• The Korean Journal of Physiology
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• 제7권2호
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• pp.59-66
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• 1973

It has been reported that vasopressin disperse the melanophore granule of frog skin. The author used hypophysectomized and adrenergic receptor blockaded animals in order to define the mechanism of vasopressin on the melanopore pigment of frog skin. The Rana niglomaculata which could be found in the Seoul area were used on this experiment. The amount of the following drugs were injected into the lymphatic sac of the frog; vaospressin $(0.05\;{\mu}g/g\;B.W.)$, dibenzylin $(0.05\;{\mu}g/g\;B.W.)$, and propranolol $(0.01\;{\mu}g/g\;B.W.)$. The following results were observed; 1. Vasopressin dispersed the melanin granules of melanocyte of frog skin. 2. The melanin granule dispersion activity of vasopressin was observed on the hypophysectomized frog. 3. The melanin granule dispersion was observed on the adrenergic receptor blockaded frog with dibenzylin or propranolol respectively, especially the later one was found to be more obvious. 4. The melanin granule dispersion was observed on the frog which was injected with vasopressin after alpha-receptor or beta-receptor blockade and the later one was found to be more obvious. 5. The melanin granule dispersion was more effective with the blockade of beta-receptor after the treatment with vasopressin on hypophysectomized frog.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1997년도 춘계학술대회
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• pp.85-85
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• 1997

스트레스가 유발된 랫드의 대뇌에서 Vasopressin-catecholamine pathway의 활성도를 알아보기 위해 면역화학염색법으로 vasopressin 호르몬의 분비와 catecholamine의 생성변화를 tyrosine hydroxylase (TH) 효소의 발현변화로 규명하고, arginine vasopressin (AVP)과 V1 vasopressin receptor의 유전자 발현변화를 in situ hybridization 방법을 이용하여 살펴보았다. 수컷 SD rat를 7시간동안 stress cage에 넣어 16$\pm$1$^{\circ}C$의 물에 수침구속 스트레스를 준 후 대조군과 함께 관류고정하여 brain을 적출하였다. Brain의 hypothalamus 부위를 중심으로하여 동결절편하여 면역조직화학 염색과 in situ hybridization을 시행하였다. TH 면역조직화학 염색에서 대뇌의 줄무늬체 부위의 꼬리조가비핵에서와 시상하부 부위의 내측등쪽시상하부와 흑색질부위에서 스트레스군이 대조군에 비해 TH 면역염색성이 증가되어 관찰되었으나 시상하부 부위의 시삭위핵, 뇌실주위핵, 뇌실옆핵에서는 두 군간의 큰 면역염색성의 차이는 보이지 않았다. AVP 면역조직화학 염색에서는 시삭위핵에 많은 수의 AVP 양성 신경세포체들이 밀집되어 있으며 뇌실옆핵에서는 스트레스군에서 AVP 면역염색성이 약간 증가되어 관찰되었으나 신경섬유의 분포양상은 비슷하였다. 중간융기에서는 모두 강한 염색성의 신경섬유들이 관찰되어 두 군간에 큰 차이는 없었다. AVP 유전자에 대한 in situ hybridization 결과 시삭위핵의 신경세포에서 AVP mRNA 양성반응을 관찰할 수 있었으나 다른 시상하부핵에서는 관찰할 수 없었으며, V1 vasopressin receptor에 대한 in situ hybridization 결과는 두 군의 대뇌에서 모두 양성반응을 관찰할 수 없었으며 V1 vasopressin receptor 유전자의 조직별 발현정도와 스트레스에 의한 발현량 조절을 관찰할 필요가 있다고 사료된다.

• Archives of Pharmacal Research
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• 제26권1호
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• pp.64-69
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• 2003

To analyze vasopressin-induced $Ca^{2+}$ increase in liver cells, rat hepatocytes were isolated and attached to collagen-coated cover slips. Using fura-2, a $Ca^{2+}$-sensing dye, changes in intracellular $Ca^{2+}$ concentration by vasopressin were monitored. Results in this communication suggested that vasopressin-induced $Ca^{2+}$ increase were composed of both $Ca^{2+}$ release from internal $Ca^{2+}$ stores and influx from the plasma membrane. The $Ca^{2+}$ influx consisted of two distinguishable components. One was dependent on the presence of vasopressin and the other was not. SK＆F96365 blocked vasopressin-induced $Ca^{2+}$ influx in a dose-dependent manner. Vasopressin-induced $Ca^{2+}$ release from internal stores diminished in a primary culture of hepatocytes according to the culture time. However, changes in vasopressin-induced $Ca^{2+}$ influx across the plasma membrane differed from changes in the $Ca^{2+}$ release from internal stores, suggesting two separate signalings from receptor activation to internal stores and to the plasma membrane.

• The Korean Journal of Physiology and Pharmacology
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• 제22권2호
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• pp.173-182
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• 2018

Recent studies have provided several lines of evidence that peripheral administration of oxytocin induces analgesia in human and rodents. However, the exact underlying mechanism of analgesia still remains elusive. In the present study, we aimed to identify which receptor could mediate the analgesic effect of intraperitoneal injection of oxytocin and its cellular mechanisms in thermal pain behavior. We found that oxytocin-induced analgesia could be reversed by $d(CH_2)_5[Tyr(Me)^2,Dab^5]$ AVP, a vasopressin-1a (V1a) receptor antagonist, but not by $desGly-NH_2-d(CH_2)_5[D-Tyr^2,Thr^4]OVT$, an oxytocin receptor antagonist. Single cell RT-PCR analysis revealed that V1a receptor, compared to oxytocin, vasopressin-1b and vasopressin-2 receptors, was more profoundly expressed in dorsal root ganglion (DRG) neurons and the expression of V1a receptor was predominant in transient receptor potential vanilloid 1 (TRPV1)-expressing DRG neurons. Fura-2 based calcium imaging experiments showed that capsaicin-induced calcium transient was significantly inhibited by oxytocin and that such inhibition was reversed by V1a receptor antagonist. Additionally, whole cell patch clamp recording demonstrated that oxytocin significantly increased potassium conductance via V1a receptor in DRG neurons. Taken together, our findings suggest that analgesic effects produced by peripheral administration of oxytocin were attributable to the activation of V1a receptor, resulting in reduction of TRPV1 activity and enhancement of potassium conductance in DRG neurons.

• The Korean Journal of Physiology
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• 제27권2호
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• pp.217-225
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• 1993

The role of endogenous brain angiotensin ll (Ang ll) in mediating the cardiovascular and vasopressin responses to hemorrhage was assessed in conscious spontaneously hypertensive rats (SHR), and normotensive Wistar-Kyoto (WKY) rats. Artificial cerebrospinal fluid (aCSF) with or without losartan (DuP 753), a specific Ang ll receptor subtype I $(AT_1)$ antagonist and saralasin, a combined $AT_1/AT_2$ antagonist was administered into the cerebral lateral ventricle. Hemorrhage was performed at a rate of 3 ml/kg/min far 5 min. Intracerebroventricular administration of losartan and saralasin had no effect on the basal blood pressure. However, in response to acute hemorrhage, central Ang ll antagonists produced a remarkably greater fall in blood pressure, a reduced tachycardia, and an enhanced renin release compared with the aCSF control experiment in SHR, but effected no significant change in WKY rats. Central Ang ll-blocked SHR showed significantly lower blood pressure and heart rate during the recovery period than the aCSF control rats. Vasopressin release tallowing the hemorrhage was attenuated by icv Ang ll antagonists: the effect was more pronounced in SHR than in WKY rats. Centrally administered losartan and saralasin produced remarkably similar effects on the cardiovascular function and vasopressin responses to hemorrhage. These data suggest that brain Ang ll acting primarily through AT, receptors plays an important physiological role in mediating rapid cardiovascular regulation and vasopressin release in response to hemorrhage especially in Hypertensive rats.

• Childhood Kidney Diseases
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• 제24권2호
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• pp.126-130
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• 2020

Nephrogenic syndrome of inappropriate antidiuresis (NSIAD) is a rare X-linked genetic condition caused by a gain-of-function mutation of arginine vasopressin receptor 2 gene, AVPR2. We report the case of a male neonate diagnosed with NSIAD based on his DNA sequence of the AVPR2 gene and the clinical course. He demonstrated a complete correction of hyponatremia using oral urea. We suggest that (1) sequencing analysis of the AVPR2 gene ought to be done in newborns with prolonged euvolemic hyponatremia, hypo-osmolality, high urinary sodium and normal/low or undetectable AVP levels, and that (2) oral urea is a safe and effective treatment option in infants diagnosed with NSIAD until the patients are grown-up.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 공동 춘계학술대회
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• pp.80.2-80
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• 1999

No Abstract, See Full Text

• The Korean Journal of Physiology and Pharmacology
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• 제13권1호
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• pp.9-14
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• 2009

We cultured canine kidney(MDCK) cells stably expressing aquaporin-2(AQP2) on collagen-coated permeable membrane filters and examined the effect of extracellular ATP on arginine vasopressin(AVP)-stimulated fluid transport and cAMP production. Exposure of cell monolayers to basolateral AVP resulted in stimulation of apical to basolateral net fluid transport driven by osmotic gradient which was formed by addition of 500 mM mannitol to basolateral bathing solution. Pre-exposure of the basolateral surface of cell monolayers to ATP(100 ${\mu}M$) for 30 min significantly inhibited the AVP-stimulated net fluid transport. In these cells, AVP-stimulated cAMP production was suppressed as well. Profile of the effects of different nucleotides suggested that the $P2Y_2$ receptor is involved in the action of ATP. ATP inhibited the effect of isoproterenol as well, but not that of forskolin to stimulate cAMP production. The inhibitory effect of ATP on AVP-stimulated fluid movement was attenuated by a protein kinase C inhibitor, calphostin C or pertussis toxin. These results suggest that prolonged activation of the P2 receptors inhibits AVP-stimulated fluid transport and cAMP responses in AQP2 transfected MDCK cells. Depressed responsiveness of the adenylyl cyclase by PKC-mediated modification of the pertussis-toxin sensitive $G_i$ protein seems to be the underlyihng mechanism.

• 한국동물학회:학술대회논문집
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• 한국동물학회 1999년도 한국생물과학협회 학술발표대회
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• pp.255.1-255
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• 1999

No Abstract, See Full Text

• Clinical and Experimental Pediatrics
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• 제45권7호
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• pp.902-905
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• 2002

선천성 신성 요붕증은 일반적으로 성염색체 열성 유전 양식을 취하여 보인자인 어머니로부터 아들에게 유전되고, 발생 빈도는 드문 것으로 알려져 있으며, 항이뇨호르몬의 혈장 농도가 정상이거나 상승되어 있으면서도 신세뇨관이 항이뇨호르몬에 대한 저항성 때문에 요농축능 장애가 발생하여 다음과 다뇨를 특징으로 하는 질환으로 이뇨제와 프로스타글란딘 합성억제제의 사용이 치료의 근간을 이루어 왔다. 본 증례에서 발견된 AVPR2 수용체 유전자의 돌연변이 부위는 선천성 신성 요붕증의 표현형을 보이는 것으로 외국에서는 보고된 바 있으나 국내에서는 최초로 확인된 것이며, 고용량의 항이뇨 호르몬과 이뇨제 치료에 반응을 보였다.