• Korean Journal of Veterinary Research
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• v.30 no.3
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• pp.277-281
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• 1990

Xylazine is commonly used for anesthesia in veterinary medicine and various adverse effects are developed. To examine if the severe hypotensive response associated with xylazine-induced anesthesia might be resulted from the stimulation of presynaptic alpha-2 adrenoceptors or the increase of vagal tone, effects of yohimbine, atropine and atropine with vagotomy on xylazine-induced severe and long-lasting hypotensive responses were investigated in rabbits. The results were summarized as follows: 1) Intravenously injected xylazine(1mg/kg)-induced hypotensive responses were inhibited by yohimbine(p<0.001). 2) Intravenously injected xylazine(1mg/kg)-induced hypotensive responses were not changed by atropine. 3) Intravenously administered xylazine(1mg/kg)-induced hypotensive responses are not changed by atropine with vagotomy. These results indicate that xylazine is thought to cause severe hypotensive response during anesthesia primarily by stimulating presynaptic alpha-2 adrenoceptors and other receptors or mechanisms may participate in the hgpotensive response of xylazine.

• Korean Journal of Pharmacognosy
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• v.9 no.1
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• pp.41-47
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• 1978

Total saponins and ether extracts of red and white ginseng were obtained and their effects on blood pressure in cat and their histamine liberating activities in rabbits were measured. 1) Ether extract of red ginseng showed a transient hypotensive effect and subsequently showed a remarkable and persistent hypotensive effect, whereas other three fractions, such as saponin fractions of red and white ginseng and ether extract of white ginseng showed only a initial transient hypotensive effects. 2) Histamine levels liberated into blood after administration of each fractions measured by the bioassay with guinea pig ileum. Ether extract of red ginseng immediately increased histamine contents in plasma but the histamine levels decreased to normal level within 10min in spite of decreased blood pressure was sustained. Although white ginseng saponin lowered blood pressure immediately when it is administered, histamine release was observed after 10min. The results suggest that hypotensive effects of ginseng seems to have no correlation with the histamine liberating activity. Ginseng appears to show hypotensive effect via some other mechanisms.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.213-223
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• 2008

Objectives : This study was performed to prove the hypotensive effect of 70% MeOH extracts from Scrophularia buergeriana (SB) on rat's femoral artery. Methods : We observed hypotensive effect of SB on rat's femoral artery. Scrophularia buergeriana Miquel, S. kakudensis, S. koraiensis and S. ningpoenesis Hemsl. were used by the RFLP method and sequence analysis of ITS regions, in order to compare and discriminate. Results : SB 70% MeOH Ex., Water fraction, 40% MeOH fraction, 100% MeOH fraction didn't show significantly hypotensive effect. 20% fraction of SB 70% MeOH Ex. showed significantly hypotensive effect. The size of ITS region on Scrophularia sp. is 589${\sim}$590bp and amount of G+C is 59.3% to 59.7%, and it showed the similar of ITS parts on Scrophularia sp. Conclusions : We concluded that SB Ex. have hypotensive activity, and it's more efficient when separated. And Scrophularia sp. showed the similar of DNA analysis.

• Korean Journal of Pharmacognosy
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• v.6 no.4
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• pp.211-217
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• 1975

The blood pressure response to Junci Herba water and methanol extracts in rabbit and $LD_{50}$ to Junci Herba water extract in mouse were investigated in order to develop a hypotensive agent from natural resources. $LD_{50}$ of Junci Herba water extract (WE) was 600 mg/kg in mouse, when WE was injected intraperitonealy. Junci Herba water and methanol extract, when injected into the vein of rabbit, produced a fall of blood pressure. Hypotensive effect of WE was suppressed by atropine and potentiated by phentolamine, while not affected by avil, propranolol, and phenoxybenzamine. Intravenous injection of chlorisondamine weakened the hypotensive effect of WE, and WE produced hypertensive effect in this rabbit. Intravenous injection of bretylium did not affect the hypotensive effect of WE, but WE produced hypertensive effect in this rabbit. In the rabbit treated with chlorisondamine, hypertensive effect of WE was suppressed by methysergide or bretylium, but not affected by atropine or phenoxybenzamine.

• The Journal of Korean Medicine
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• v.19 no.2
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• pp.50-58
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• 1998

The effects of the Evodiae fructus on the cardiovascular function were assessed in spontaneously hypertensive rats, and isolated preparation of spontaneously hypertensive rats aortic strip. In spontaneously hypertensive rats, intraperitoneal administration of methanol crude extract of Evodiae Fructus (0.5mg/kg) lowered aterial blood pressure which lasted for at least 4 hours. The hypotensive effect of Evodiae Fructus was more stronger with ${\alpha}-adrenoreceptor$ inhibitor(Phentholamine) and it was not affected by ${\beta}-adrenoreceptor$ inhibitor(Propranolol). The hypotensive effect of Evodiae Fructus was abolished by NAME. It is suggested that the hypotensive effect of Evodiae Fructus may be concern with endothelium-derived relaxing factor and it may be mediated through NO synthesis. Evodiae Fructus showed a vasorelaxing effect on denude aortic strip. It is suggested that Evodiae Fructus has a direct relaxing effect on vascular smooth muscle cells. Judging from above results, it was proved that hypotensive effect of Evodiae Fructus. The mechanism of hypotensive action may be concern with endothelium-derived relaxing factor and direct relaxing effect on vascular smooth muscle cells. Therefore, it is suggested that Evodiae Fructus is applicable to hypertension.

• The Korean Journal of Pharmacology
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• v.12 no.2 s.20
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• pp.61-65
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• 1976

Coptis rhizoma had been applied in the chines medicine as well as in the folk remidies and it was advocated that coptis rhizoma exerts good therapeutic effect in some case of alimentary disorders and other hypotensive ailments. However the basic pharmacology and the mechanism of hypotensive action are not clear. This experiment was carried out in order to reevaluate the pharmacology, especially hypotensive action of coptis rhizoma and to clarify the mechanism of action, in the rabbits and also $LD_{50}$ of coptis rhizoma was determined using mice as experimental animals. The results of the experiment were as follows. 1) $LD_{50}$ to the mice was 69 mg/kg. 2) Blood pressure manifested gradual responses by the fall of -17, -26, -62 mmHg in proportion to the administration of 3, 5, 10 mg/kg of coptis rhizoma extract respectively. 3) No significant differance was observed in heart rate between the normal control group and the coptis rhizoma extract treated group. 4) Administration of coptis rhizoma extract 5 mg/kg to the rabbit pretreated with atropine or avil did not show any significant difference in the blood pressure compared with that of control group. 5) In the rabbit pretreated with coptis rhizoma extract 5mg/kg, the hypotensive effect of epinephrine was significantly inhibited in comparison with that of normal rabbit.

• The Korean Journal of Pharmacology
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• v.15 no.1_2 s.25
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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.

• YAKHAK HOEJI
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• v.22 no.3
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• pp.163-174
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• 1978

Plantaginis seed has been applied in Chinese medicine a as well as in folk remedy. It was advocated that Plantaginis S Semeη exerts good therapeutic effects as anti-inflammatory, antitussive, obstipant and diuretic agent in some cases of alimentary, respiratory a and renal disorders. This study was carried out in order to r re-evaluate the pharmacological action, especially the hypotensive a action of Plantaginis Semen and to elucidate the mechanism of its a action, making use of Plantaginis Semen methanol extract (PME), because its basic pharmacological action, i. e., hypotensive action is n not clear. 1) PME, when administered into intravenous route, elicited the h hypotensive response dependent on the dose of PME given to the rabbit anesthetized with urethane. 2) This hypotensive response of P PME was inhibited by atropine and potentiated by physostigmine, but not influ$\varepsilon$need by vagotomization. 3) Depressor effect of PME was blocked by chlorisondamine, phentolamine, and bethanicline, while not altered by cyproheptadine, diphenhydramine and propran¬olol. 4) The secondary pressor response after blocking the depressor e effect of PME by chlorisondamine was produced, but this pressor response was deminished by atropine. 5) PME augmented the pressor e effect of norepinephrine and angiotensin, on the other hand, reduced b blood pressure elevated by carotid occlusion reflex. 6) These observa¬t tions suggest that PME may induce the hypotensive response via dual mechanisms of parasympathomimetic and sympatholytic action, that the positions of this action are cholinergic peripheral site and sympathetic ganglia respectively, and that PME may possess the pressor activity caused by stimulation of "atropine-sensitive site" which seems to existsin the sympathetic ganglia.

• Journal of Pharmaceutical Investigation
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• v.9 no.3
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• pp.27-38
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• 1979

This study was attempted to investigate the pharmacological action, especially depressor action of Phellodendri cortex and to elucidate the mechanism of its action, making use of Phellodendri cortex methanol extract (PCME) because its hypotensive action is not clear. Influence of PCME on the blood pressure of the rabbits and cats were observed in this study. PCME, when given intravenously in the rabbits and cats, elicited the hypotensive action, but intraventricular PCME in the rabbits did not show depressor action. Accumulation and tachyphylaxis by PCME administered into the ear-vein of the rabbits were not shown. Depressor effect of PCME in the rabbits was attenuated significantly by pretreatment with phentolamine, guanethidine, chorisondamine and atropine, but not by propranolol, diphenhydramine, cyproheptadine and vagotomization. The pressor activity of angiotensin was unimpaired after injection of maximal hypotensive doses (100mg/kg) of PCME, but the pressor activity of norepinephrine and carotid occlusion was abolished markedly. In addition, PCME given into jugular vein of the cats weakened norepinephrine pressor responses and caused the reversal of epinephrine pressor responses. These results suggest that the hypotensive action of PCME may be due to dual mechanisms by interference with peripheral sympathetic function, alpha adrenoceptor blocking action, and peripheral parasympathomimetics action, muscarinic action.

• Archives of Pharmacal Research
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• v.17 no.3
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• pp.145-149
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• 1994

Intravenous administration of hydro-methanolic extract of Cyperus scariosus (3-10 mg/kg) produced hypotensive and bradcardiac effects. These effects remianed unaltered in atropinized animals indicating that cardiovascular effects of the plant extract are not medliated through activation of muscarinic receptors. In the in vitro studies, it suppressed the spontaneous contractions of guinea-pig paired atria, rat ulterus and rabbit jejunum in a concentration-dependent (0.1-1 mg/ml) manner. It also inhibited histanmine or acetylcholine-induced contractions of guinea-pig ieum indicating non-sepcific spasmolytic action. In rabbit aorta, it inhibited norepinephrine $(10\;mu{M)}$ as well as $K^+$ (80mM)-induced contractions at similar concentrations (0.1-1 mg/ml). These data indicate that cyperus scariosus contains $Ca^{2+}$ channel blocker-like constituent(s) which may explain hypotensive effect observed in vivo and the general spasmolytic activity of plant explain its folkloric use in diarrhoea.