Uterine arterial blood flow and the substances of ovarian renin–angiotensin system in women with polycystic ovaries undergoing in vitro fertilization

Author(s):  
Eda Vrtačnik-Bokal ◽  
Helena Meden-Vrtovec ◽  
Ivan Verdenik
1984 ◽  
Vol 246 (1) ◽  
pp. E84-E88
Author(s):  
C. D. Simon ◽  
T. W. Honeyman ◽  
J. C. Fray

The mechanisms whereby the pituitary gland maintains arterial pressure were investigated in rats. The arterial pressure in hypophysectomized rats was 30 mmHg below normal. Saralasin or captopril caused a further fall of 25 and 30 mmHg, respectively, suggesting that the renin-angiotensin system plays a role in blood pressure maintenance in hypophysectomized rats. Growth hormone administration to hypophysectomized rats increased the arterial pressure, but pretreatment with captopril prevented the effect. Plasma renin activity and basal renin secretion (in vitro) was normal in hypophysectomized rats despite a twofold greater renal renin content. Secretory responsiveness to isoproterenol and calcium omission was lower in hypophysectomized rats. It is concluded that the renin-angiotensin system plays a role in maintaining arterial blood pressure in hypophysectomized rats although the responsiveness of the system may be decreased.


1980 ◽  
Vol 239 (4) ◽  
pp. F360-F365 ◽  
Author(s):  
M. Cynthia Blasingham ◽  
Alberto Nasjletti

We studied the renal effects of the cyclooxygenase inhibitor sodium meclofenamate (M) (5 mg/kg, iv) in the pentobarbital-anesthetized dog that had been maintained on an elevated (100 meq/day) or on a reduced (<5 meq/day) sodium intake, and during the administration of angiotensin II in the sodium-replete dog, or the angiotensin receptor blocker [Sar1–Ala8]angiotensin II in the sodium-deprived dog. In the sodium-replete dog, M did not affect mean arterial blood pressure (MABP), renal blood flow (RBF), glomerular filtration rate (GFR), or urine volume (V), but reduced the urinary excretion of sodium (UNa V) by 47%, and of immunoreactive PGE2 (iPGE2) by 90%. However, in the sodium-replete dog during angiotensin II infusion (3 ng · kg-1 · min-1, iv), M reduced RBF by 35%, GFR by 24%, V by 71%, and iPGE2m by 94%. Similarly, in the sodium-deprived dog M reduced RBF by 34%, GFR by 28%, and iPGE2 excretion by 89%. However, M did not affect RBF or GFR in the sodium-deprived dog during infusion of [Sar1-Ala8]angiotensin II (6 μg · kg-1 · min-1, iv), although iPGE2 excretion was reduced by 84%. This study demonstrates that the effects of M on renal hemodynamics in the dog vary with the state of sodium balance and suggests that a prostaglandin(s) contributes to maintenance of renal blood flow during activation of the renin-angiotensin system. meclofenamate; renal prostaglandins; renin-angiotensin system; receptor blocker; renal hemodynamic and excretory function Submitted on October 17, 1979 Accepted on May 9, 1980


2003 ◽  
Vol 98 (6) ◽  
pp. 1338-1344 ◽  
Author(s):  
Gilles Boccara ◽  
Alexandre Ouattara ◽  
Gilles Godet ◽  
Eric Dufresne ◽  
Michèle Bertrand ◽  
...  

Background Terlipressin, a precursor that is metabolized to lysine-vasopressin, has been proposed as a drug for treatment of intraoperative arterial hypotension refractory to ephedrine in patients who have received long-term treatment with renin-angiotensin system inhibitors. The authors compared the effectiveness of terlipressin and norepinephrine to correct hypotension in these patients. Methods Among 42 patients scheduled for elective carotid endarterectomy, 20 had arterial hypotension following general anesthesia that was refractory to ephedrine. These patients were the basis of the study. After randomization, they received either 1 mg intravenous terlipressin (n = 10) or norepinephrine infusion (n = 10). Beat-by-beat recordings of systolic arterial blood pressure and heart rate were stored on a computer. The intraoperative maximum and minimum values of blood pressure and heart rate, and the time spent with systolic arterial blood pressure below 90 mmHg and above 160 mmHg, were used as indices of hemodynamic stability. Data are expressed as median (95% confidence interval). Results Terlipressin and norepinephrine corrected arterial hypotension in all cases. However, time spent with systolic arterial blood pressure below 90 mmHg was less in the terlipressin group (0 s [0-120 s] vs. 510 s [120-1011 s]; P &lt; 0.001). Nonresponse to treatment (defined as three boluses of terlipressin or three changes in norepinephrine infusion) occurred in zero and eight cases (P &lt; 0.05), respectively. Conclusions In patients who received long-term treatment with renin-angiotensin system inhibitors, intraoperative refractory arterial hypotension was corrected with both terlipressin and norepinephrine. However, terlipressin was more rapidly effective for maintaining normal systolic arterial blood pressure during general anesthesia.


2017 ◽  
Vol 312 (5) ◽  
pp. H968-H979 ◽  
Author(s):  
Neeru M. Sharma ◽  
Shyam S. Nandi ◽  
Hong Zheng ◽  
Paras K. Mishra ◽  
Kaushik P. Patel

An activated renin-angiotensin system (RAS) within the central nervous system has been implicated in sympathoexcitation during various disease conditions including congestive heart failure (CHF). In particular, activation of the RAS in the paraventricular nucleus (PVN) of the hypothalamus has been recognized to augment sympathoexcitation in CHF. We observed a 2.6-fold increase in angiotensinogen (AGT) in the PVN of CHF. To elucidate the molecular mechanism for increased expression of AGT, we performed in silico analysis of the 3′-untranslated region (3′-UTR) of AGT and found a potential binding site for microRNA (miR)-133a. We hypothesized that decreased miR-133a might contribute to increased AGT in the PVN of CHF rats. Overexpression of miR-133a in NG108 cells resulted in 1.4- and 1.5-fold decreases in AGT and angiotensin type II (ANG II) type 1 receptor (AT1R) mRNA levels, respectively. A luciferase reporter assay performed on NG108 cells confirmed miR-133a binding to the 3′-UTR of AGT. Consistent with these in vitro data, we observed a 1.9-fold decrease in miR-133a expression with a concomitant increase in AGT and AT1R expression within the PVN of CHF rats. Furthermore, restoring the levels of miR-133a within the PVN of CHF rats with viral transduction resulted in a significant reduction of AGT (1.4-fold) and AT1R (1.5-fold) levels with a concomitant decrease in basal renal sympathetic nerve activity (RSNA). Restoration of miR-133a also abrogated the enhanced RSNA responses to microinjected ANG II within the PVN of CHF rats. These results reveal a novel and potentially unique role for miR-133a in the regulation of ANG II within the PVN of CHF rats, which may potentially contribute to the commonly observed sympathoexcitation in CHF. NEW & NOTEWORTHY Angiotensinogen (AGT) expression is upregulated in the paraventricular nucleus of the hypothalamus through posttranscriptional mechanism interceded by microRNA-133a in heart failure. Understanding the mechanism of increased expression of AGT in pathological conditions leading to increased sympathoexcitation may provide the basis for the possible development of new therapeutic agents with enhanced specificity.


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