• 인지과학
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• 제1권2호
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• pp.361-376
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• 1989

카테콜아민 생합성에 관여하는 마지막 효소인 phenylethanolamine Nmethyltransferase는 norepinephrine 을 epinephrine으로 전환시키는 중요한 효소이다. PNMT효소의 발현은 epinephrine 신경세표의 발현에 필수적이다.따라서 PNMT 유전자를 크로닝하여 그 구조를 결정하고,유전자 발현연구를 하는 것은 상당히 중요한 일이다.그러나 최근에 저자가 bovine 및 human cDA 를 처음으로 분리하여 그 구조를 보고한 것 외에는 아직까지 인간과 백서 전체 genomic DNA 의 분리 보고는 없다.이에 저자들은 인간과 백서 PNMT유전자의 전체구조와 여러종(species)사이의 진화적인 관계를 규명하기 위해서 human 과 Rat genomic library 를 만들고,이 library 를 이용하여 bovine cDNA 를 probe로 13.1kb와 13.2kb길이의 인간과 백서의 genomic clone 을 분리 크리닝하는데 성공하여 유전자의 구조적 규명하였다.

• Biomolecules & Therapeutics
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• 제3권1호
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• pp.21-27
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• 1995

The only compounds with antagonistic activity via AT$_1$receptor, one of two subtypes of angiotensin II (AII) receptor, have been demonstrated to block the vasoconstriction effects of AII and thereby provide therapeutic potential. This initiated the search for compounds with high specific affinity to AT$_1$receptor and their effective screening methods. The radioligand binding assay for the AII receptor is regarded as the primary method for the evaluation of AT$_1$receptor antagonists for their activity. In this paper, we characterized the liver AT$_1$receptor and describe the efficient method of the radioligand binding assay using rat liver as a source of AT$_1$receptor. Equilibrium binding studies with rat adrenal cortex, adrenal medulla, liver and bovine adrenal showed that the specific bindings of [$^3$H] AII were saturable in all tissues and the Scatchard plots of those data were linear, suggesting a single population of binding sites. Hill slopes were very near to the unity in all tissues. Kinetic studies of [$^3$H) AII binding in rat liver homogenates yielded two association rate constants, 4.10$\times$10$^{7}$ M$^{-1}$ min$^{-1}$ and 4.02$\times$10$^{9}$ M$^{-1}$ min$^{-1}$ , with a single dissociation rate constant, 7.07$\times$10$^{-3}$ min-$^{-1}$ , possibly due to the partial dissociation phenomenon. The rank order of inhibition potencies of [$^3$H] AII binding in rat liver was AII>Sarile>Losartan>PD 123177. Rat liver homogenates revealed to have very high density of homogeneous population of the AT$_1$receptor subtype, as the specifically bound [$^3$H] AII was not inhibited by PD 123177, the nonpeptide antagonist of AT$_2$. The results of this study demonstrated that the liver homogenates from rats could be the best receptor preparation for the AT$_1$receptor binding assay and provide an efficient system for the screening of newly synthesized candidate compounds of AT$_1$receptor antagonist.

• The Korean Journal of Physiology
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• 제26권2호
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• pp.113-122
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• 1992

It is well known that chromaffin cells of adrenal medulla secrete catecholamine in response to sympathetic nerve activation and the influx of $Ca^{2+}$ through the voltage dependent $Ca^{2+}$ channels (VDCC) in the cell membrane do a major role in this secretory process. In this study, we explored the effect of divalent cations on VDCC of rat chromaffin cells. Rat (Sprague-Dawley rat, 150-250 gm) chromaffin cells were isolated and cultured. Standard giga seal, whole cell recording techniques were employed to study $Ca^{2+}$ current with external and internal solutions that could effectively isolate VDCC currents $(NMG\;in\;external\;and\;TEA\;and\;Cs^{2+}\;in\;internal\;solution)$. The voltage dependence and the inactivation time course of VDCC in our cells were identical to those of bovine chromaffin cells. A persistent inward current was first activated by depolarizing step pulse from the holding potential (H.P.) of -80 mV to -40 mV, increased to maximum amplitude at around +10 mV, and became smaller with progressively higher depolarizing pulses to reverse at around +60 mV. The inactivation time constant $(\tau)$, fitted from the long duration test potential (2 sec) was $1295.2{\pm}126.8$ msec $(n=20,\;1\;day\;of\;culture,\;mean\;{\pm}S.E.M.)$ and the kinetic parameters were not altered along the culture duration. Nicardipine $(10\;{\mu}M)$ blocked the current almost completely. Among treated divalent cations such as $Cd^{2+},\;Co^{2+},\;Ni^{2+},\;Zn^{2+}\;and\;,Mn^{2+},\;Cd^{2+}$ was the most potent blocker on VDCC. When the depolarizing step pulse from -80 mV to 10 mV was applied, the equilibrium dissociation constant $(K_d)$ of $Cd^{2+}\;was\;39\;{\mu}M,\;K_d\;of\;Co^{2+}\;was\;100\;{\mu}M\;and\;K_d\;of\;Ni^{2+}];was];780{\mu}M.$ The principal findings of this study are as follows. First, the majority of $Ca^{2+}$ channels in rat chromaffin cells are well classified to L-type $Ca^{2+}$ channel in the view of kinetics and pharmacology. Second, all divalent cations tested could block the $Ca^{2+}$ current and the most potent blocker among the tested was $Cd^{2+}$.

• 한국가축번식학회지
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• 제4권1호
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• pp.35-45
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• 1980

The purpose of this experiment was to investigate the effects of castration and administration of testosterone propionate(TP) on the development of the thyroid, adrenal glands and the testis in immature male rats, 25 days immatured, weighing 64.1${\pm}$2g, were divided into two groups of control and castrated, each sub-divided into 30 rats again, treated and untreated with TP respectivity. Each rat was given 20$m\ell$ of TP subcutaneously at two weeks interval. Six rats among each group were randomly sacrificed at 7, 21, 35, 49, and 63 days after treatment, of which their thyroid, adrenal glands and testis were collected for cytometric observation. The results obtained were as follows. 1. The size of the follicle of thyroid glands had a tendency to increase proportionally to the treatment period in every group. However, in castration group, the follicular size of the untreated with TP were significantly increased from 49 days (p<0.05) after treatment than that of the treated with TP, while in control group, the treated with TP were not increased during the treatment period. Regarding the height of the follicular epithelial cell in thyroid gland, the treated with TP had a tendency to increase than the untreated with TP in both castration and control group. 2. Regarding the size of the follicle of thyroid gland in relation with the increment period, the untreated with TP in control group were slightly increased from 49 days after treatment, but the treated with TP were not changed significantly. Castration group had a tendency to increase significantly than the control group, especially the untreated with TP in castration group were significantly increased. 3. As for the change of the relative height of thyroidal follicular epithelial cell in relation with the increment of treatment period, the untreated, A and C group, in both castration and control group were increased at 35 days 63 days after treatment while the treated, B and D group had tendency to increase from 21 days after treatment. 4. Regarding the thickness fo adrenal cortex, the castration group had a tendency to increase than the control group until 21 days after treatment. But, at 35 days, the change of the thickness was reversed; Mean while at 49 days and 63 days, especially C group in castration were significantly increased than any other groups although there were no significant differences among the every group during the whole treatment period. Regarding the thickness of adrenal cortex in relation with the increment of treatment period, A, B and C group had a tendency to increase until 21 days after treatment. After that period, there was no significant increment in all groups. Especially, in D group, there were no significant changes from 7 days to 63 days after treatment. 5. As for the tickness of adrenal medulla, there were no significant changes in every group of castration and TP treatment, except that the castration group had a tendency to increase continually than the control throughout the whole treament period. 6. In terms of the number, diameter and thickness of seminiferous tubule in testis of control group, the treated group with TP were distinctly reduced than those of the untreated group from 49 days after treatment respectively.

• 치위생과학회지
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• 제14권2호
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• pp.240-247
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• 2014

본 연구에서는 formalin으로 유발된 악안면 염증성 통증모델에서 acaiberry의 진통작용과 항산화작용을 확인하고자 하였다. 실험동물의 악안면 통증은 수염부에 5% formalin ($50{\mu}l$)을 주입하여 유발하였고 45분간 행위반응을 측정하였다. Acaiberry의 통증행위반응 조절효과를 확인하기 위해 formalin 주입 30분 전 실험동물에게 복강투여 하였다. Acaiberry의 통증행위반응조절에 대한 생리적 기전을 확인하기 위해 항염증과 항산화의 지표인 p38 MAPK의 활성 및 NOX4의 발현을 단백정량분석법을 통해 평가하였다. Acaiberry (16, 80, 160 mg/kg)의 복강투여는 실험동물의 통증행위반응을 대조군($290{\pm}17.4$)에 비해 농도 의존적($205.3{\pm}21.8$, $137.8{\pm}21.8$, $53.5{\pm}30.2$)으로 감소시켰다. 이러한 통증행위반응은 시간의 경과에 따라 변화를 나타내었다. Formalin의 주입으로 인한 통증행위반응은 15분 이후부터 증가하여 25분, 30분에 가장 높게 나타났으며 40분까지 지속되다가 45분에 감소되었으며, 15~40분에서 증가되었던 통증행위반응은 acaiberry의 복강투여로 인해 현저하게 감소되었다. 또한 acaiberry의 복강투여는 실험동물의 연수와 부신에서 p38 MAPK활성 및 NOX4의 발현을 감소시켰다. Acaiberry은 포르말린으로 유도한 악안면 통증에서 실험동물의 통증행위반응을 유의하게 감소시켰으며, 이는 p38 MAPK 및 NOX4 경로의 조절을 통한 항염증 및 항산화 작용에 의한 것으로 사료된다.

• Archives of Pharmacal Research
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• 제19권5호
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• pp.374-380
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• 1996

Sprague-Dawley male rats (150 g) were chronically treated with 5 v/v % ethanol admixed with nutritionally complete liquid diet and fed ad libitum for 3 weeks. One half of each group was exposed to cold stress at 4 ^{\circ}C either for 24 h (for determination of mRNA by in situ hybridization) or for 48 h (for determination of enzyme activity). Chronic ethanol treatment (ethanol) did not affect tyrosine hydroxylase(TH) mRNA level in locus coeruleus(LC) of brain and adrenal medulla(AM) compared to controls. Cold stress showed strong increase of TH mRNA level in LC and AM compared to controls. Pretreated ethanol reduced the increased TH mRNA level by cold stress in LC and AM. Ethanol did not affect TH activity in LC and adenal glands(adrenals). Cold stress increased TH activity in LC but not in adrenals. Pretreated ethanol did not reduce the increased TH activity by cold stress in LC but this result was not shown in adrenals. Phenylethanolamine-N-methyltransferase(PNMT) activity in $C_{1}$$C_{2}$ and adrenals increased only in ethanol treated group. THese results suggest that ethanol does not affect TH mRNA level and activity in LC and adrenals, but increases PNMT activity in $C_{1}$$C_{2}$ and adrenals in normal rat. It is also suggested that pretreated ethanol reduces the magnitude of cold stress response, that is induction of TH mRNA in LC and AM, and does not reduce the protein activation of TH that is also cold stress response in LC.