• The Korean Journal of Physiology
• /
• v.18 no.1
• /
• pp.1-8
• /
• 1984

In order to determine the extent of the placental transfer of Lithium ion, pregnant rabbits at $27{\sim}29$ days of gestation, which has hemochorial placenta similar to the human placenta, received 2 mM/Kg of $Li^+$ in the form of LiCl intravenously. Maternal arterial blood, placental sinus blood, fetal blood, amniotic fluid and maternal urine were drawn two hours after the single dose of LiCl. Concentrations of $Li^+$, $Na^+$, $K^+$ and osmolarity were measured in plasma of collected bloods, amniotic fluid and urine. Followings are the results obtained. 1) Evident level of $Li^+$ was detected in fetal blood, although fetal plasma concentration of $Li^+$ found to be almost one third of maternal plasma. 2) Plasma concentration of $Li^+$ in placental sinus blood was higher than that in fetal plasma but lower than that in maternal plasma. It means that downward concentration gradient of $Li^+$ from mother to fetus was still remarkable two hours after the injection. 3) Significant level of $Li^+$ was also detected in amniotic fluid. It seemed likely that $Li^+$, at least in part, excreted by the fetal urinary tract. 4) There were no differences in $Na^+$ and osmolar concentration between fetal and maternal blood. 5) From above results, it was concluded that $Li^+$ may transfer across the placenta but limited passage capacity through placental barrier for $Li^+$ is significant, beacause net transfer assumed to be going on even at two hours, at which time maternal equlibrium has been reached.

• BMB Reports
• /
• v.39 no.5
• /
• pp.530-536
• /
• 2006

Thermal conformational changes of human serum albumin (HSA) in phosphate buffer, 10 mM at pH = 7 are investigated using differential scanning calorimetric (DSC), circular dichroism (CD) and UV spectroscopic methods. The results indicate that temperature increment from $25^{\circ}C$ to $55^{\circ}C$ induces reversible conformational changes in the structure of HSA. Conformational change of HSA are shown to be a three-step process. Interestingly, melting temperature of the last domain is equal to the maximum value of fever in pathological conditions, i.e. $42^{\circ}C$. These conformational alterations are accompanied by a mild alteration of secondary structures. Study of HSA-SDS (sodium dodecyl sulphate) interaction at $45^{\circ}C$ and $35^{\circ}C$ reveals that SDS affects the HSA structure at least in three steps: the first two steps result in more stabilization and compactness of HSA structure, while the last one induces the unfolding of HSA. Since HSA has a more affinity for SDS at $45^{\circ}C$ compared to $35^{\circ}C$, It is suggested that the net negative charge of HSA is decreased in fever, which results in the decrease of HSA-associated cations and plasma osmolarity, and consequently, heat removal via the increase in urine volume.

• Korean Journal of Plant Tissue Culture
• /
• v.21 no.2
• /
• pp.77-84
• /
• 1994

To assess the feasibility of anthocyanin production in cell cultures of Euphorbia splendens Bojer the role of sucrose in pigment production was investigated and pilot scale cultures were attempted to establish mass production system. And also, several instrumental analyses were conducted to identify the pigment extracted from cultured rolls. Anthocyanin production was promoted prominently with concenetrations of sucrose ranging from 3% to 9% while cell growth was maximized at 3% of sucrose . This suggested that high osmolarity of sucrose enhance pigment production. When cells were cultured in two types of bioreactor better cell growth was achieved with draft-type air lift bioreactor than impeller type bioreactor and the pigment productivity was reached to 2.2 mg/L/day. The major pigment extracted from cultured cells was characterized as cyanidin-3-glucoside.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.23 no.2
• /
• pp.155-166
• /
• 1990

There have been many problems like plasmolysis in the ultrastructural studies with kelps. The present study was conducted with series of different fixatives and buffer solutions and several resins to solve the plasmolysis phenomena. The fixative of 1470 mosmol($3\%$ glutaraldehyde, $2.4\%$ paraformaldehyde in 0.05M cacodylate buffer with 0.2M sucrose and $0.5\%$ caffeine at pH of 7.2) showed the least frequency of plasmolysis. The relationship between the concentration of primary fixatives and the frequency of plasmolysis was not found. With above fixative the possibility of plasmolysis during infiltration period was not identified using ultra-low viscosity resin. Generally, the kelp(Laminaria religiosa) contains a lot of mucilage, which interupts the infiltration of fixative. The possible physiological mechanisms related with mucilage secretion may be unable to fix the region of plasmalemma properly.

• Biomedical Science Letters
• /
• v.7 no.4
• /
• pp.211-216
• /
• 2001

This studs was carried out to evaluate KBrO$_3$-induced acute toxicity by clinical pathological parameters in rats. Fourty rats were divided into 4 groups including normal group and three KBrO$_3$-treated groups with doses of 200, 300, and 400 mg/kg, p. o., respectively. Creatinine and BUN were increased remarkably by KBrO$_3$ at 400 mg/kg, respectively (p<0.05, p<0.01). Phosphorus content increased two times the control at 400 mg/kg (p<0.05). Osmolarity was increased, whereas $CO_2$ content showed decrease at 400 mg/kg, respectively (p<0.01, p<0.05). Histopathological findings also showed dose-dependent renal failure. On the other hand, AST was increased three times the control at 400 mg/kg (p<0.01). WBC was increased by KBrO$_3$ depending on the dosage. Platelet was decreased at 200 mg/kg, whereas it was increased at 400 mg/kg (p<0.05). The results above suggest that clinical pathological parameters could be used as indices for the evaluation of KBrO$_3$-induced acute toxic reponse occuring in not only kidney but other organs including liver, when the dosage is as high as 400 mg/kg.

• The Korean Journal of Physiology and Pharmacology
• /
• v.3 no.2
• /
• pp.157-164
• /
• 1999

To determine molecular mechanisms of Aquaporin-CD (AQP2) gene regulation, the promoter region of the AQP2 gene was examined by transiently transfecting a promoter-luciferase reporter fusion gene into mouse renal collecting duct cell lines such as mIMCD-3, mIMCD-K2, and M-1 cells, and NIH3T3 mouse embryo fibroblast cells. PCR-Southern analysis reveals that mIMCD-3 and mIMCD-K2 cells express AQP2, but M-1 and NIH3T3 cells do not, and that the treatment with cpt-cAMP $(400\;{\mu}M)$) or forskolin/isobutylmethylxanthine (IBMX) increased the AQP2 expression in IMCD cells. In both IMCD and NIH3T3 cells, the constructs containing the promoter of AQP2 gene showed promoter activities, indicating lack of tissue-specific element in the 1.4 kb 5'-flanking region of the mouse AQP2 gene. Luciferase activity in the IMCD cells transfected with the construct containing 5-flanking region showed responsiveness to cpt-cAMP, indicating that the 1.4 kb 5'-flanking region contains the element necessary for the regulatory mechanism by cAMP. The promoter-luciferase constructs which do not have a cAMP-responsible element (CRE) still showed the cAMP responsiveness in IMCD cells, but not in NIH3T3 cells. Increase in medium osmolarity did not affect AQP2 promoter activity in mIMCD-K2 cells. These results demonstrate that AQP2 gene transcription is increased with cAMP treatment through multiple motifs including CRE in the 5'-flanking region of the gene in vitro, and the regulatory mechanism may be important for in vivo regulation of AQP2 expression.

• Journal of Fisheries and Marine Sciences Education
• /
• v.26 no.1
• /
• pp.214-222
• /
• 2014

Hagfish Eptatretus burgeri is classified as a agnathans and has many different physiological properties compared with vertebrates. In this study, we examined effects of water temperature and salinity on blood properties and oxygen consumption in hagfish. In the experiment of water temperature change, hematocrit (Ht), red blood cell (RBC) and glucose of hagfish blood revealed the lowest values at $15^{\circ}C$. Oxygen consumption of hagfish had significantly increased with rising water temperature, and the increasing rate was twice as much when the temperature was manipulated every $5^{\circ}C$. Also, oxygen consumption during the night time (a short photoperiod) was significantly higher than that of the daytime. Q10 level was 3.50 in the light period and 3.92 in the dark period. No significant change in plasma glucose level was showned in changing salinity from 30 psu to 22 psu, while it had rapidly increased at 20 psu ($13.7{\pm}4.0mg/dL$) and thereafter all hagfish were dead at 18 psu. However, osmolarity, $Na^+$, $K^+$ and $Cl^-$ levels had significantly decreased when salinity decreased. This results are expected to develop the artificial rearing techniques of natural hagfish.

• Proceedings of the Korean Society of Food and Cookery Science Conference
• /
• 1987.06a
• /
• pp.92-106
• /
• 1987

$Na^{+}$는 체내에서 세포외액 (extracellular fluid)의 주요 양이온으로 세포내액과 세포외액은 세포막을 사이에 두고 $Na^{+}$와 $K^{+}$의 높은 농도의 차이를 유지하고 있다. 이러한 농도차이는 세포막에 있는 $Na^{+}$-K$^{+}$ATP ase의 활동에 의하여 유지되며 $Na^{+}$는 체액의 osmolarity와 혈장의 부피 유지, 신경흥분, 근육수축 및 영양소등의 이동에도 중요한 역할을 한다. 체내의 Na balance는 renin-aldosterone system에 의하여 신장에서의 배설조절로 이루어지며, 최근 Na대사에 관여하는 natriuretic hormone이 발견되고 있다. Na의 과잉섭취는 역학적 연구와 동물실험에서 고혈압의 유발인자로 제시되고 있으나, 임상적 연구에서는 Na제한이 혈압강하효과가 있다는 보고와 없다는 보고가 있어 결과가 뚜렷하지 않다. 이는 고혈압 환자중에는 salt-sensitive한 group자 salt-resistant group이 있다는 것과 산업화된 사회들의 Na 섭취량이 이미 너무 높은 수준으로 Na섭취증가와 혈압상승간의 관계를 현재의 연구 방법들로는 찾아내기 어렵다는 ‘saturation effect’로 설명한다. 그러나 Na섭취를 1일 70~100mEq.(NaCl 4.0~5.8g)이하로 줄이면 고혈압 발생이 현저히 감소하고 Na 섭취량이 1일 30mEq.(NaCl 1.7g)이하이면 고혈압은 거의 발생하지 않는다. 그러나 Na섭취가 1일 400mEq.(NaCl 23.2g)이상이 되더라도 인구 중 50~80%는 고혈압에 걸리지 않아 고혈압의 발생은 유전적 인자, 신장 기능의 부족에 의해 지배되고, Na이외에도 K, Ca등의 식이 인자 및 stress, 운동등의 환경적 요인들이 영향을 미친다. Na 섭취량은 자연식품에 들어있는 양 뿐 아니라, 가공과정, 조리가정, 식사 중에 첨가되는 양에 의하여 좌우되므로, Na 섭취량을 측정하기 매우 어렵다. 가장 널리 사용되는 방법은 24시간 소변 중 배설되는 Na의 양으로부터 추정하는 방법으로 우리나라의 경우, 이러한 방법으로 섭취량을 환산할 경우 1일 200~260mEq. (NaCl 11.6~15.1g) 정도이며 이중 80% 이상이 discretionary intake인 것으로 추정된다. 따라서 앞으로 Na섭취를 줄이도록 많은 노력을 기울여야 하겠다.

• The Korean Journal of Physiology
• /
• v.29 no.1
• /
• pp.81-89
• /
• 1995

The effects of prolactin and vasopressin on the regulation of amniotic fluid (AF) volume and its $Na^{+}$ concentration $([Na^{+}])$ through the membrane surrounding the AF during increase in AF volume due to fetal urination were studied. About 70% of AF volume was replaced with normal isotonic saline solution. Isotonic saline solution (0.5 ml) containing Censored and LiCl was introduced into each amniotic sac. Vasopressin (25 ng/ml) or prolactin (1 mg/ml) of AF was then injected into experimental amniotic sac. The concentrations of Congored, $Li^{+}$, and $Na^{+}$ were measured at 30 and 60 min intervals after injection. Af samples with decreased Censored concentration ([CR]) during the period of 30 - 60 min were analyzed. The percentage change of $[Na^{+}]$ and the rate of $Li^{+}$ movement during this period were calculated, and the effects of vasopressin and prolactin on them were evaluated. Fellowing results were obtained: 1. The rate of reduction of [CR] in the AF was retarded by vasopressin or prolactin injection. 2. The rate of reduction of $[Li^{+}]$ in the AF was also retarded by vasopressin or prolactin injection. 3. The rate of reduction of $[Li^{+}]$ in the AF was less retarded by vasopressin than that of [CR]. 4. $[Na^{+}]$ changed to approach to the normal level, but this was markedly retarded by prolactin injection. 5. Direction of $Li^{+}$ movement was correlated with the change in $[Na^{+}]$ but it always moved out of the amniotic sac even when the $[Na^{+}]$ increased in vasopressin injected AF. From the above results, it is suggested that vasopressin in the AF triggers the fetus to urinate, and then the membranes surrounding the AF regulate osmolarity by efflux of $Na^{+}$. We suggest that prolactin facilitates water outflow across the amniotic membrane during increase in AF volume, in contrast to a constant volume, whereas regulation of $[Na^{+}]$ is partly restricted by prolactin.

• The Korean Journal of Physiology
• /
• v.7 no.2
• /
• pp.39-47
• /
• 1973

The influences of the acute hemorrhage on the intestinal functions were studied in the rabbits subjected to acute bleeding, amounting 1.5-2% of the body weight. The motility and the absorptive capacity of the ileum were compared before and after the bleeding. Transfusion of shed blood was also performed in order to see whether the deteriorations were reversible or not. The tension developed in the direction of the longitudinal axis of the ileum was recorded through an appropriate transducer, and the frequency of the rhythmic contraction was counted throughout the procedure. Test solution, 10ml in amount, was placed in the loop of the ileum, and the samples were drawn at zero time and at 20 minutes. Triplicated procedures were repeated on the same loop;namely, before and after bleeding and after transfusion. The test solution was composed of 200 mg% urea, 218 mEq/l of NaCl and 150 mg% of polyethylene glycol (PEG) No. 4,000 in distilled water. The latter substance was used as a marker substance for the volume change of the loop. The results obtained were as follows; 1. The motility of the ileum suffered little effects by acute hemorrhage. However, minor fluctuations were seen in the frequency of the rhythm, showing a slight tendency of decreasing rhythmicity, and it was reversed by transfusion. 2. Diminution of absorptive capacity of urea was noticed in acute hemorrhage and it was interpreted as the consequence of the secondary effect of the retardation of the active transport mechanism governing the sodium transport 3. Absorption rate of the sodium ion was dropped in the hemorrhage, suggesting the indispensable need of the blood supply. 4. Osmolarity of the luminal fluid remained higher in the case of acute hemorrhage. 5. There was a tendency of retaining more fluid in the intestinal lumen in acute hemorrhage, comparing with that observed prior to the bleeding. 6. The deteriorations in the absorptive capacity were restored by transfusion of shed blood.