• Applied Biological Chemistry
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• 제34권4호
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• pp.334-338
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• 1991

고상법으로 새로운 반응기구에 의한 bradykinin 및 $(D-Phe7\;-Leu^8)$ bradykinin을 합성하였다. Coupling은 N, N'-dicyclohexylcarbodiimide로 행하였으며 HBr 용액으로 cleavage한 후 조펩티드는 high pressure liquid chromatography로 정제하였다. 이들 펩티드의 순도는 paper chromatography, thin layer chromatography, paper electrophoresis, 융점측정기 및 아미노산기분석기에 의하여 분석하였다. Endopeptidase인 ${\alpha}-chymotrypsin$과 trysin, exopeptidase인 carboxypeptidase A와 leucine aminopeptidase를 사용하여 in vitro 상에서 이들 펩티드의 분해실험을 하였다. ${\alpha}-Chymotrypsine$ 및 carboxypeptidase A에 의하여 이들 펩티드는 빠르게 분해하였으나 leucine aminopeptidase는 N-말단의 2번 위치에 proline의 imino결합 때문에 분해하지 않았다.

• The Korean Journal of Physiology
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• 제29권2호
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• pp.233-241
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• 1995

The nonapeptide bradykinin has been shown to exhibit an array of biological activities including relaxation/contraction of various smooth muscles. In order to investigate the effects of bradykinin on the contractility and the electrical activity of antral circular muscle of guinea-pig stomach, the isometric contraction and membrane potential were recorded. Also, using standard patch clamp technique, the $Ca^{2+}-activated$ K currents were recorded to observe the change in cytosolic $Ca^{2+}$ concentration. $0.4 {\mu}M$ bradykinin induced a triphasic contractile response (transient contraction-transient relaxation-sustained contraction) and this response was unaffected by pretreatment with neural blockers (tetrodotoxin, atropine and guanethidine) or with apamin. Bradykinin induced hyperpolarization of resting membrane potential and enhanced the amplitude of slow waves and spike potentials. The enhancement of spike potentials was blocked by neural blockers. Both the bradykinin-induced contractions and changes in membrane potential were reversed by the selective $B_2$-receptor antagonist $(N{\alpha}-adamantaneacetyl-_{D}-Arg-[Hyp, Thy,_{D}-Phe]-bradykinin)$. In whole-cell patch clamp experiment, we held the membrane potential at -20 mV and spontaneous and transient changes of Ca-activated K currents were recorded. Bradykinin induced a large transient outward current, consistent with a calcium-releasing action of bradykinin front the intracellular calcium pool, because such change was blocked by pretreatment with caffeine. Bradykinin-induced contraction was also blocked by pretreatment with caffeine. From these results, it is suggested that bradykinin induces a calciumrelease and contraction through the $B_{2}$ receptor of guinea-pig gastric smooth muscle. Enhancement of slow wave activity is an indirect action of bradykinin through enteric nerve cells embedded in muscle strip.

• The Korean Journal of Physiology
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• 제26권1호
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• pp.69-74
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• 1992

Central cardiovascular effects of bradykinin were examined in anesthetized normotensive (NTR) and 2-kidney, 1 clip Goldblatt hypertensive rats (GHR). Bradykinin ($0.5{\sim}10nmol$) was administered into the right lateral cerebral ventricle, while blood pressure and heart rate (HR) were continuously monitored. In both NTR and GHR, intracerebroventricular bradykinin produced a dose dependent increase in mean arterial pressure (MAP) without significant changes in HR. GHR were more sensitive in the pressor response than NTR. The pressor response to bradykinin was attenuated by treatment with hexamethonium (2.5mg/kg/min, IV) or phentolamine (2mg/kg, IV) in both NTR and GHR. Reserpine treatment (2mg/kg/day, intramuscularly,2 days) did not affect the central pressor effect of bradykinin in NTR but it attenuated the pressor effect in GHR. Pretreatment with indomethacin (10mg/kg, intraperitoneally) or saralasin ($20{\mu}g$/kg/min, IV) was without effects on the pressor response to bradykinin. These results indicate that the central pressor effect of bradykinin is, at least in part, due to excitation of the autonomic nervous activity. Mechanisms other than the enhanced sympathetic nervous activity ran. not be ruled out, However. It is also suggested that the sensitivity to bradykinin is increased in the GHR.

• 대한약리학회지
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• 제2권1호
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• pp.17-20
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• 1966

The blood pressure responses following repeated injection of bradykinin were observed in the unanesthetized rabbits or rabbits treated with reserpine (0.5mg/kg IV) 24 hours previously. Bradykinin (0.5ug/kg) was injected intravenously at 10 minutes intervals for 5 times. In both groups of rabbits no appreciable changes in the depressor responses to each injection of bradykinin were observed. In the rabbits pretreated with reserpine, however, the more pronounced depressor responses to bradykinin was elicited.

• The Korean Journal of Physiology and Pharmacology
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• 제7권4호
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• pp.231-238
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• 2003

The present study was undertaken to investigate the effect of bradykinin on secretion of catecholamines (CA) evoked by stimulation of cholinergic receptors and membrane depolarization from the isolated perfused model of the rat adrenal glands, and to elucidate its mechanism of action. Bradykinin $(3{\times}10^{-8}M)$ alone produced a weak secretory response of the CA. however, the perfusion with bradykinin $(3{\times}10^{-8}M)$ into an adrenal vein of the rat adrenal gland for 90 min enhanced markedly the secretory responses of CA evoked by ACh $(5.32{\times}10^{-3}M)$, excess $K^+$ ($5.6{\times}10^{-2}M$, a membrane depolarizer), DMPP ($10^{-4}$ M, a selective neuronal nicotinic agonist) and McN-A-343 ($10^{-4}$ M, a selective M1-muscarinic agonist). Moreover, bradykinin ($3{\times}10^{-8}$ M) in to an adrenal vein for 90 min also augmented the CA release evoked by BAY-K-8644, an activator of the dihydropyridine L-type $Ca^{2+}$ channels. However, in the presence of $(N-Methyl-D-Phe^7)$-bradykinin trifluoroacetate salt $(3{\times}10^{-8}M)$, an antagonist of $BK_2$-bradykinin receptor, bradykinin no longer enhanced the CA secretion evoked by Ach and high potassium whereas the pretreatment with Lys-$(des-Arg^9,\;Leu^9)$-bradykinin trifluoroacetate salt $(3{\times}10^{-8}M)$, an antagonist of $BK_1$-bradykinin receptor did fail to affect them. Furthermore, the perfusion with bradykinin $(3{\times}10^{-6}M)$ into an adrenal vein of the rabbit adrenal gland for 90 min enhanced markedly the secretory responses of CA evoked by excess $K^+$ $(5.6{\times}10^{-2}M)$. Collectively, these experimental results suggest that bradykinin enhances the CA secretion from the rat adrenal medulla evoked by cholinergic stimulation (both nicotininc and muscarinic receptors) and membrane depolarization through the activation of $B_2$-bradykinin receptors, not through $B_1$-bradykinin receptors. This facilitatory effect of bradykinin seems to be associated to the increased $Ca^{2+}$ influx through the activation of the dihydropyridine L-type $Ca^{2+}$ channels.

• The Korean Journal of Physiology
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• 제28권2호
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• pp.191-196
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• 1994

Captopril, an inhibitor of angiotensin converting enzyme, is also known to inhibit the degradation of bradykinin. We examined the effects of intracerebroventricular (ICV) captopril on the central pressor response to bradykinin in normotensive, 2-kidney, 1 clip Goldblatt (GHR) and deoxycorticosterone acetate (DOCA)-salt hypertensive rats. Captopril (1 mg) and bradykinin (5 nmol) were administered into the right lateral cerebral ventricle, and blood pressure and heart rate were continuously monitored throughout the experiment. ICV captopril alone did not affect the blood pressure within 10 minutes but it significantly augmented the central pressor response to bradykinin in GHR. On the contrary, captopril was without effect on the pressor response to bradykinin in normotensive and DOCA-salt rats. These findings indicate that endogenous kinins are not critical in regulating arterial pressure in normotensive and DOCA hypertensive rats. However, in GHR, an enhanced activity of the brain kallikrein-kinin system in maintaining the high blood pressure is suggested.

• 약학회지
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• 제38권5호
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• pp.602-607
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• 1994

Based upon the previous experiments showing that kidney and lung tissues of rat had relatively abundant bradykinin binding sites, we tried to characterize and determine the densities of the bradykinin binding sites in the rabbit kidney tissue and proximal tubular cells under different growing conditions. Among the kidney tissue renal medulla segments showed the highest bradykinin binding sites. To determine which growth factors are to add in the serum free culture medium to express selectively the bradykinin binding sites in the rabbit kidney proximal tubular cells, we tried so called hormone-deletion approach and in here insulin, hydrocortisone, transferrin, triiodothyronine and prostaglandin $E_1$ are examined. By performing receptor binding assay and determination of protein concentrations, we may conclude that the most required hormones in the expression for bradykinin binding sites are insulin and transferrin, and fetal bovine serum is shown to be less effective in this regard.

• Journal of Acupuncture Research
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• 제24권2호
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• pp.39-49
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• 2007

목적 : 봉독으로 유발된 통각수용의 강도와 봉독으로 나타나는 항통각수용(통각억제성)의 강도를 쥐의 포르말린 테스트를 통해 상호관련됨을 확인하고 capsaicin과 bradykinin으로 통증 유발된 쥐의 자발적인 통증행동(핥기횟수측정; LN), 꼬리경타시험(TFL)과 열판시험(HPL)을 통해 봉독의 항통각수용(통각억제)작용을 재확인 하고자 하였다. 방법 : 쥐의 뒷다리에 통증유도 물질인 Capsaicin 또는 Bradykinin을 20${\mu}l$를 주사하여 동통을 유발하고 자발적 통증행동인 핥기횟수측정(LN), 꼬리경타기간(TFL)과 열판 위에서의 온도자극에 쥐가 반응하는 시간을 측정(HPL)하는 실험을 봉독을 주입하거나, 몰핀을 주입하거나, 아무것도 주입하지 않고 통증유발만 시킨 이후에 각각 시행하였다. 결과: 1. Capsaicin 또는 Bradykinin으로 동통유발 후 LN은 두드러증가를 보임, HPL은 감소를 TFL은 두드러진 감소를 나타내었다. 2. 봉독이나 몰핀 주입 30분 후에 Capsaicin으로 동통유발 이후 LN은 봉독과 몰핀에서 모두 현격한 감소를, HPL은 봉침은 현격한 증가를, 몰핀에서는 감소를, TFL은 봉침과 몰핀에서 모두 현격한 증가를 나타내었다. 3 봉독과 몰핀주입 30분후에 Bradykinin으로 동통유발 이후 LN은 봉독은 증가 몰핀은 현격한 감소를, HPL은 봉침은 증가 몰핀에서는 현격한 증가를, TFL은 봉침과 볼핀에서 모두 증가를 나타내었다. 결론 : 봉독은 Capsaicin 또는 Bradykinin으로 동통유발된 통각수용행동을 감소시키는 결과를 나타내었는데 이것은 기존의 연구결과들에서의 봉독의 항통각수용(통각억제성)의 효과를 입증하였고 봉약침은 염증의 개선이나 암과 관련된 동통에 유효한 방법임을 시사하는 것이다.

• 통합자연과학논문집
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• 제10권2호
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• pp.74-77
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• 2017

Bradykinin receptor B2 (B2R) is a GPCR protein which binds with the inflammatory mediator hormone bradkynin. Kallidin, a decapeptide, also signals through this receptor. B2R is crucial in the cross-talk between renin-angiotensin system (RAS) and the kinin-kallikrein system (KKS) and in many processes including vasodilation, edema, smooth muscle spasm and pain fiber stimulation. Thus the structural study of the receptor becomes important. We have predicted the peptide structures of Bradykinin and Kallidin from their amino acid sequences and the structures were docked with the receptor structure. The results obtained from protein-protein docking could be helpful in studying the B2R structural features and in the pathophysiology in various diseases related to it.

• 대한약리학회지
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• 제8권1호
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• pp.63-65
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• 1972

It is well known that pharmacological actions of bradykinin are smooth muscle dilatation, increase in capillary permeability, accumulation and migration of leucocytes and inducement of pain. The most significant action of bradykinin is the dilatation of blood vessels. The responses of bradykinin (0.5ug/kg, i. v. injection) on blood pressure were observed before and after single i. v. administration of guanethidine (2mg/kg) in the rabbits. The result of experiment was as follows: In the rabbit pretreated with guanethidine, the depressor response of bradykinin was much pronounced in comparison with that of normal rabbit.