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Does chronic estrogen act as a converting enzyme inhibitor in postmenopausal cynomolgous monkeys?
POSTERS: Renin!Angiotensin!Adrenal Hormones 107A
AJH-APRIL 1995-VOL.8, NO.4, PART 2
BI0
B9 PLASMA LEVELS OF POTASSIUM, ALDOSTERONE, RENIN, AND THE ALDOSTERONE/RENIN RATIO IN PATIENTS WITH 'AIDOSTERONE-PRODUCrNG ADENOMA: RElATION TO DIAGNOSIS AND BLOOD PRESSURE OUTCOME. C Masslen.sJmQn" C Ballaglla, G Chatelller, TT Guyene, PF Plouin. HOpilal Broussars and Ihe COMETE network, Paris, France. To evaluale diagnostic tests for aldosterone-producing adenoma (APA), we compared plasma levels of potassium (K), aldosterone, renin, and the aldoslerone/renln (NR) ratio In 60 patients with surgIcally-proven APA, 50 patients with essential hypertension, and 49 normal volunteers. We also studIed Indicators predictive of postoperative blood pressure (BP) outcome In APA patients (improvement: diastolic BPS105 mmHg and reduced by ~15%; normallzatlon: DBP<90 mmHg wllhout treatment). Sensitivities (se) and speclfi~ities (sp) were determined after threshold optimizatfon using ROC curves and we then compared the Youden ind:ces (se+sp-1) of the dlffereJll tests. Although mean K levels were lower in APA than in EH (p
Key Words:. aldosterone-producing adenoma, potassium, aldosterone/renin ratio, ROC curves.
DOES CHRONIC ESTROGEN ACT AS A CONVERTING ENZYME INHIBITOR IN POSTMENOPAUSAL CYNOMOLGOUS MONKEYS? KB Brosnihan, D Weddle, MS Anthony, and CM Ferrario*• Bowman Gray School of Medicine, Winston-Salem, NC. To determine the effects of estrogen or estrogen and
progestin on the renin-angiotensin system. forty-five surgically postmenopausal cynomolgus monkeys were given either a conjugated equine estrogen (Premarin, 166 /lgJday), alone or in combination with medroxprogesterone acetate (Cycrin, 650 Ilg/day) for 30 months, or left with no hormone replacement therapy. Animals were anesthetized with ketaminepentobarbital, and samples were taken for themeasurement of plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity and angiotensin peptides [Ang I, Ang II, and Ang·(l-1)J. Chronic replacement therapy with estrogen resulted in a significant reduction in ACE (229 ± 8 vs 189 ± 10 nmol/ml/min, p < 0.05, untreated vs estrogen), whereas the combination therapy of estrogen and progestin significantly elevated PRA (11.1 ± 2.0 vs 32.8 ± 4.9 nglmllmin, untreated vs combined therapy). Both of these changes in processing enzymes observed during estrogen or the combination therapy resulted in significant increases in plasma Ang I levels [46.7 ± 12,5 pg/ml (untreated) vs 175.5 ± 65.9 pglml (estrogen) and 561.7 ± 373.6 pg/ml (combination therapy). These studies reveal that chronic estrogen replacement selectively reduces ACE activity, whereas the combination of estrogen and progestin augments PRA. Thu., hormonal replacement shifts the processing of angiotensin peptides, making available more of the immediate precursor of the biologically active angiotensin peptides, Key Words: reni~. angiotensin, estrogen, progestin ovariectomy
B11
B12
HIGH ANG II LEVELS IN PLASMA OF ~REGNANT WOMEN REDUCED AFTER HPLC: MULTIPLE .rANG II PEAKS DETECTED
REGULATION OF ATl RECEPTOR mRNA IN RAT TISSUES. ~*. CA Griffin. G Giacchelli, JP Vatentin. C Llorens-Cones. P Corvol, and M Scbambelan. University of California San Francisco. CA; University of Udine, Italy; and College de France, Paris. France. In theadult kidney, theATI angiotensin (Angll) rccepror suvtype predominates. To study regulation of ATl receptor subtype gene expression in the rat. we altered activity of the renin-angiotensin system by: I) ingestion of a low- (LS. 0.07% Nae) or high- (HS. 7.5%) salt chow for 14 days; 2) infusion of AnglI (200 ng/kg,lmin. Lp.) or the vehicle (VEH) for 7 days; treatment with an angiotensin converting enzyme inhibitor (eaptopril, 100 mg,ldl. in the drinking water) or vehicle for 7 days. Renin. angiotensinogen, and ATI mRNA levels were measured byslot-bIOI and Northern hybridization using cRNA probes. ATtaand ATtb mRNA were determined byRT· PCR In thepresence ofa cRNA internal standard. Renal renin. renal and hepatic angiotenslnogen, and hepatic ATI mRNA levels were all
A C Bragat, P August·, J Oacclebaudo", J E Sealey· Cardiovascular Center, Cornell University Medical College, New York, NY
In pregnancy, high angiotensin (Ang) II levels have been reported in relalion to the circulating levels 01 plasma renin. In this report we investigate whether immunoreactive (i,') Ang II levels differ when plasma is pra,axtracted with phanylsilyl-silica Bond·EIut (8-E) rathar than Ct8 Sep·Pak (S-P) cartridges and when theextract ispurified by HPLC. Plasma from 5 pregnant women wasextracted using B-E or Sop cartridges. The irAng II levels were diractly quantified byradioimmunoassay. Also, Ang II was isolated using Isocratlc reversed-phase HPLC (as described by Nussbarger st al)lollowed .,ltar15 minutes by a gradient otIncreasing methanol (see Ailas at al abstract), The true Ang " peak elutad after 6 minutas, butother unidentified irAng It peaks were detected during thegradient, after 26 minutes. irAng II levels expressed in pglml are as follows: HPLC Angll Sop B-E 1.5 2.2
noHPLC
s·p
8-E 2.7 14
12
15
12
5.6
4.9 11
2.2
5.8
22 33 11
1.3
17 41 20 60 20
7.6 :1:2.4
17 :t4.7
2.7 ±1.4
3211*
12
:1:8.3
:t2."
12 5.2
mean sem
HPLC unidentified peaks SOp B·E 5,9 u.d.
7.2t1.9
6.8 0.6
15 18 10
• p < 0.05 vs. Sop, no HPlC .. p < 0.05 vs.B-E, no HPLC These results show that Ang II levels quantified by direct RIA in plasma extracts from pregnant women may be falsely high due to the presence ot unidentified componants Which can be separated by HPLC. Pre-extraction with phenylsilyl-silica rather than 018 cartridges reduces butdoes not eliminate theartifact, indicating thatHPlC may be essential tortheaccurate estimation ofAng II in pregnancy plasma.
Key Words: AI1glotflnsin II, pregnancy, HPLe, radIoimmunoassay
BroiIl Kidney
AneiolCns;nQeen Kidney Liver
.lll Kidney
Liver HS 4.5iO.9 9.7i1.4 6,6:1:0.3 9.7±1.3 1O,1±2.0 LS 12.5±2.7* 12.5tI.9t 9.9i0.3 t 7.1±0.5t 13.8±1.8t VEH 9,4±1.3 6.ltO.9 3.4iO.6 3.6±O,7 1O,9±1.l AnglI 7.0±1.8§ 6.0tO.2 3.7tO.7 4.4±O, 3 W.?t!.! VEH I.9±O.2 7.0±0.9 4.8tO.2 1O,O±O.6 CAPT 6.5iO.3* 8.O±O.S 5.3±0.3 9.9tO.8 meanS±SE;*",P
AJH-APRIL 1995-VOL.8, NO.4, PART 2
BI0
B9 PLASMA LEVELS OF POTASSIUM, ALDOSTERONE, RENIN, AND THE ALDOSTERONE/RENIN RATIO IN PATIENTS WITH 'AIDOSTERONE-PRODUCrNG ADENOMA: RElATION TO DIAGNOSIS AND BLOOD PRESSURE OUTCOME. C Masslen.sJmQn" C Ballaglla, G Chatelller, TT Guyene, PF Plouin. HOpilal Broussars and Ihe COMETE network, Paris, France. To evaluale diagnostic tests for aldosterone-producing adenoma (APA), we compared plasma levels of potassium (K), aldosterone, renin, and the aldoslerone/renln (NR) ratio In 60 patients with surgIcally-proven APA, 50 patients with essential hypertension, and 49 normal volunteers. We also studIed Indicators predictive of postoperative blood pressure (BP) outcome In APA patients (improvement: diastolic BPS105 mmHg and reduced by ~15%; normallzatlon: DBP<90 mmHg wllhout treatment). Sensitivities (se) and speclfi~ities (sp) were determined after threshold optimizatfon using ROC curves and we then compared the Youden ind:ces (se+sp-1) of the dlffereJll tests. Although mean K levels were lower in APA than in EH (p
Key Words:. aldosterone-producing adenoma, potassium, aldosterone/renin ratio, ROC curves.
DOES CHRONIC ESTROGEN ACT AS A CONVERTING ENZYME INHIBITOR IN POSTMENOPAUSAL CYNOMOLGOUS MONKEYS? KB Brosnihan, D Weddle, MS Anthony, and CM Ferrario*• Bowman Gray School of Medicine, Winston-Salem, NC. To determine the effects of estrogen or estrogen and
progestin on the renin-angiotensin system. forty-five surgically postmenopausal cynomolgus monkeys were given either a conjugated equine estrogen (Premarin, 166 /lgJday), alone or in combination with medroxprogesterone acetate (Cycrin, 650 Ilg/day) for 30 months, or left with no hormone replacement therapy. Animals were anesthetized with ketaminepentobarbital, and samples were taken for themeasurement of plasma renin activity (PRA), angiotensin converting enzyme (ACE) activity and angiotensin peptides [Ang I, Ang II, and Ang·(l-1)J. Chronic replacement therapy with estrogen resulted in a significant reduction in ACE (229 ± 8 vs 189 ± 10 nmol/ml/min, p < 0.05, untreated vs estrogen), whereas the combination therapy of estrogen and progestin significantly elevated PRA (11.1 ± 2.0 vs 32.8 ± 4.9 nglmllmin, untreated vs combined therapy). Both of these changes in processing enzymes observed during estrogen or the combination therapy resulted in significant increases in plasma Ang I levels [46.7 ± 12,5 pg/ml (untreated) vs 175.5 ± 65.9 pglml (estrogen) and 561.7 ± 373.6 pg/ml (combination therapy). These studies reveal that chronic estrogen replacement selectively reduces ACE activity, whereas the combination of estrogen and progestin augments PRA. Thu., hormonal replacement shifts the processing of angiotensin peptides, making available more of the immediate precursor of the biologically active angiotensin peptides, Key Words: reni~. angiotensin, estrogen, progestin ovariectomy
B11
B12
HIGH ANG II LEVELS IN PLASMA OF ~REGNANT WOMEN REDUCED AFTER HPLC: MULTIPLE .rANG II PEAKS DETECTED
REGULATION OF ATl RECEPTOR mRNA IN RAT TISSUES. ~*. CA Griffin. G Giacchelli, JP Vatentin. C Llorens-Cones. P Corvol, and M Scbambelan. University of California San Francisco. CA; University of Udine, Italy; and College de France, Paris. France. In theadult kidney, theATI angiotensin (Angll) rccepror suvtype predominates. To study regulation of ATl receptor subtype gene expression in the rat. we altered activity of the renin-angiotensin system by: I) ingestion of a low- (LS. 0.07% Nae) or high- (HS. 7.5%) salt chow for 14 days; 2) infusion of AnglI (200 ng/kg,lmin. Lp.) or the vehicle (VEH) for 7 days; treatment with an angiotensin converting enzyme inhibitor (eaptopril, 100 mg,ldl. in the drinking water) or vehicle for 7 days. Renin. angiotensinogen, and ATI mRNA levels were measured byslot-bIOI and Northern hybridization using cRNA probes. ATtaand ATtb mRNA were determined byRT· PCR In thepresence ofa cRNA internal standard. Renal renin. renal and hepatic angiotenslnogen, and hepatic ATI mRNA levels were all
A C Bragat, P August·, J Oacclebaudo", J E Sealey· Cardiovascular Center, Cornell University Medical College, New York, NY
In pregnancy, high angiotensin (Ang) II levels have been reported in relalion to the circulating levels 01 plasma renin. In this report we investigate whether immunoreactive (i,') Ang II levels differ when plasma is pra,axtracted with phanylsilyl-silica Bond·EIut (8-E) rathar than Ct8 Sep·Pak (S-P) cartridges and when theextract ispurified by HPLC. Plasma from 5 pregnant women wasextracted using B-E or Sop cartridges. The irAng II levels were diractly quantified byradioimmunoassay. Also, Ang II was isolated using Isocratlc reversed-phase HPLC (as described by Nussbarger st al)lollowed .,ltar15 minutes by a gradient otIncreasing methanol (see Ailas at al abstract), The true Ang " peak elutad after 6 minutas, butother unidentified irAng It peaks were detected during thegradient, after 26 minutes. irAng II levels expressed in pglml are as follows: HPLC Angll Sop B-E 1.5 2.2
noHPLC
s·p
8-E 2.7 14
12
15
12
5.6
4.9 11
2.2
5.8
22 33 11
1.3
17 41 20 60 20
7.6 :1:2.4
17 :t4.7
2.7 ±1.4
3211*
12
:1:8.3
:t2."
12 5.2
mean sem
HPLC unidentified peaks SOp B·E 5,9 u.d.
7.2t1.9
6.8 0.6
15 18 10
• p < 0.05 vs. Sop, no HPlC .. p < 0.05 vs.B-E, no HPLC These results show that Ang II levels quantified by direct RIA in plasma extracts from pregnant women may be falsely high due to the presence ot unidentified componants Which can be separated by HPLC. Pre-extraction with phenylsilyl-silica rather than 018 cartridges reduces butdoes not eliminate theartifact, indicating thatHPlC may be essential tortheaccurate estimation ofAng II in pregnancy plasma.
Key Words: AI1glotflnsin II, pregnancy, HPLe, radIoimmunoassay
BroiIl Kidney
AneiolCns;nQeen Kidney Liver
.lll Kidney
Liver HS 4.5iO.9 9.7i1.4 6,6:1:0.3 9.7±1.3 1O,1±2.0 LS 12.5±2.7* 12.5tI.9t 9.9i0.3 t 7.1±0.5t 13.8±1.8t VEH 9,4±1.3 6.ltO.9 3.4iO.6 3.6±O,7 1O,9±1.l AnglI 7.0±1.8§ 6.0tO.2 3.7tO.7 4.4±O, 3 W.?t!.! VEH I.9±O.2 7.0±0.9 4.8tO.2 1O,O±O.6 CAPT 6.5iO.3* 8.O±O.S 5.3±0.3 9.9tO.8 meanS±SE;*",P