• Title/Summary/Keyword: Adrenal medulla

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Effect of Various Divalent Ions on the Calcium Current of Adrenal Medullary Chromaffin Cells in the Rat

  • Kim, Jun;Leem, Chae-Hun;Kim, Sang-Jeong
    • The Korean Journal of Physiology
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    • v.26 no.2
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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 $Cd^{2+}$.

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Antigen Nonspecific Death of Immature Thymocytes by Corticosteroids and TNF (스테로이드와 TNF에 의한 항원 비특이적 미성숙 흉선세포 사멸)

  • Oh, Keunhee;Surh, Charles D;Cho, Jaejin;Lee, Dong-Sup
    • IMMUNE NETWORK
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    • v.4 no.2
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    • pp.81-87
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    • 2004
  • Background: In the thymus, developing thymocytes continually interact with thymic epithelial cell components. Self MHC restriction of mature T cells are imposed in the thymus through interaction of immature double positive thymocytes and thymic cortical epithelial cells. The site of negative selection, however, is a matter of debate. Through systemic injection of anti-TCR antibody or antigenic peptides, investigators suggested that most of the negative selection occurs in the thymic cortex. But the requirements for negative selection, i.e cellular counterparts and costimulatory molecules are more available in the medulla or cortico-medullary junction rather than in the thymic cortex. Methods: The direct and indirect pathways of thymocyte death after systemic anti-TCR antibody injection were separated through several experimental systems. B6 mice were either adrenalectomized or sham-adrenalectomized to evaluate the role of endogenous glucocorticoids from adrenal gland. Role of TNF were evaluated through using TNF receptor double knockout mice. Results: We found that without indirectly acting mediators such as $TNF-\alpha$ or corticosteroid, double positive thymocyte death were minimal by systemic injection of anti-TCR antibody in TNF receptor double knockout neonatal mice. Also by analyzing neonatal wild-type mice with adoptively transferred mature T cells, only peripheral activation of mature T cells could induce extensive double positive thymocyte death. Conclusion: Thus, systemically injected anti-TCR antibody mediated thymocyte death are mostly induced through indirect pathway.

A Clinical Case Report On The Patient With Pheochromocytoma (갈색세포종 환자 1례의 임상증례(臨床證例) 보고)

  • Kim, Guk-Bum;Han, Jong-Hyun;Han, In-Sun;Kim, Eun-Gon;Lee, Jung-Hi;Kang, Beung-Chul;Seung, Kyung-Wha;Choi, Young-Kuy;Shim, Yun-Seub
    • The Journal of Internal Korean Medicine
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    • v.26 no.1
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    • pp.281-289
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    • 2005
  • Objective : Pheochromocytoma may arise within the adrenal medulla, or in other locations, where symptheic ganglia or chromaffin tissues are known to exist. Approximately 0.1 % of hypertensive patients have Pheochromocytoma, This study is to report the clinical effects of ShiHo-GuiZhiTang on pateints who have suffered from such symptoms of Pheochromocytoma as sweating, hypertention, Indigestion, anxiety neurosis, nausea, headache, and epigastric discomfort. Method : ShiHo-GuiZhiTang was used for a patient who had suffered from symptoms of Pheochromocytoma which was diagnosed as Banpeubanri-jueng of soyang disease in Sanghan-Ron. Result : In treating the patient with symptoms of Pheochromocytoma with ShiHo-GuiZhiTang, results were good. Conclusion : The results of this study suggest that ShiHo-GuiZhiTang is effective for such symptoms of Pheochromocytoma as sweating, hypertention, Indigestion, anxiety neurosis, nausea, headache, and epigastric discomfort.

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Dual control of the vestibulosympathetic reflex following hypotension in rats

  • Park, Sang Eon;Jin, Yuan-Zhe;Park, Byung Rim
    • The Korean Journal of Physiology and Pharmacology
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    • v.21 no.6
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    • pp.675-686
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    • 2017
  • Orthostatic hypotension (OH) is associated with symptoms including headache, dizziness, and syncope. The incidence of OH increases with age. Attenuation of the vestibulosympathetic reflex (VSR) is also associated with an increased incidence of OH. In order to understand the pathophysiology of OH, we investigated the physiological characteristics of the VSR in the disorder. We applied sodium nitroprusside (SNP) to conscious rats with sinoaortic denervation in order to induce hypotension. Expression of pERK in the intermediolateral cell column (IMC) of the T4~7 thoracic spinal regions, blood epinephrine levels, and blood pressure were evaluated following the administration of glutamate and/or SNP. SNP-induced hypotension led to increased pERK expression in the medial vestibular nucleus (MVN), rostral ventrolateral medullary nucleus (RVLM) and the IMC, as well as increased blood epinephrine levels. We co-administered either a glutamate receptor agonist or a glutamate receptor antagonist to the MVN or the RVLM. The administration of the glutamate receptor agonists, AMPA or NMDA, to the MVN or RVLM led to elevated blood pressure, increased pERK expression in the IMC, and increased blood epinephrine levels. Administration of the glutamate receptor antagonists, CNQX or MK801, to the MVN or RVLM attenuated the increased pERK expression and blood epinephrine levels caused by SNP-induced hypotension. These results suggest that two components of the pathway which maintains blood pressure are involved in the VSR induced by SNP. These are the neurogenic control of blood pressure via the RVLM and the humoral control of blood pressure via epinephrine release from the adrenal medulla.

THe Effect of Chronic Ehronic Treatment and Cold stress on Catecholaminergic Enzyme activity and mRNA in Rat Brain and Adrenals

  • Lee, Yong-Kyu;Park, Dong-H
    • Archives of Pharmacal Research
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    • v.19 no.5
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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.

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Studies on the Changes of Reproductive Organs, Serum Sex Hormones and Metabolites according to the Gestation Period in Rabbit (가토(家兎)의 임신(姙娠)에 따른 생식기관(生殖器官), 혈중(血中) 성(性)Hormone 및 대사물질(代謝物質)의 변화(變化)에 관(關)한 연구(硏究))

  • Lee, Kyu Seung;Han, Sung Wook;Park, Chang Sik
    • Korean Journal of Agricultural Science
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    • v.9 no.1
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    • pp.303-313
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    • 1982
  • The study was conducted to find out the concentrations of sex hormones and the contents of metabolites in serum, and the changes of weights and tissues on ovary, thyroid gland and adrenal gland according to gestation period in rabbit. The results were summarized as follows: 1. The ovary weights were increased significantly with the time e lapse after gestation and recovered normally at 5 days after parturition. In the histological changes of ovary, the lutein cells were hypertrophied and the secretory granules were increased actively until 3 weeks after gestation, and then a trophied thereafter. 2. The thyroid gland weights at all observation times were higher than those in control group, and the significance was recognized at 1, 3 and 4 weeks after gestation. The histological features of the secretory epithelium were the hyper trophic and columnar condition stimulating the functional state from 1 week after gestation. 3. The adrenal gland weights in experimental group were recognized significantly at 4 weeks after gestation, but showed higher than those in control group at all observation times. The zona fasciculata and zona reticularis of the gland showed the slight hypertrophic condition, but the zona glomeerulosa and adrenal medulla did not find out any particular changes. 4. The serum concentrations of progesterone and LH reached a peak level at 2 weeks and 1 week after geestation respectively, and rapidly began to decline thereafter. 5. The serum concentrations of estradiol-$17{\beta}$ and FSH were not detected below 20.0 pg/ml and 1.3 mIU/ml respectively. 6. The contents of total protein and non-protein nitrogen nitrogen were decreased gradually with the time elapse after gestation, but the significant differences were recognized from 3 weeks. 7. The total lipids were not changed markedly until 3 weeks, but increased significantly at 4 weeks after gestation and at 5 days after parturition. 8. The serum cholesterol tended to be decreased until 3 weeks, but increased at 4 weeks after gestation and at 5 days after parturition. 9. The serum calcium showed a continuous decrease during the gestation period, but the significant differences were recognized at 3 and 4 weeks. The serum phosphorus also had a significant decrease at 4 weeks after gestation.

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The influence of ginseng, reserpine, and chlorpromazine on epinephrine-induced and morphine induced hyperglycemiae (인삼(人蔘), reserpine, 및 chlorpromazine이 epinephrine 및 morphine 과혈당(過血糖)에 미치는 영향(影響))

  • Cheong, Dong-Kyun
    • The Korean Journal of Pharmacology
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    • v.1 no.1 s.1
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    • pp.17-36
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    • 1965
  • Besides it's all important analgesic action, morphine has, among others, hyperglycemic effect, though not important clinically, which is believed to be resulted from augmented glycogenolysis in the liver and muscles due to the increased liberation of epinephrine from the adrenal medulla upon the stimulation of the posterior part of hypothalamus. It is known that adrenergic blocking agents are acting inhibitory to this sort of hyperglycemia. Much, however, should as yet be studied for the drugs which affect central nervous system and release of endogenous catecholamine as far as their effects on hyperglycemia are concerned. Much is still not known about the effect of ginseng, which has been highly regarded in the Herb Medicine, as far as it's influence on the blood sugar is concerned. Author investigated the effects of chlorpromazine, reserpine and ginseng on epinephrine induced, and morphine-induced hyperglycemiae. Animals used in this experiment were healthy albino rabbits weighing approximately 2.0 kg of body weight and were all fasted for 24 hours, before the experiment undertaken. Blood sugar determination was carried out by Nelson-Somogy method. Results obtained are summarized as follows; 1. The groups of rabbits administered intravenously with epinephrine 0.02 mg/kg, and 0.05 mg/kg, showed marked and transient hyperglycemia within 15 minutes after injection. The maximal rate of elevation in blood sugar to the control level, were 28% and 57% respectively. The blood sugar returned to the control level within 3 hours. Thus, the hyperglycemic responses were paralleled with epinephrine doses. 2. The hyperglycemic responses by morphine were different according to the doses. The groups of rabbits in which 4 mg/kg of morphine was administered, did not show any hyperglycemic effect, but, in which 10 mg/kg of morphine administered, showed severe hyperglycemic effect, resulting in the maximal level within 2 hours after injection. The maximal rate of increasing in blood sugar ,level was 88%. Compared .with epinephrine-injected groups, morphjne-injected groups showed more persistent hyperglycemic effect, but returned to control blood sugar .level in 6 hours after injection. 3. The intravenous injection of chlorpromazine 2 mg/kg and 8 mg/kg evoked a slight, and persistent hyperglycemia. The maximal rate of increasing in blood sugar level were 15% and 23% respectively. These hyperglycemia gradually returned to the normal level in 5 or 6 hours after injection. Thus, the intensity of response was paralleled with the dose of chlorpromazine. 4. The intravenous injection of reserpine 0.2 mg/kg and 0.5mg/kg, showed the most persistent but steady elevation of blood sugar level in this experiments, resulting in the maximal level in 5 hours after injection. The maximal rate of increasing of blood sugar level were 18% and 39% respectively. 5. The blood sugar level from 24 hours to 30 hours after intraperitoneal administration of reserpine 1.0mg/kg, did not show statistically significant difference, compared with control groups. 6. The oral administration of ginseng extract 15 ml/kg did not. show any :change in blood sugar level. 7. The intravenous administration of epinephrine 0.05 mg/kg or morphine 4 mg/kg to the group pretreated with ginseng extract 15 ml/kg $20{\sim}30$ minutes before the experiment, evoked more marked hyperglycemic effect than the non-pretreated group. 8. The intravenous administration of epinephrine 0.02 mg/kg, morphine 4 mg/kg, or morphine 10 mg/kg to the groups pretreated with reserpine 0.2 mg/kg or 0.5 mg/kg $20{\sim}30$ minutes before experiment, produced more marked and persistent hyperglycemic effects than the groups injected with single epinephrine or morphine injection. 9. When epinephrine 0.05 mg/kg or morphine 10 mg/kg administered intravenously to the groups pretreated with the intraperitoneal administration of reserpine 1 mg/kg 24 hours before experiment morphine-induced hyperglycemia was inbibited, but epinephrine-induced hyperglycemia was augmented. 10. When epinephrine 0.05mg/kg or morphine 10 mg/kg administered intravenously to the groups pretreated with chlorpromazine, 2 mg/kg, 4 mg/kg, and 8 mg/kg $20{\sim}30$ minutes before the experiment, morphine-induced hyperglycemia was inbibited, but epinephrine-induced hyperglycemia was more persistent.

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