• Asian-Australasian Journal of Animal Sciences
• /
• v.17 no.11
• /
• pp.1570-1574
• /
• 2004

A flock of AA breed chickens were reared in peterstme brood-vait chamber and were provided with high energy pelleted feed. At 14 d of age, a total of 350 birds were randomly divided into 3 groups as follows: 100 birds were exposed to normal ambient temperature of 20$^{\circ}C$ for control group; 150 birds were exposed to lower ambient temperature of 11$^{\circ}C$ to induce ascites (treatment I); and another group of 100 birds were exposed to lower ambient temperature of 11$^{\circ}C$ and fed diet containing 1% L-arginine for ascitic prophylactic treatment (treatment II). Samples were collected from blood and abdominal fluid of chicken at 3, 4, 5, 6 and 7 wk of age subsequently, to analysis the contents of plasma endothelin (ET-1), angiotensin II (Ang II), cyclic adenosine monophosphate (cAMP), cyclic guanosine monophosphate (cGMP). The results indicated that the contents of cAMP, cGMP, and Ang II in reatment I and ascitic broilers were higher than the corresponding control group (p<0.01, p<0.05), ET-1 of preascitic broilers were control group (p<0.05), while there was an insignificant difference with later ascitic broilers. The contents of cAMP and cGMP in treatment II were higher than the treatment I and control groups (p<0.01, p<0.05), whereas, the contents of Ang II were gradually decreased compared to the control group (p<0.05), the contents of ET-1 were insignificantly different. On further analysis, the increased plasma Ang II at low ambient temperature condition in broilers made endothelium cell secretion of increased ET-1, cAMP, cGMP and decreased NO. Therefore, low temperature accelerated ascites syndrome in broilers. Supplemently L-arginine can decrease ET-1, and increase cAMP and cGMP. It is concluded that cAMP mediated in broilers pulmonary hypertension syndrome.

• The Korean Journal of Physiology and Pharmacology
• /
• v.4 no.2
• /
• pp.137-142
• /
• 2000

The physiological roles of brain angiotensin II in mediating water deprivation-induced drinking and in regulating renal renin release were assessed in male Sprague-Dawley rats. Specific $AT_1$ receptor antagonists, losartan and SK 1080, and antisense oligonucleotide (AS-ODN) directed to $AT_1$ receptor mRNA were intracerebroventricularly (i.c.v.) administered in conscious unrestrained rats. When water was given 20 min after i.c.v. injection of $AT_1$ receptor antagonists in 48-h water-deprived rats, losartan and SK 1080 produced approximatly 20% and 50% decrease in 1-h water intake, respectively. In contrast, i.c.v. treatment of the AS-ODN to $AT_1$ receptor mRNA for 24-h did not alter 1-h water intake in 24-h water-deprived rats, but prevented the increase in overnight water intake after 24-h water-deprivation. Six-day i.c.v. treatment of AS-ODN did not alter either the basal plasma renin concentration or renal cortical levels of renin and renin mRNA. The present results suggest that endogenous brain Ang II plays an important role in thirst and water intake through $AT_1$ receptors, but further studies are required to elucidate its regulatory role in renal renin synthesis.

• Asian-Australasian Journal of Animal Sciences
• /
• v.21 no.4
• /
• pp.538-546
• /
• 2008

Large-type goats eating dry forage secreted large volumes of saliva which resulted in the loss of $NaHCO_3$ from the blood and decreased plasma volume (hypovolemia). This research investigated whether or not the loss of $NaHCO_3$ from the blood and hypovolemia brought about by dry forage feeding actually depresses feed intake in large-type goats under free drinking conditions. The present experiment consisted of three treatments (NI, ASI, MI). All treatments in this experiment were carried out under free drinking conditions. In the NI control (NI), a solution was not infused. In the ASI treatment, i.v. infusion of artificial saliva was initiated 2 h before feeding and was continued for a total of 3 h concluding 1 h after the commencement of the feeding perod. In the MI treatment, mannitol solution was infused to replenish only water lost from the blood in the form of saliva. The hematocrit and plasma total protein concentrations during feeding in the NI control were observed to be higher than pre-feeding levels. This indicated that dry forage feeding-induced hypovolemia was caused by the accelerated secretion of saliva during the initial stages of feeding in freely drinking large-type goats. Increases in hematocrit and plasma total protein concentrations due to dry forage feeding were significantly suppressed by the ASI treatment. While hematocrit during feeding in the MI treatment was significantly lower than the NI control, plasma total protein concentrations were not different. From these results, it is clear that the MI treatment was less effective than the ASI treatment in mitigating the decreases in plasma volume brought about by dry forage feeding. This indicates that plasma volume increased during dry forage feeding in the ASI treatment which inhibited production of angiotensin II in the blood. The ASI treatment lessened the levels of suppression on dry forage feeding, but the MI treatment had no effect on it under free drinking conditions. The results indicate that despite the free drinking conditions, increases in saliva secretion during the initial stages of dry forage feeding in large-type goats caused $NaHCO_3$ to be lost from the blood into the rumen which in turn caused a decrease in circulating plasma volume and resulted in activation of the renin-angiotensin system and thus feeding was suppressed.

• The Journal of Internal Korean Medicine
• /
• v.19 no.2
• /
• pp.159-184
• /
• 1998

The aim of the study was the experiment of the effect that Kami-Daesihotang had on the essential hypertension and hyperlipidemia. Rats were orally administered with Kami-Daesihotang for 30days and the constituent of the plasma and serum were analysed at the 10th, 20th and 30th day from the first day of experiment, respectively. The heart rate, blood pressure, plasma renin activity, plasma level of aldosterone, catecholamine, sodium and angiotensin II were measured after an oral administration of Kami-Daesihotang in SHR. In addition, serum levels of total cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol and total lipid were measured with cholesterol-fed rats. The results were summarized as following ; 1. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang remarkably decreased the blood pressure in SHR. 2. Double-dosage Kami-Daesihotang were recognized as having the effect on the decreased of the pulse rate in SHR. 3. Plasma renin activity was significantly decreasd in SHR after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 4. Double-dosage Kami-Daesihotang considerably reduced the plasma angiotensin level in SHR. 5. Noticeable decreased of plasma norepinephrine level was showed in SHR, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 6. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang noticeable reduced body weight in hyperlipidemia rats which had fed with 1% cholesterol. 7. Single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang had a significantly decreasing effect on serum total cholesterol in hyperlipidemia rats which had fed with 1% cholesterol. 8. Serum triglyceride level was importantly decreased in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 9. Remarkable decreased of serum low density lipoprotein cholesterol level was found in hyperlipidemia rats which had fed with 1% cholesterol, after single-dosage Kami-Daesihotang & double-dosage Kami-Daesihotang treatment. 10. Double-dosage Kami-Daesihotang was showed a significantly decreasing effect on serum total lipid level in hyperlipidemia rats which had fed with 1% cholesterol. 11. Single-dosage Kami-Daesihotang noticeably reduced organ weight of liver, kidney, spleen and testis in hyperlipidemia rats which had fed with 1% cholesterol. Double-dosage Kami-Daesihotang significantly decreased organ weight of liver, kidney and spleen in hyperlipidemia rats. These Findings suggest a possible anti-hypertensive and hyperlipidemic effect of Kami-Daesihotang.

• The Korean Journal of Pharmacology
• /
• v.20 no.2
• /
• pp.1-6
• /
• 1984

It has been generally recognized that the secretion of aldosterone is mainly regulated by angiotensin II in animals and humans, however, potassium and ACTH are also proposed as other humoral factors involved in the aldosterone secretory process. Recently, stress, anesthesia, adrenergic stimulation, low sodium intake or water deprivation stimulate plasma renin activity, while high sodium intake and deoxycorticosteroid have been reported to cause suppression of renin activity in animals. It seems that overall response of aldosterone secretory mechanisms reflects complex interactions both intrarenal and extrarenal components. Furosemide has been widely used to investigate the control of renin secretion by the kidney, and the relationship between diuretics and the disposition of endogenous aldosterone were reported (Oh, 1984). The sequential with 10 min interval samples of plasma were collected following administration of furosemide(1 mg/kg), aspirin(10 mg/kg), respectively. And also similar experiment was performed in the propranolol (10 mg/kg) pretreated rabbits. The results were as follows : 1) The concentration of plasma aldosterone was average of $426.I{\sim}485.5pg/ml$ in normal rabbits. Plasma concentrations of aldosterone rised significantly after injection of furosemide during 50 min, and the rise of plasma aldosterone was blocked by the propranolol pretreatment 2) Significant fall in the plasma level of aldosterone after injection of aspirin was noted. This result indicates that the increased secretion of aldosterone induced by furosemide administration is mediated through ${\beta}-receptors$, and the possible role of prostaglandin is substantiated.

• BMB Reports
• /
• v.51 no.12
• /
• pp.611-612
• /
• 2018

$C1q/TNF-{\alpha}-Related$ Protein 1 (CTRP1) has recently been shown to act as a blood pressure regulator, as it induces vasoconstriction. In the aorta, CTRP1 facilitates recruitment of angiotensin II receptor 1 (AT1R) to plasma membrane, through activation of the AKT/AS160 signaling pathway. This leads to activation of the Ras homolog gene family (Rho)/Rho kinase (ROCK) signaling pathway, resulting in vasoconstriction. Accordingly, mice overexpressing Ctrp1 have hypertensive phenotype. Patients with hypertension also display higher circulating CTRP1 levels, compared to healthy individuals, indicating that excessive CTRP1 may affect development of hypertension. Conversely, CTRP1 is regarded as an 'innate blood pressure modulator' because CTRP1 increases blood pressure under dehydration to prevent hypotension. Mice lacking Ctrp1 fail to maintain normotension under dehydration conditions, resulting in hypotension, suggesting that CTRP1 is an essential protein for maintaining blood pressure homeostasis. In conclusion, CTRP1 is a novel, anti-hypotensive vasoconstrictor that increases blood pressure during dehydration-induced hypotension.

• The Journal of Korean Medicine
• /
• v.20 no.1 s.37
• /
• pp.185-196
• /
• 1999

The aim of the present study was to investigate the effect of Hwangryeonheadock-Tang and Onchung-Eum on essential hypertension and hyperlipidemia. Rats were orally administered for 30days with Hwangryeonheadock-Tang and Onchung-Eum and the blood was withdrawn at 10, 20 and 30days after an oral administration. The heart rate, tail blood pressure, plasma renin activity, plasma level of aldosterone. catecholamine, sodium and angiotensin II were measured after an oral administration of Hwangryeonheadock-Tang and Onchung-Eum in spontaneously hypertensive rat(SHR). In addition, serum levels of total cholesterol, triglyceride, HDL-cholesterol. LDL-cholesterol and total lipid were measured cholesterol-fed rats. The results were summarized as follows ; 1. A significant decrease of tail blood pressure was shown at 10, 20 and 30days after Hwangryeonheadock-Tang and Onchung-Eum treatment in SHRs. compared with saline. 2. Heart rate was significantly decreased at 30days in SHRs after Hwangryeonheadock-Tang treatment and at 20, 30days after Onchung-Eum treatment in SHRs. compared with the effects of saline group. 3, A significant decrease of plasma aldosterone level was elicited at 10, 20days after Hwangryeonheadock-Tang treatment in SHRs, compared with the effects of saline group, 4. Plasma renin activity was significantly decreased at 10days after Onchung-Eum treatment compared with the effects of saline group in SHRs. 5. Plasma norepinephrine level was significantly decreased at 20 and 30clays after Onchung-Eum treatment in SHRs, compared with the effects of saline group. 6. A significant decrease of plasma epinephrine level was induced at 30days after Hwangryeonheadock-Tang treatment and at 10, 20 and 30days after Onchung-Eum treatment, compared with the effects of saline group in SHRs. 7. Plasma sodium level was. significantly decreased at 20days after Hwangryeonheadock-Tang and Onchung-Eum treatment, compared with the effects of saline group in SHRs. 8. Plasma angiotensin II level was significantly decreased at 30days after Onchung-Eum treatment, compared with the effects of saline group in SHRs. 9. A significant decrease of body weight was observed at 20 and 30days after Hwangryeonheadock-Tang treatment and at 10, 20 and 30days after Onchung-Eum treatment. compared with the effects of saline group in hyperlipidemia rats. 10. Hwangryeonheadock-Tang and Onchung-Eum showed a significantly decreasing effect at 30days on serum total cholesterol level in hyperlipidemia rats, compared with the saline treatment. 11. Hwangryeonheadock-Tang and Onchung-Eum saw 20 and 30days respectively on serum triglyceride level in the saline treatment. 12. Hwangryeonheadock-Tang and Onchung-Eum decreased on serum HDL-cholesterol level significantly, compared with the saline treatment in hyperlipidemia rats. 13. A significant decrease of serum LDL-cholesterol was observed at 10 and 30days after Hwangryeonheadock-Tang treatment and at 30days after Onchung-Eum treatment, compared with the effects of saline group in hyperlipidemia rats. 14. Hwangryeonheadock-Tang had a significantly decreasing effect at 10, 20 and 30days on serum total lipid level, compared with the saline treatment in hyperlipidemia rats. 15. Hwangryeonheadock-Tang elicited a significantly decreasing effect on weight of kidneys, spleen and testes respectively and Onchung-Eum induced on weight of liver and spleen respectively in hyperlipidemia rats, compared with saline treatment. These Findings suggest a possible anti-hypertensive and anti-hyperlipidemic effect of Hwangryeonheadock-Tang and Onchung-Eum.

• The Korean Journal of Physiology
• /
• v.29 no.2
• /
• pp.259-267
• /
• 1995

The renin-angiotensin system plays an important role in the regulation of blood pressure and in body fluid homeostasis. There is increasing evidence for generation of endogenous angiotensin II in many organs and for its role in paracrine functions. Studies were designed to investigate whether hemorrhage produces rapid changes in the gene expression of angiotensinogen in peripheral and brain tissues. Wistar rats received saline drinking water for 7 days, were bled at a rate of $3\;ml\;kg^{-1}\;min^{-1}$ for 7 min, and then decapitated 0, 2, 4, 8, or 24 hr after hemorrhage. Hemorrhage produced a produced hypotension with tachycardia at $2{\pm}8\;hr$, but blood pressure and heart rate had not fully recovered to the basal level at 24 hr. Plasma renin concentration was significantly increased at 2, 4, and 8 hr (maximum sixfold increase at 4 hr) and had returned to the basal level at 24 hr. Renal renin content was significantly increased only at 4 hr after hemorrhage. Angiotensinogen mRNA in both the kidney and liver were stimulated at 2 to 8 hrs, but recovered to the basal level at 24 hr. On the other hand, angiotensinogen mRNA levels il the hypothalamus and brainstem were continuously increased from 2 to 24 hrs. The present study demonstrates the presence of angiotensinogen mRNA in both hepatic and extrahepatic tissues, and more importantly, their up-regulation after hemorrhage. These results suggest that the angiotensinogen-generating systems in the liver, kideny and brain are, at least in part, under independent control and play a local physiological role.

• The Korean Journal of Physiology and Pharmacology
• /
• v.1 no.2
• /
• pp.151-159
• /
• 1997

In an attempt to investigate whether hemorrhage affects the gene expression of the renin-angioteusin system (RAS) components in the brain and peripheral angiotensin-generating tissues, changes in mRNA levels of the RAS components in response to hemorrhage were measured in conscious unrestrained rats. Wistar rats were bled at a rate of 3 ml/kg/min for 5 min, and then decapitated 7 h after hemorrhage. Levels of mRNA for renin, angiotensinogen and angiotensin $II-AT_1$ receptor subtypes ($AT_{1A}$ and $AT_{1B}$) were determined with the methods of northern blot and reverse transcriptase-polymerase chain reaction (RT-PCR). Hemorrhage produced a profound hypotension with tachycardia, but blood pressure and heart rate recovered close to the basal level at 7 h. Plasma and renal renin levels were significantly increased at 7 h. Hemorrhage induced rapid upregulation of gene expression of both $AT_{1A}$ and $AT_{1B}$ receptor subtypes in the brainstem and hypothalamus, downregulation of them in the adrenal gland and liver. However, renin mRNA level increased in the brainstem, decreased in the liver, but was not changed in the hypothalamus, kidney and adrenals after hemorrhage. Angiotensinogen mRNA level was not significantly changed in any of the tissue except a slight increase in the liver. The kidney and liver did not show any significant change in gene expression of the RAS components. These results suggest that gene expression of the RAS in central and peripheral tissues are, at least in part, under independent control and the local RAS in each organ plays specific physiologic role.

• Journal of Nutrition and Health
• /
• v.35 no.8
• /
• pp.840-847
• /
• 2002

This study explored the effect of dietary levels of Na and Ca on spontaneously hypertensive rats (SHR). SHR were randomly divided into 5 groups and fed a high fat/cholesterol diet containing three levels of Na (0.05, 0.1, 1.5%) and Ca (0.1, 0.5, 1.5%) for 9 weeks. Body weight gain was not influenced by dietary intake but water intake significantly increased in high Na supplementation. Systolic blood pressure was not influenced by dietary Na and Ca levels but was decreased by dietary low Na/high Ca levels at 9 weeks. Angiotensin-II level was affected by dietary Na level but not by Ca levels. Plasma Ca, Mg, K and Na levels were in the normal range regardless of dietary Na and Ca levels. Weight, and K and Na contents of the heart and kidney were not significantly different among those with different dietary Na and Ca levels. Ca and Mg contents of the heart and kidney were significantly higher in the normal Na/normal Ca group. Ca and Mg in the feces were higher in those with high Ca intake. Na in the feces was higher in those with high Na intake. Therefore, Na and Ca had different mechanisms in the hypertension/hyperlipidemia models, respectively. And we suggested that Mg must be supplemented when Ca intake was high because Mg excretion was increased by Ca supplementation.