• 제목/요약/키워드: proximal tubule cells

검색결과 64건 처리시간 0.021초

복합 Vitamin 과양투여로 인한 신근위곡세요관 상피세포의 미세구조변화 (Electron Microscopic Study on the Changes of the Epithelial Cells of Proximal Convolted Tubule due to Overdosage of Vitamin Complex)

  • 홍순덕;장인호
    • 한국미생물·생명공학회지
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    • 제5권4호
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    • pp.185-189
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    • 1977
  • 성숙자계에 과양의 vitamin A, D 및 E를 투여하고 신근위파세요관상피세포에 야기되는 징세구조의 변화를 관찰한바 그 결과를 요약하면 다음과 같다. 1일 2.5ml의 기준량을 투여한 군에서는 mitochondria의 경한 여진 및 rER에서 ribosome의 경광의 탈낙이 있으며, 7.5ml 투여군에서는 세포의 종완이 좀더 심해저서 기질이 넓어져 보였고 mitochondria는 중등도의 여창을, 곳에 따라서는 서로 융합한 chondriosphere의 형성도 볼수 있었다. 12.5ml 투여군에세는 상기한 소견들이 더욱 심하여지는 경향이였다. 이상의 연구결과로보아 vitamin 과양투여에 의한 순근위암세요관상피세포의 변화는 세포고복을 주로하는 경징한 가역적변화로서 성계에 대한 vitamin 과양투여는 신근위곡세요관상피세포에 큰 영향을 주지 않는것으로 사요된다.

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Tumor necrosis factor α-converting enzyme inhibitor attenuates lipopolysaccharide-induced reactive oxygen species and mitogen-activated protein kinase expression in human renal proximal tubule epithelial cells

  • Bae, Eun Hui;Kim, In Jin;Choi, Hong Sang;Kim, Ha Yeon;Kim, Chang Seong;Ma, Seong Kwon;Kim, In S.;Kim, Soo Wan
    • The Korean Journal of Physiology and Pharmacology
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    • 제22권2호
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    • pp.135-143
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    • 2018
  • Tumor necrosis $factor-{\alpha}$ ($TNF{\alpha}$) and the angiotensin system are involved in inflammatory diseases and may contribute to acute kidney injury. We investigated the mechanisms by which $TNF{\alpha}$-converting enzyme (TACE) contributes to lipopolysaccharide (LPS)-induced renal inflammation and the effect of TACE inhibitor treatment on LPS-induced cellular injury in human renal proximal tubule epithelial (HK-2) cells. Mice were treated with LPS (10 mg/kg, i.p.) and HK-2 cells were cultured with or without LPS ($10{\mu}g/ml$) in the presence or absence of a type 1 TACE inhibitor ($1{\mu}M$) or type 2 TACE inhibitor ($10{\mu}M$). LPS treatment induced increased serum creatinine, $TNF{\alpha}$, and urinary neutrophil gelatinase-associated lipocalin. Angiotensin II type 1 receptor, mitogen activated protein kinase (MAPK), and TACE increased, while angiotensin-converting enzyme-2 (ACE2) expression decreased in LPS-induced acute kidney injury and LPS-treated HK-2 cells. LPS induced reactive oxygen species and the down-regulation of ACE2, and these responses were prevented by TACE inhibitors in HK-2 cells. TACE inhibitors increased cell viability in LPS-treated HK-2 cells and attenuated oxidative stress and inflammatory cytokines. Our findings indicate that LPS activates renin angiotensin system components via the activation of TACE. Furthermore, inhibitors of TACE are potential therapeutic agents for kidney injury.

Reabsorption of Neutral Amino Acids Mediated by Amino Acid Transporter LAT2 and TAT1 in The Basolateral Membrane of Proximal Tubule

  • Park Sun Young;Kim Jong-Keun;Kim In Jin;Choi Bong Kyu;Jung Kyu Yong;Lee Seoul;Park Kyung Jin;Chairoungdua Arthit;Kanai Yoshikatsu;Endou Hitoshi;Kim Do Kyung
    • Archives of Pharmacal Research
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    • 제28권4호
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    • pp.421-432
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    • 2005
  • In order to understand the renal reabsorption mechanism of neutral amino acids via amino acid transporters, we have isolated human L-type amino acid transporter 2 (hLAT2) and human T-type amino acid transporter 1 (hTAT1) in human, then, we have examined and compared the gene structures, the functional characterizations and the localization in human kidney. Northern blot analysis showed that hLAT2 mRNA was expressed at high levels in the heart, brain, placenta, kidney, spleen, prostate, testis, ovary, lymph node and the fetal liver. The hTAT1 mRNA was detected at high levels in the heart, placenta, liver, skeletal muscle, kidney, pancreas, spleen, thymus and prostate. Immunohistochemical analysis on the human kidney revealed that the hLAT2 and hTAT1 proteins coexist in the basolateral membrane of the renal proximal tubules. The hLAT2 transports all neutral amino acids and hTAT1 transports aromatic amino acids. The basolateral location of the hLAT2 and hTAT1 proteins in the renal proximal tubule as well as the amino acid transport activity of hLAT2 and hTAT1 suggests that these transporters contribute to the renal reabsorption of neutral and aromatic amino acids in the basolateral domain of epithelial proximal tubule cells, respectively. Therefore, LAT2 and TAT1 play essential roles in the reabsorption of neutral amino acids from the epithelial cells to the blood stream in the kidney. Because LAT2 and TAT1 are essential to the efficient absorption of neutral amino acids from the kidney, their defects might be involved in the pathogenesis of disorders caused by a disruption in amino acid absorption such as blue diaper syndrome.

초대배양된 토끼 신장 근위세뇨관세포의 성장과 기능분화에 대한 insulin과 IGF의 효과 - Na+ uptake에 대한 IGF-I의 효과 - (Effects of insulin and IGF on growth and functional differentiation in primary cultured rabbit kidney proximal tubule cells - Effects of IGF-I on Na+ uptake -)

  • 한호재;박권무;이장헌;양일석
    • 대한수의학회지
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    • 제36권4호
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    • pp.783-794
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    • 1996
  • 이온운반계는 생체의 각기 다른 세포의 성장을 조절하는 성장조절인자들의 효과를 매개하는데 깊은 관련이 있는 것으로 보고되고 있다. 신장 근위세뇨관에서 솔변 연 $Na^+/H^+$ 상호운반계는 사구체에서 여과된 나트륨의 재흡수와 수소이온의 분비를 조절하는 중요한 기능을 수행한다. 이 연구는 초대배양된 신장 근위세뇨관세포의 나트륨 운반을 Insulin-like Growth Factor-I(IGF-I)이 어떤 경로를 통하여 조절하는지를 알아보고자 실시하였다. 결과는 아래와 같다. 1. 초대배양된 신장 근위세뇨관세포에서 $Na^+$ uptake는 시간의존적으로 증가되었으며, 30분동안 $Na^+$ uptake를 실시한 결과 세포외 NaCl 농도의존적으로 $Na^+$ uptake를 유의성있게 감소시켰다(대조군; $40.11{\pm}1.76$, 140mM군; $17.82{\pm}0.94pmole\;Na^+/mg\;protein/min$). 2. $Na^+$ uptake는 iodoacetic acid(IAA, $1{\times}10^{-4}M$) 또는 valinomycin($5{\times}10^{-6}M$)처리시 대조군에 비해 각각 $50.51{\pm}4.4%$$57.65{\pm}2.27%$ 억제되었으며, ouabain($5{\times}10^{-5}M$)을 처리한 경우는 $140.23{\pm}3.37%$ 증가되었다. IGF-I($1{\times}10^{-5}M$)으로 배양한 세포를 actinomycin D($1{\times}10^{-7}M$)와 cycloheximide($4{\times}10^{-5}M$)로 처리시 $Na^+$ uptake는 대조군에 비해 각각 $90.21{\pm}2.39%$$89.64{\pm}3.69%$로 감소되었다. 3. IGF-I으로 배양한 세포에서 세포외 cAMP는 농도의존적($10^{-8}-10^{-4}M$)으로 $Na^+$ uptake를 유의성있게 감소시켰고, 3-isobutyl-1-methyl-xanthine(IBMX, $5{\times}10^{-5}M$)도 억제시켰다. Pertussis toxin(PTX, 50pg/ml)이나 cholera toxin(CTX, $1{\mu}g/ml$)의 처리시에도 $Na^+$ uptake는 억제되었다. 세포외 phorbol 12-myristate 13 acetate(PMA) 또한 농도의존적(1-100ng/ml)으로 $Na^+$ uptake를 감소시켰다. 그러나 staurosporine($1{\times}10^{-7}M$)은 $Na^+$ uptake에 영향을 미치지 않았으며 PMA와 stauiosporine을 동시에 처리했을 때도 $Na^+$ uptake는 억제되지 않았다. 결론적으로 초대배양된 토끼 신장 근위세뇨관세포에서 $Na^+$ uptake는 막전위와 세포내 에너지 의존적이며 IGF-I은 부분적으로 단백질 및 RNA 합성을 통해서 그리고 세포내 cAMP나 PKC 경로를 통해서 $Na^+$ uptake를 조절하는 것으로 생각된다.

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백서(白鼠) 편측(片側) 신장절제(腎臟切除) 후(後) 좌신(左腎)과 우신(右腎)의 조직학적(組織學的) 및 전자현미경적(電子顯微鏡的) 관찰(觀察)과 형태계측학적(形態計測學的) 비교(比較) 연구(硏究) (Morphometrical, Histological and Electron Microscopical Comparison of Left and Right Kidney in Uninephrectomized Rat)

  • 이경태;송춘호
    • Journal of Acupuncture Research
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    • 제15권2호
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    • pp.43-60
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    • 1998
  • This study examined the histomorphomeric and histological changes of the left and right kidney in uninephrectomized rat. The results were as follows: 1. In the control, the right kidney was more prominent than the left in the basement membrane of glomerular capillaries. The podocyte had well developed Golgi apparatus in the left kidney and rough endoplasmic reticulum in the right kidney. 2. At the 30 days after unilateral nephrectomy, the basal lamina of glomerular capillaries was prominently thickened in the right kidney. The cytoplasm of the podocyte of the left kidney was markedly increased and had free ribosomes, developed Golgi apparatus and rough endoplasmic reticulum. 3. At the 30 days, the section of the glomeruli were more enlarged in the left kidney than in the right. 4. At the 20 day, the nuclear section of the podocytes were markedly enlarged in the right kidney, but those of the left kidney were diminished. The mitochondrial section of the podocytes were prominently increased in the right kidney. 5. The nuclear section of the parietal layer lining cells was no significant change in the right kidney. That of the left kidney was increased at the 20 days and decreased at the 40 days. The nuclear section of glomerular endothelium of the left kidney increased earlier than the right. 6. In the morphometry of the control kidney, the section areas, long and short diameters, the nuclear section, the mitochondrial section of the proximal tubule cells, and the changes of those were more large in the right kidney than in the left. 7. The luminal secretory vesicles and peroxisomes of the left kidney were more than the right at the 20 days. The increase of mitochodrial section in the proximal tubule cells of the left kidney was more prominent than the right. The large cytoplasmic vacuoles were more prominent in the left kidney than in the right. 8. The thickness of cytoplasm and brush border was more thick in the control left kidney than in the control right. The change of cytoplasmic thickness of the left kidney was increased earlier than in the right and both kineys were increased in the thickness of brush border at the 30 days.

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DIVERGENT ROLES OF A NOVEL PHOSPHOLIPASE $A_2$ IN CELL DEATH

  • Schnellmann, Rick G.
    • 한국독성학회:학술대회논문집
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    • 한국독성학회 2002년도 Molecular and Cellular Response to Toxic Substances
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    • pp.68-88
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    • 2002
  • Phospholipase A$_2$ (s) are esterases that hydrolyze the sn-2 ester bond in phospholipids, releasing a fatty acid and a lysophospholipid. We previously showed that most PLA$_2$ activity in rabbit renal proximal tubule cells (RPTC) was Ca$\^$2+/-independent, localized to the endoplasmic reticulum (ER-iPLA$_2$), and inhibited by the specific Ca$\^$2+/-independent PLA$_2$ inhibitor bromoenol lactone (BEL).(omitted)

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Regulatory Mechanisms of Angiotensin II on the $Na^+/H^+$ Antiport System in Rabbit Renal Proximal Tubule Cells. I. Stimulatory Effects of ANG II on $Na^+$ Uptake

  • Han, Ho-Jae;Koh, Hyun-Ju;Park, Soo-Hyun
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권4호
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    • pp.413-423
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    • 1997
  • The importance of the kidney in the development of hypertension was first demonstrated by Goldblatt and his colleagues more than fifty years ago. Many hormones and other regulatory factors have been proposed to play a major role in the development of hypertension. Among these factors angiotensia II (ANG II) is closely involved in renal hypertension development since it directly regulates $Na^+$ reabsorption in the renal proximal tubule. Thus the aim of the present study was to examine signaling pathways of low dose of ANC II on the $Na^+$ uptake of primary cultured rabbit renal proximal tubule cells (PTCs) in hormonally defined seum-free medium. The results were as follows: 1) $10^{-11}$ M ANG II has a significant stimulatory effect on growth as compared with control. Alkaline phosphatase exhibited significantly increased activity. However, leucine aminopeptidase and ${\gamma}-glutamyl$ transpeptidase activity were not significant as compared with control. In contrast to $10^{-11}$ M ANG II stimulated $Na^+$ uptake $(108.03{\pm}2.16% of that of control)$, $10^{-9}$ M ANG II inhibited ($92.42{\mu}2.23%$ of that of control). The stimulatory effect of ANG II on $Na^+$ uptake was amiloride-sensitive and inhibited by losartan (ANG II receptor subtype 1 antagonist) and not by PD123319 (ANG II receptor subtype 2 antagonist). 2) Pertussis toxin (PTX) alone inhibited $Na^+$ uptake by $85.52{\pm}3.52%$ of that of control. In addition, PTX pretreatment prevented the AMG II-induced stimulation of $Na^+$ uptake. 8-Bromoadenosine 3',5'-cyclic monophosphate (8-Br-cAMP), forskolin, and isobutylmethylxanthine (IBMX) alone inhibited $Na^+$ uptake by $88.79{\pm}2.56,\;80.63{\pm}4.38,\;and\;84.47{\pm}4.74%$ of that of control, respectively, and prevented the ANG II-induced stimulation of $Na^+$ uptake. However, $10^{-11}$ M ANG II did not stimulate cAMP production. 3) The addition of 12-O-te-tradecanoylphorbol-13-acetate (TPA, 0.01 ng/ml) to the PTCs produced significant increase in $Na^+$ uptake ($114.43{\pm}4.05%$ of that of control). When ANG II and TPA were added together to the PTCs, there was no additive effect on $Na^+$ uptake. Staurosporine alone had no effect on $Na^+$ uptake, but led to a complete inhibition of ANG II- or TPA-induced stimulation of Na'uptake. ANG II treatment resulted in a $111.83{\mu}4.51%$ increase in total protein kinase C (PKC) activity. In conclusion, the PTX-sensitive PKC pathway is the main signaling cascade involved in the stimulatory effects of ANG II on $Na^+$ uptake in the PTCs.

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Regulatory Mechanisms of Angiotensin II on the $Na^+/H^+$ Antiport System in Rabbit Renal Proximal Tubule Cells. II. Inhibitory Effects of ANG II on $Na^+$ Uptake

  • Han, Ho-Jae;Park, Soo-Hyun;Koh, Hyun-Ju
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권4호
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    • pp.425-434
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    • 1997
  • Many reports represent that angiotensin II (ANG II) caused a dose dependent biphasic effects on fluid transport in the proximal tubule. However, respective roles of different signaling pathways in mediating these effects remain unsettled. The aim of the present study was to examine signaling pathways at high doses of ANG II on the $Na^+$ uptake of primary cultured rabbit renal proximal tubule cells(PTCs) in hormonally defined serum-free medium. High concentrations of ANG II $(>10^{-9}\;M)$ inhibited $Na^+$ uptake and increased $[Ca^{2+}]_i\;level$ in the PTCs. However, low concentrations of $(<10^{-11}\;ANG\;II)$ stimulated $Na^+$ uptake and did not affect $[Ca^{2+}]_i\;level$. 8-(N, N-diethylamino)-octyl-3,3,5- trimethoxybenzoate (TMB-8), ethylene glycol-bis$({/beta}-amino\;ethyl ether)-N,N,N'$, N'-tetra acetic acid (EGTA), and nifedifine partially blocked the inhibitory effects of ANG II on $Na^+$ uptake. When ANG II and bradykinin (BK) were treated together, $Na^+$ uptake was further reduced $(88.47{\pm}1.98%\;of\;that\;of\;ANG\;II,\;81.85{\pm}1.84%\;of\;that\;of\;BK)$. In addition, W-7 and KN-62 blocked the ANG II-induced inhibition of $Na^+$ uptake. Arachidonic acid reduced $Na^+$ uptake in a dose-dependent manner. When ANG II and arachidonic acid were treated together, inhibitory effects on $Na^+$ uptake significantly exhibited greater reduction than that of each group, respectively. When PTCs were treated by mepacrine $(10^{-6}\;M)$ and AACOCF3 $(10^{-5}\;M)$ for 1 hr before the addition of $(<10^{-9}\;ANG\;II)$, the inhibitory effect of ANG II was reversed. In addition, econazole $(>10^{-6}\;M)$ blocked ANG II-induced inhibition of $Na^+$ uptake. In conclusion, the $[Ca^{2+}]_i$ (calcium-calmodulin-dependent kinase) and phospholipase $A_2\;(PLA_2)$ metabolites are involved in the inhibitory effects of ANG II on $Na^+$ uptake in the PTCs.

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The Roles of Arachidonic Acid and Calcium in the Angiotensin II-induced Inhibition of $Na^+$ Uptake in Renal Proximal Tubule Cells

  • Park, Soo-Hyun;Koh, Hyun-Joo;Lee, Yeun-Hee;Son, Chang-Ho;Park, Min-Kyoung;Lee, Young-Jae;Han, Ho-Jae
    • The Korean Journal of Physiology and Pharmacology
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    • 제3권1호
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    • pp.83-91
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    • 1999
  • Angiotensin II (ANG II) has a biphasic effect on $Na^+$ transport in proximal tubule: low doses of ANG II increase the $Na^+$ transport, whereas high doses of ANG II inhibit it. However, the mechanisms of high dose ANG II-induced inhibition on $Na^+$ uptake are poorly understood. Thus the aim of the present study was to investigate signal transduction pathways involved in the ANG II-induced inhibition of $Na^+$ uptake in the primary cultured rabbit renal proximal tubule cells (PTCs) in hormonally defined serum-free medium. ANG II $(10^{-9}\;M)-induced$ inhibition of $Na^+$ uptake was blocked by losartan $(10^{-8}\;M,\;AT_1\;antagonist),$ but not by PD123319 $(10^{-8}\;M,\;AT_2\;antagonist)$ (P<0.05). ANG II-induced inhibition of $Na^+$ uptake was also completely abolished by neomycin $(10^{-4}\;M,$ PLC inhibitor), W-7 $(10^{-4}\;M,$ calmodulin antagonist), and $AACOCF_3\;(10^{-6}\;M,\;PLA_2\;inhibitor)$ (P<0.05). ANG II significantly increased $[^3H]arachidonic$ acid (AA) release compared to control. The ANG II-induced $[^3H]AA$ release was blocked by losartan, $AACOCF_3,$ neomycin, and W-7, but not by PD123319. ANG II-induced $[^3H]AA$ release in the presence of extracellular $Ca^{2+}$ was greater than in $Ca^{2+}-free$ medium, and it was partially blocked by TMB-8 $(10^{-4}\;M,$ intracelluar $Ca^{2+}$ mobilization blocker). However, in the absence of extracellular $Ca^{2+},$ it was completely blocked by TMB-8. In addition, econazole $(10^{-6}\;M,$ cytochrome P-450 monooxygenase inhibitor) and indomethacin $(10^{-6}\;M,$ cyclooxygenase inhibitor) blocked ANG II-induced inhibition of $Na^+$ uptake, but NGDA $(10^{-6}\;M,$ lipoxygenase inhibitor) did not affect it. In conclusion, $PLA_2-mediated$ AA release is involved in ANG II-induced inhibition of $Na^+$ uptake and is modulated by $[Ca^{2+}]_i$ in the PTCs.

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미꾸라지, Misgurnus mizolepis와 미꾸리, M. anguillicaudatus간 잡종 및 잡종 3배체 일부 조직에서의 세포 및 핵 크기 (Comparison of Some Tissues in Diploid and Triploid Hybrid between Mud Loach, Misgurnus mizolepis and Cyprinid Loach, M. anguillicaudatus)

  • 박인석;김동수
    • 한국발생생물학회지:발생과생식
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    • 제4권1호
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    • pp.19-28
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    • 2000
  • 암컷 미꾸라지, Misgurnus mizolepis와 수컷 미꾸리, M. anguillicaudatus간 잡종과 잡종 3배체를 생산하였으며, 잡종화 및 잡종 3배체화가 망막, 시개 및 trunk kidney에 미치는 영향을 조직학적으로 조사하였다. 잡종은 일부 조직의 핵과 세포 크기에서 양친과 거의 유사하였다. 잡종 3배체는 잡종에 비해 적혈구 세포 및 핵 크기, 망막 내과립층 horizontal cell 핵 크기, 망막신경절 신경세포 층의 신경세포, 시개과립층의 신경세포 핵 및 trunk kidney 2차 근위뇨세관 세포 및 핵 크기에서 증가한 반면 망막 외과립층 수와 2차 근위뇨세관 핵 수에서는 감소하였다. 본 연구 결과 잡종에 비해 잡종 3배체의 일부 조직에서 세포 및 핵 크기 증가를 동반한 세포 수 감소 특성은, 미꾸리류에서의 잡종 및 잡종 3배체의 판별 및 배수화 수준 평가의 한 방편으로 사용 가능할 것이다.

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