• 대한약침학회지
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• 제16권1호
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• pp.37-42
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• 2013

Objective: The aim of this experiment was to investigate the effect and the mechanism of Geumgoeshingi-whan (GGSGW) Pharmacopuncture at the acupoint GV 4 on the blood pressure in spontaneously hypertensive rats (SHR). Methods: SHR were injected with normal saline solution (Control-SHR group)or GGSGW Pharmacopuncture (GGSGW-SHR group) at the acupoint GV 4. The systolic arterial blood pressure and renal parameters were measured for two weeks. Results: The systolic arterial blood pressure was decreased significantly after GGSGW Pharmacopuncture at the acupoint GV 4 in SHR, followed by a significant rise in creatine clearance. The plasma levels of aldosterone were decreased significantly after GGSGW Pharmacopunctureas were the plasma levels of atrial natriuretic peptide (ANP). Conclusion: These results suggest that the blood pressure was decreased significantly after GGSGW Pharmacopuncture at the acupoint GV 4 in SHR and that the depressor response of the blood pressure was related to decreases in the plasma levels of aldosterone and ANP.

• Archives of Pharmacal Research
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• 제13권1호
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• pp.55-63
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• 1990

An attempt was made to investigate the effect of intracerebroventricular 5-hydroxytrypatamine (5-HT) on the cardiovascular system in urethane-anesthetized rabbit and to elucidate the mechanism of its action. 5-HT given into a lateral ventricle caused clearly a dose-dependent decrease inboth arterial blood pressure and in heart rate. The bradycardia and hypotension induced by 5-HT were significantly attenuated by the prior injection of ketanserin, cyproheptadine or clonidine. Pretreatment of atropine with bilateral vagotomy did not affect both bradycardia and hypotension. Propranolol weakened markedly the breadcardia of 5-HT but did not influence the depressor response of 5-HT. These experimental results suggest that intraventricular 5-HT cause the hypotension and bradyardia in rabbits through the stimulation of serotonergic receptors in brain, which is seemed to be associated to inhibition of sympathetic tone.

• Journal of Acupuncture Research
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• 제15권2호
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• pp.349-356
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• 1998

The aim of the experiments was to investigate the effect of Semen Cuscutae aqua-acupuncture at the meridian point BL 20(脾兪) and BL 23(賢兪) on the blood pressure, plasma renin activity, plasma levels of aldosterone and atrial natriuretic peptide (ANP) in spontaneously hypertensive rats (SHR). The results of this study were as follows: 1. Systolic blood pressure was decreased significantly after Semen Cuscutae aqua-acupuncture at the meridian point BL 20, BL 23. 2. Plasma renin activity was increased significantly after Semen Cuscutae aqua-acupuncture at meridian point BL 23, BL 20. 3. Plasma levels of aldosterone was increased significantly after Semen Cuscutae aqua-acupuncture at the meridian point BL 20. 4. Plasma levels of atrial natriuretic peptide (ANP) was increased significantly after Semen Cuscutae aqua-acupuncture at the meridian point BL 23, but it was decreased significantly after Semen Cuscutae aqua-acupuncture at the meridian point BL 20. These results suggest that the changes of the depressor response after Semen Cuscutae aqua-acupuncture at the meridian point BL 20, BL 23 are related to the changes of the plasma renin activity, plasma levels of atrial natriuretic peptide (ANP) and aldosterone.

• 대한약리학회지
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• 제15권1_2호
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• pp.45-56
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• 1979

With a view to searching after a new antihypertensive or hypotensive agents in the botanical crude plants, authors intended to reevaluate several natural products caltivated in Korea. This experiment was undertaken to compare pharmacogical actions of Machilus thunbergii Siebold et Zuccarini with those of Magnolia obovata Thunberg in anesthetized rats and in normal mice. Machilus thunbergii Sieb. et Zucc., a tree belonging to the Lauraceae family, is caltivated at Ull-ung Do, and their cortecies have been used as folk medicine mingled with those of Magnolia obovata Thunberg. These two cortecies have teen also applied in chinese medicine, it was advocated that these cortecies exerted good therapeutic effects on gastritis, convulsive abdominal pain, nausea, vomiting and urinary tract disorders. Therefore, we intended to determine the pharmacological action of two palnt of different family each other, especially their effects on blood pressure and heart rate, and also their mechanism of action were observed. We studied their action with extracts of hexane(MTHE), ether(MTEE), methanol(MTME) and water(MTWE) from Machilus thunhergii Sieb. et Zucc., and also fractionations of methanol(MOME), chloroform(MOCE) and water(MOWE) from Mapolia obovata Thunberg. The results of this experiment were as follows; 1) MTME, when intravenously administered to rats, elicited the significant hypotensive responses dependent on the administered dosage. 2) MOWE was also exhibited the hypotensive effect dependent on the treated dose. 3) Depressor effect of MTME was blocked by pretreatment with hexamethonium. 4) The hypotensive response of MOWE was blocked by pretreatment with hexamethonium or hrdralazine. 5) HTME and MOWE were also observed the anticonvulsive effect and sedative effect. These results suggested that MTME may induce the hypotensive response via central sympathetic effect, but the site of action in brain are not clarified, and the hypotensive effect of MOWE may be due to dual mechanism of central sympathetic action and direct vasodilation of blood vessel.

• 대한약리학회지
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• 제13권2호
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• pp.19-34
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• 1977

1) 마취가토(痲醉家兎) 및 묘(猫)에서 경뇌막외강(硬腦膜外腔)을 통(通)한 가압방법(加壓方法)으로 두개내압상승(頭蓋內驅上昇)과 혈압(血壓) 및 심박(心搏)과의 관계(關係)를 조사(調査)하였다. 2) 양동물(兩動物)에서 두개내압(頭盞內壓)을 상승(上昇)시켜 두개내압(頭蓋內壓)과 혈압(血壓)의 차(差)가 아주 적어지면 현저(顯著)한 혈압상승(血壓上昇)이 나타났다. 3) 양동물(兩動物)에서 두개내압(頭盞內壓)이 혈압(血壓)보다 높아지면 현저(顯著)한 혈압하강(血壓下降)과 현저(顯著)한 일시적(一時的)인 심박감소(心搏減少)가 나타났다. 4) Reserpine 처리동물(處理動物)에서는 두개내압상승(頭蓋內驅上昇)은 혈압하강(血壓下降), 심박감소(心搏減少)를 일으켰다. 5) 6-Hydroxydopamine 처리(뇌내)동물(處理(腦內)動物)에서는 두개내압상승(頭蓋內驅上昇)에 의한 혈압상승(血壓上昇)은 비처리동물(非處理動物)에 비(比)하여 약(弱)하였다. 6) Reserpine 처리동물(處理動物)의 측뇌실내(側腦室內)에 norepinephrine을 투여(投與)한 후(後)에는 두개내압상승(頭蓋內驅上昇)은 현저(顯著)한 혈압상승(血壓上昇)을 일으켰다. 7) 두개내압상승(頭蓋內驅上昇)에 의한 혈압상승(血壓上昇)은 두개내압상승(頭蓋內驅上昇)으로써 뇌내(腦內) noradrenergic neuron이 자극(刺戟)되여 norepinephrine 유리(遊離)가 증가(增加)한 결과(結果) 일어나는 것으로 추리(推理)하였다.

• The Korean Journal of Physiology and Pharmacology
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• 제3권4호
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• pp.383-391
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• 1999

This study was carried out to determine whether the effects of an ${\alpha}_2-adrenoceptor$ agonist, clonidine, on mean arterial pressure (MAP) and heart rate (HR) are influenced by mild hypothermia. Experiments were performed in respiration-controlled and spontaneously breathing pentobarbital-anesthetized rats. Rectal temperature was maintained at $37.5{\pm}0.3^{circ}C$ for normothermic groups or at $35.2{\pm}0.3^{circ}C$ for mild hypothermic groups. Intravenous injection of clonidine (1 and 2 ${\mu}g/kg)$ produced depressor and bradycardic responses in spontaneously breathing rats under both normothermic and mild hypothermic condition: a decrease in MAP was not altered but bradycardic response was significantly augmented in the mild hypothermic group as compared with the normothermic group. Under the respiration-controlled condition, the hypotensive effect of clonidine $(2\;{\mu}g/kg)$ was reduced, whereas the bradycardic effect was increased in mild hypothermic rats as compared with normothermic rats. Both hypotensive and bradycardic effects of clondine $(2\;{\mu}g/kg)$ were blocked by pretreatment with an ${\alpha}_2-adrenoceptor$ antagonist, yohimbine (0.5 mg/kg), in both thermal conditions. Yohimbine (0.5 mg/kg, i.v.) alone produced signifcantly an increase in heart rate in the mild hypothermic group than in the normothermic group. Pretreatment with a muscarinic receptor antagonist, atropine methylnitrate (1 mg/kg, i.v.), attenuated the bradycardic effect of clonidine in the mild hypothermic group but not in the normothermic group. These results suggest that clonidine- induced bradycardia is amplified by mild hypothermia probably through an increased parasympathetic activity.

• 약학회지
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• 제41권2호
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• pp.247-254
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• 1997

The proteinase-activated receptor (PAR-2) belongs to the family of seven transmembrane region receptors, like the thrombin receptor, it is activated by specific proteolytic clea vage of its extracellular amino terminus and a synthetic peptide (SLIGRL). The earthworm protein fraction (EPF) extracted from Lumbricus rubellus elicted dose- and endothelium-dependent relaxations in phenylephrine-contracted rat thoracic aorta, whereas heat inactivated EPF (0.5 ${\mu}g$ /ml) had no effect. In the presence of the nitric oxide synthase inhibitor NG-methyl-L-arginine (1.8 micro M), EPF (0.5 ${\mu}g$ /ml)-induced relaxations were partially inhibited. Furthermore, EPF (0.5 ${\mu}g$ /ml) dramatically caused relaxation of thrombin-desenstized rat thoracic aorta. These results indicate that EPF activates PAR-2 in vascular endothelial cell. Intravenous injection of EPF (20 mg/kg, bolus) into anesthetized rats produced a marked depressor response. EPF (0 ~ 80 ${\mu}g$ /ml, gradient) was very effective on increasing of perfusion volume in rabbit ear vessel preparations. These results imply the usefulness of EPF as a vascular smooth muscle relaxant and indicate that the activation of PAR-2 may be a mechanism of EPF on hemokinetic improvement.

• Natural Product Sciences
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• 제20권3호
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• pp.216-225
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• 2014

The present study was designed to investigate whether ethylacetate (EtOAc) fraction extracted from Rubus coreanum affect the contractility of the isolated thoracic aortic strips and blood pressure of normotensive rats. The EtOAc fraction ($400{\mu}g/mL$) significantly depressed both phenylephrine (PE, $10{\mu}M$)- and high $K^+$ (56 mM)-induced contractile responses of the isolated thoracic aortic strips in a concentration-dependent fashion. In the simultaneous presence of L-NAME (an inhibitor of NO synthase, $300{\mu}M$) and EtOAc ($400{\mu}g/mL$), both PE- and high $K^+$-induced contractile responses were recovered to the corresponding control level in comparison with inhibition of EtOAc-treatment alone. Moreover, in the simultaneous presence of EtOAc after pretreatment with 0.4% CHAPS, both PE- and high $K^+$-induced contractile responses were recovered to the corresponding control level compared to the inhibitory response of EtOAc-treatment alone. Also, in anesthetized rats, EtOAc fraction (0.3~3.0 mg/kg) injected into a femoral vein dose-dependently produced depressor responses. This hypotensive action of EtOAc fraction was greatly inhibited after treatment with phentolamine (1 mg/kg), chlorisondamine (1 mg/kg), L-NAME (3 mg/kg/30 min) or sodium nitroprusside ($30{\mu}g/kg/30 min$). Intravenous infusion of EtOAc fraction (1.0~10.0 mg/kg/30 min) markedly inhibited norepinehrine-induced pressor responses. Taken together, these results demostrate that EtOAc causes vascular relaxation in the isolated rat thoracic aortic strips as well as hypotensive action in anesthetized rats. These vasorelaxation and hypotension of EtOAc seem to be mediated at least by the increased NO production through the activation of NO synthase of vascular endothelium, and the inhibitory adrenergic modulation.