelium were also confirmed by immunohistochemistry. When the function of neurotransmitter receptors expressed on IMOK cells was tested by intracellular calcium response, CGRP, glutamate, and cholinergic receptors did not respond to their agonists, but the bradykinin receptor responded to bradykinin. Collectively, oral keratinocytes express several neurotransmitter receptors, suggesting the potential regulation of oral epithelial homeostasis by the nervous system.

• The Korean Journal of Pharmacology
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• v.2 no.1 s.2
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• pp.41-48
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• 1966

The author studied the adrenotropic receptors of the non-pregnant uteri of the rabbit and rat, using epinephrine (alpha and beta activator), phenoxybenzamine(alpha blocking agent) and nethalide (beta blockade), and obtained the following results: 1. The spontaneous motility of isolated non-pregnant uteri from rabbits were stimulated by epinephrine, whereas that of isolated non-pregnant rat uterus was inhibited by epinephrine. 2. Both alpha and beta adrenergic receptors were present in the uterine muscle of both animals. 3. In the non-pregnant rabbit uterus, alpha receptors were predominant, whereas in the non -pregnant rat uterus, beta receptors preponderated over alpha receptors.

• The Korean Journal of Malacology
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• v.25 no.1
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• pp.15-22
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• 2009

Because it is known that bivalve hearts contain various modulatory systems activated by neuroendocrine substances, it was examined whether different classes of endogenous and synthetic drugs of neuroendocrinological importance can influence cardiac functions of the Pacific oyster Crassostrea gigas. Cholinergically active agents acetylcholine and carbachol increased heart rates while diminishing cardiac contractility. Adrenergically active substances norepinephrine (NE) and epinephrine (Epi) also induced heart rate increase and contractility decrease. An $\alpha_1$-adrenergic receptor-selective agonist phenyephrine (PE) failed to modulate either parameter. The Epi-induced heart rate increase and contractile depression were both blocked significantly by non-selective $\beta_1/\beta_2$-adrenergic antagonist propranolol. A $\beta_1$-selective antagonist atenolol prevented Epi-induced heart rate decrease but not the contractile depression, suggesting possible $\beta_2$ receptors for Epi-induced contractile depression. The three autacoids examined exerted discrete responses: histamine increased heart rate and depressed contraction; $\gamma$-amino-butyric acid increased both parameters; serotonin failed to change either parameter. The 5 piscine anesthetic agents examined, MS-222, benzocaine, quinaldine, urethane, pantocaine and pentobarbital, all failed to influence the cardiac function of oysters. Collectively, activities of neuroendocrinologically acting agents in mammals showed unexpected and distinct activities from those in mammalian cardiovascular systems. These results obtained from substances of different physiological functions can serve as a basis for understanding neuroendocrine control of the heart function in Pacific oyster.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.146-146
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• 1998

The present study was designed to examine the effect of total ginseng saponin on contractile responses of vasoconstrictors in the rat aorta. Phenylephrine (an adrenergic ${\alpha}$$_1$-receptor agonist) and high potassium (a membrane depolarizing agent) caused greatly contractile responses in the rat aorta, respectively. However, in the presence of total ginseng saponin (600 $\mu\textrm{g}$/$m\ell$), the contractile responses of phenylephrine (10$\^$-5/ and 10$\^$-7/ M) and high potassium (3.5 ${\times}$ 10$\^$-2/ and 5.6 ${\times}$ 10$\^$-2/ M) were markedly potentiated whereas prostaglandin F$\sub$2${\alpha}$/ (5 ${\times}$ 10$\^$-6/ M)-induced contractile response was not affected. The contractile responses induced by phenylephrine (10$\^$-5/ M) and high potassium (3.5 ${\times}$ 10$\^$-2/ M) even in the presence of total ginseng saponin (600 $\mu\textrm{g}$/$m\ell$) were greatly inhibited by the pretreatment of nicardipine (10$\^$-6/ M), a calcium channel blocker. Taken together, these experimental results suggest that total ginseng saponin can enhance the contractile responses evoked by stimulation of adrenergic ${\alpha}$$_1$-receptor and the membrane depolarization in the rat aorta, which seems to be associated to calcium influx.

• Korean Journal of Veterinary Research
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• v.31 no.3
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• pp.253-258
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• 1991

The aims of this study were to investigate the effect of adenosine triphosphate (ATP), which has been known as the neurotransmitter of nonadrenergic, noncholinergic nerves, and the source of $Ca^{\sharp}$ in the effect of ATP on the isolated renal artery of pig. The results of this study were summarized as follows: 1. ATP caused the contraction and the contractile responses were increased in a dose-dependent manner between the concentration of ATP $2{\times}10^{-3}M$ and $10^{-2}M$ on the isolated renal artery of pig. 2. The contractile responses induced by ATP $(5{\times}10^{-3}M)$ were not blocked by pretreatment with cholinergic receptor blocker (atropine, $10^{-6}M$), $\alpha$-adrenergic recptor blocker(phentolamine, $10^{-6}M$) or $\beta$-adrenergic receptor blocker (propranolol, $10^{-6}M$), and $H_1$-receptor blocker (pyrilamine, $10^{-6}M$) or $H_2$-receptor blocker (cimetidine, $10^{-6}M$) on the isolated renal artery of pig. 3. The contractile responses induced by ATP $(5{\times}10^{-3}M)$ were not appeared in $Ca^{\sharp}$-free medium. As the concentration of $Ca^{\sharp}$ in $Ca^{\sharp}$-free medium was increased, the contractile responses induced by ATP $(5{\times}10^{-3}M)$ were enhanced but were completely inhibited by pretreatment with $Ca^{\sharp}$-channel blocker, papaverine $(5{\times}10^{-5}M)$ or verapamil $(5{\times}10^{-5}M)$ on the isolated renal artery of pig.

• Korean Journal of Biological Psychiatry
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• v.22 no.4
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• pp.179-186
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• 2015

Objectives Adrenergic alpha 1 and 2 receptors work as pathways to control the serotonergic neuron moderation and mirtazapine acts as antagonist of these receptors. The adrenoreceptor alpha 1a (ADRA1A) gene, which encodes adrenergic alpha 1 receptor, has Arg-347Cys genetic polymorphism and the polymorphism has strong relationship with many neuro-psychiatric diseases. In this study, we explored the relationship between ADRA1A R347C polymorphism and mirtazapine treatment response in Koreans with major depression. Methods 352 patients enrolled in this study, and the symptoms were evaluated by 17-item Hamilton Depression Rating (HAMD-17) scale. After 1, 2, 4, 8, and 12 weeks of mirtazapine treatment, the association between ADRA1A R347C polymorphism and remission/response outcomes was evaluated. Results Treatment response to mirtazapine was significantly better in T allele carriers than C allele homozygotes after 12 weeks of mirtazapine monotherapy. The percentile decline of HAMD-17 score in T allele carriers was larger than that of C allele homozygotes. ADRA1A R347C genotypes were not significantly associated with remission. Conclusions The result showed that treatment response to mirtazapine was significantly associated with ADRA1A R347C genetic polymorphism. T allele carriers showed better treatment response than C allele homozygotes. It can be supposed that T allele carriers have a trend of better treatment response to mirtazapine monotherapy.

• The Korean Journal of Pharmacology
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• v.5 no.2
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• pp.115-119
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• 1969

The authors studied the adrenotropic receptors of isolated urinary bladder from Sebastes inermis, using adrenergic activators such as epinephrine, nor-epinephrine, isoproterenol and phenylephrine and adrenergic blocking agents such as phenoxybenzamine, pronethalol and propranolol. The studies have revealed the following results. 1) The spontaneous motility of isolated bladder from Sebastes inermis was inhibited by epinephrine nor-epinephrine, isoproterenol and phenylephrine. 2) The inhibitory effect of phenylephrine on the Sebastes inermis bladder was blocked by phenoxybensamine. 3) The inhibitory effect of isoproterenol was blocked by pronethalol and propranolol. 4) The effect of epinephrine and nor-epinephrine on the Sebastes inermis bladder was usually not blocked by either kind of blocking agent alone, but was blocked by a combination of ${\alpha}\;and\;{\beta}$ blockades. 5) It is, therefore, concluded that the Sebastes inermis bladder has alpha and that both receptors, and that both receptors subserve retaxation or inhibition.

• The Korean Journal of Physiology
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• v.20 no.1
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• pp.9-15
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• 1986

The effect of dopamine on the propagation and the frequency electrical activities (slow wave) of the stomach was studied in isolated stomach muscle strips of 145 cats, The gastric slow wave monopolarly recorded by four capillary electrodes (Ag-AgCl) in Krebs-Ringer solution $(ph\;7.4,\;temperature\;36{\pm}0.5^{\circ}C)$ bubbled with 5% $CO_2$ in $O_2$. Dopamine caused concentration-dependent changes of direction of slow wave propagation with decline in development of irregular propagation by domperidone pretreatment. Dopamine also increased the variation of slow wave frequency concentration-dependently. The variation of slow wave frequency induced by dopamine was significantly inhibited by pretreatment with domperidone and phentolamine but not with propranolol, hexamethonium and tetrodotoxin. It is therefore suggested that dopamine plays a role in the genesis of gastric electrical abnormality acting on dopamine receptors and partly on ${\alpha}-adrenergic$ receptors in cats.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.9
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• pp.1256-1264
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• 2016

Adrenergic, alpha-1B-, receptor (ADRA1B) and peroxisome proliferator-activated receptor gamma, coactivator 1 beta (PPARGC1B) genes are involved in regulation of hen ovarian development. In this study, these two genes were investigated as possible molecular markers associated with hen-housed egg production, egg weight (EW) and body weight in Chinese Dagu hens. Samples were analyzed using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) technique, followed by sequencing analysis. Two novel single nucleotide polymorphisms (SNPs) were identified within the candidate genes. Among them, an A/G transition at base position 1915 in exon 2 of ADRA1B gene and a T/C mutation at base position 6146 in the 3'- untranslated region (UTR) of PPARGC1B gene were found to be polymorphic and named SNP A1915G and T6146C, respectively. The SNP A1915G (ADRA1B) leads to a non-synonymous substitution (aspartic acid 489-to-glycine). The 360 birds from the Dagu population were divided into genotypes AA and AG, allele A was found to be present at a higher frequency. Furthermore, the AG genotype correlated with significantly higher hen-housed egg production (HHEP) at 30, 43, 57, and 66 wks of age and with a higher EW at 30 and 43 wks (p<0.05). For the SNP T6146C (PPARGC1B), the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher HHEP at 57 and 66 wks of age and EW at 30 and 43 wks (p<0.05). Moreover, four haplotypes were reconstructed based on these two SNPs, with the AGTC haplotype found to be associated with the highest HHEP at 30 to 66 wks of age and with higher EW at 30 and 43 wks (p<0.05). Collectively, the two SNPs identified in this study might be used as potential genetic molecular markers favorable in the improvement of egg productivity in chicken breeding.