Relationship between male hormonal status, Bezold–Jarisch reflex function, and ACE activity (cardiac and plasmatic)

2016 ◽  
Vol 94 (2) ◽  
pp. 231-236
Author(s):  
Otávio Arruda Heringer ◽  
Karla Oliveira dos Santos Cassaro ◽  
Nara Carolina Mateus Rabello Barbosa ◽  
Girlandia Alexandre Brasil ◽  
Andrews Marques do Nascimento ◽  
...  
Keyword(s):  
Negative Relationship ◽  
Morphometric Parameters ◽  
Male Rat ◽  
Hormonal Status ◽  
Hemodynamic Parameters ◽  
Converting Enzyme ◽  
Testosterone Levels ◽  
Cardiovascular Hemodynamics ◽  
17Β Estradiol ◽  
Ace Activity

The negative relationship between androgens and the Bezold–Jarisch reflex (BJR) has been demonstrated, but no studies evaluated the physiological influence of testosterone on this reflex. We evaluated the influence of male rat castration on the BJR, cardiac morphometric parameters, and the plasmatic and the cardiac angiotensin converting enzyme (ACE) activity. After castration (CAS), the rats were divided into 24 and 72 h (CAS24H, CAS72H), and 7 and 21 days (CAS7D, CAS21D) groups. The BJR was studied by administering increasing doses of phenylbiguanide (PBG; 1.5–24 μg/kg) at different times after castration. Castration results in the following: (i) reduction in testosterone levels (SHAM: 238.7 ± 15.1; CAS24H: 9.0 ± 0.5; CAS72H: 6.7 ± 0.4; CAS7D: 5.2 ± 0.2; and CAS21D: 2.2 ± 0.3 ng/dL; p < 0.05); (ii) no changes in 17β-estradiol; (iii) a reduced BJR sensitivity (PBG 6 μg/kg; SHAM: 77 ± 7; CAS24H: 63 ± 10; CAS72H: 55 ± 6; CAS7D: 54 ± 4; and CAS21D: 35 ± 2%; p < 0.01); (iv) a decrease in cardiac (SHAM: 107 ± 6; CAS24H: 92 ± 2; CAS72H: 82 ± 3; CAS7D: 54 ± 3; and CAS21D: 43 ± 4%; p < 0.05) and plasmatic (SHAM: 135 ± 8; CAS24H: 102 ± 5; CAS72H: 99 ± 3; CAS7D: 89 ± 4; and CAS21D: 56 ± 6%; p < 0.05) ACE activity. No changes were observed in cardiac morphometry and hemodynamic parameters. Therefore, castration leads to decrease in testosterone levels as early as 24 h, reduction in ACE activity and loss of BJR sensitivity 7 days after castration. The loss of BJR sensitivity was not related to cardiac morphometric changes and cardiovascular hemodynamics.

17β-Estradiol downregulates tissue angiotensin-converting enzyme and ANG II type 1 receptor in female rats

2005 ◽  
Vol 288 (3) ◽  
pp. R759-R766 ◽  
Author(s):  
Stephanie A. Dean ◽  
Junhui Tan ◽  
Edward R. O'Brien ◽  
Frans H. H. Leenen
Keyword(s):  
Angiotensin Converting Enzyme ◽  
Abdominal Aorta ◽  
Female Rats ◽  
Ang Ii ◽  
Converting Enzyme ◽  
Ovx Rats ◽  
17Β Estradiol ◽  
Ace Activity ◽  
Critical Components

Estrogens have been implicated in both worsening and protecting from cardiovascular disease. The effects of 17β-estradiol (E2) on the cardiovascular system may be mediated, at least in part, by its modulation of local tissue renin-angiotensin systems (RAS). We assessed two critical components, angiotensin-converting enzyme (ACE) and ANG II type 1 receptor (AT1R), in the heart, lung, abdominal aorta, adrenal, kidney, and brain in four groups of female Wistar rats ( n = 5–6/group): 1) sham ovariectomized, 2) ovariectomized (OVX) treated with subcutaneous vehicle, 3) OVX treated with 25 μg/day (regular) E2 subcutaneously, and 4) OVX treated with 250 μg/day (high) subcutaneous E2 for 2 or 5 wk. After 2 wk, plasma ACE activity was not altered by OVX, but it was 34–38% lower in OVX + regular E2 and OVX + high E2 rats compared with sham OVX rats, and these decreases were no longer present after 5 wk. After 5 wk, OVX alone increased ACE activity and binding densities, and AT1R binding densities by 15–100% in right ventricle, left ventricle (LV), kidney, lung, abdominal aorta, adrenal and several cardiovascular regulatory nuclei in the brain. These effects were, for the most part, prevented by regular E2 replacement and were reversed to decreases by high E2 treatment. This regulation of tissue ACE and AT1R is significant as the activity of these tissue RAS contributes to the pathogenesis and/or progression of hypertension, atherosclerosis, and LV remodeling after myocardial infarction.

scholarly journals Investigation of Chlorella pyrenoidosa Protein as a Source of Novel Angiotensin I-Converting Enzyme (ACE) and Dipeptidyl Peptidase-IV (DPP-IV) Inhibitory Peptides

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1624
Author(s):  
Yuchen Li ◽  
Gilda Aiello ◽  
Enrico Mario Alessandro Fassi ◽  
Giovanna Boschin ◽  
Martina Bartolomei ◽  
...  
Keyword(s):  
Chlorella Pyrenoidosa ◽  
Cellular Level ◽  
Potential Interaction ◽  
Converting Enzyme ◽  
Inhibitory Peptides ◽  
Angiotensin I Converting Enzyme ◽  
Dpp Iv ◽  
Ace Activity ◽  
The Stability

Chlorella pyrenoidosa (C. pyrenoidosa) is a microalgae species with a remarkably high protein content that may potentially become a source of hypotensive and hypoglycemic peptides. In this study, C. pyrenoidosa proteins were extracted and hydrolyzed overnight with pepsin and trypsin with final degrees of hydrolysis of 18.7% and 35.5%, respectively. By LC-MS/MS, 47 valid peptides were identified in the peptic hydrolysate (CP) and 66 in the tryptic one (CT). At the concentration of 1.0 mg/mL, CP and CT hydrolysates inhibit in vitro the angiotensin-converting enzyme (ACE) activity by 84.2 ± 0.37% and 78.6 ± 1.7%, respectively, whereas, tested at cellular level at the concentration of 5.0 mg/mL, they reduce the ACE activity by 61.5 ± 7.7% and 69.9 ± 0.8%, respectively. At the concentration of 5.0 mg/mL, they decrease in vitro the DPP-IV activity by 63.7% and 69.6% and in Caco-2 cells by 38.4% and 42.5%, respectively. Short peptides (≤10 amino acids) were selected for investigating the potential interaction with ACE and DPP-IV by using molecular modeling approaches and four peptides were predicted to block both enzymes. Finally, the stability of these peptides was investigated against gastrointestinal digestion.

Anti-Hypertensive Effect of Water Extract of Danshen on Renovascular Hypertension Through Inhibition of the Renin Angiotensin System

2002 ◽  
Vol 30 (01) ◽  
pp. 87-93 ◽  
Author(s):  
Dae Gill Kang ◽  
Yong Gab Yun ◽  
Jang Hyun Ryoo ◽  
Ho Sub Lee
Keyword(s):  
Plasma Concentration ◽  
Water Extract ◽  
Renin Angiotensin System ◽  
Plasma Renin ◽  
Dependent Manner ◽  
Converting Enzyme ◽  
Angiotensin System ◽  
Renin Angiotensin ◽  
Ace Activity ◽  
Dose Dependent

A study was designed to elucidate the mechanism of anti-hypertensive effects of Danshen in the two-kidney, one clip (2K1C) Goldblatt renovascular hypertensive model, which is the renin-angiotensin system (RAS)-dependent hypertensive model. We investigated the effects of water extracts of Danshen on the angiotensin converting enzyme (ACE) activities, systolic blood pressure (SBP), and hormone levels in the plasma of 2K1C rats. ACE activity was inhibited by the addition of Danshen extract in a dose-dependent manner. SBP was decreased significantly after administration of Danshen extract in 2K1C, whereas plasma renin activity (PRA) was not changed. The plasma concentration of aldosterone (PAC) was decreased significantly in 2K1C group administered with Danshen extract, whereas the plasma concentration of ANP was increased by administration of Danshen extract for three weeks. These results suggest that Danshen has an anti-hypertensive effect through the inhibition of ACE, an essential regulatory enzyme of RAS.

scholarly journals Nandrolone increases angiotensin-I converting enzyme activity in rats tendons

2015 ◽  
Vol 21 (3) ◽  
pp. 173-177 ◽  
Author(s):  
Rita de Cassia Marqueti ◽  
Nara Yumi Hashimoto ◽  
João Luiz Quaglioti Durigan ◽  
Lívia Larissa Batista e Silva ◽  
Jeeser Alves de Almeida ◽  
...  
Keyword(s):  
Training Session ◽  
Renin Angiotensin System ◽  
Tissue Growth ◽  
Control Group ◽  
Activity Levels ◽  
Converting Enzyme ◽  
Angiotensin I ◽  
Angiotensin I Converting Enzyme ◽  
Tendon Adaptation ◽  
Ace Activity

INTRODUCTION: The renin-angiotensin system (RAS) has been associated with several biological processes of the human body, regulating, among others blood pressure and water and electrolytes balance. Moreover, RAS also regulates connective tissue growth. Recently, studies have shown that the use of nandrolone modifies the angiotensin-I converting enzyme (ACE) activity and increases collagen deposition in the heart. OBJECTIVE: The aim of study was to evaluate the Angiotensin-I converting enzyme (ACE) activity in the superficial flexor tendon (SFT) and in serum after load exercise in combination with anabolic androgenic steroid (AAS) administration after training session and six weeks of detraining. METHODS: Forty-eight Wistar rats were used into two groups (G1 and G2) subdivided into four subgroups: Sedentary (S); trained (T); AAS-treated (Deca-Durabolin(r), 5mg/kg, twice a week) sedentary rats (AAS) and AAS-treated and trained animals (AAST). Trained groups performed jumps in water: four series of 10 jumps each, followed by a 30 sec interval between the series, for seven weeks. RESULTS: Training increased ACE activity in the SFT compared to the control group (p <0.05). Both AAS and AAST groups presented higher ACE activity levels (p < 0.05). The AAST increased the ACE activity only compared to the trained animals. Only the AAST group presented significant higher levels of ACE in the serum. In the G2 group, all experimental groups presented decreased ACE activity in the serum and in the tendon, as compared to the control group. CONCLUSION: This study indicates that AAS administration and its combination with exercise increased ACE activity of tendons. AAS abuse could compromise tendon adaptation causing maladaptive remodeling.

scholarly journals Antenatal betamethasone exposure is associated with lower ANG-(1–7) and increased ACE in the CSF of adult sheep

2013 ◽  
Vol 305 (7) ◽  
pp. R679-R688 ◽  
Author(s):  
Allyson C. Marshall ◽  
Hossam A. Shaltout ◽  
Nancy T. Pirro ◽  
James C. Rose ◽  
Debra I. Diz ◽  
...  
Keyword(s):  
Choroid Plexus ◽  
Lung Development ◽  
Fourth Ventricle ◽  
Baroreflex Sensitivity ◽  
Brush Border Membrane ◽  
Converting Enzyme ◽  
Angiotensin Converting Enzyme 2 ◽  
Ace Activity ◽  
And Control

Antenatal betamethasone (BM) therapy accelerates lung development in preterm infants but may induce early programming events with long-term cardiovascular consequences. To elucidate these events, we developed a model of programming whereby pregnant ewes are administered BM (2 doses of 0.17 mg/kg) or vehicle at the 80th day of gestation and offspring are delivered at term. BM-exposed (BMX) offspring develop elevated blood pressure; decreased baroreflex sensitivity; and alterations in the circulating, renal, and brain renin-angiotensin systems (RAS) by 6 mo of age. We compared components of the choroid plexus fourth ventricle (ChP4) and cerebral spinal fluid (CSF) RAS between control and BMX male offspring at 6 mo of age. In the choroid plexus, high-molecular-weight renin protein and ANG I-intact angiotensinogen were unchanged between BMX and control animals. Angiotensin-converting enzyme 2 (ACE2) activity was threefold higher than either neprilysin (NEP) or angiotensin 1-converting enzyme (ACE) in control and BMX animals. Moreover, all three enzymes were equally enriched by approximately 2.5-fold in ChP4 brush-border membrane preparations. CSF ANG-(1–7) levels were significantly lower in BMX animals (351.8 ± 76.8 vs. 77.5 ± 29.7 fmol/mg; P < 0.05) and ACE activity was significantly higher (6.6 ± 0.5 vs. 8.9 ± 0.5 fmol·min−1·ml−1; P < 0.05), whereas ACE2 and NEP activities were below measurable limits. A thiol-sensitive peptidase contributed to the majority of ANG-(1–7) metabolism in the CSF, with higher activity in BMX animals. We conclude that in utero BM exposure alters CSF but not ChP RAS components, resulting in lower ANG-(1–7) levels in exposed animals.

SHORT-TERM EFFECTS OF COPULATION, HUMAN CHORIONIC GONADOTROPHIN INJECTION AND NON-TACTILE ASSOCIATION WITH A FEMALE ON TESTOSTERONE LEVELS IN THE MALE RAT

1974 ◽  
Vol 60 (3) ◽  
pp. 429-439 ◽  
Author(s):  
K. PURVIS ◽  
N. B. HAYNES
Keyword(s):  
Chorionic Gonadotrophin ◽  
Human Chorionic Gonadotrophin ◽  
Physical Contact ◽  
Male Rats ◽  
Male Rat ◽  
Plasma Testosterone ◽  
Short Term ◽  
Testosterone Levels ◽  
Peripheral Plasma ◽  
First Contact

SUMMARY Peripheral plasma testosterone levels in the male rat were increased above control levels 5 min after the first intromission with an oestrous female, or 8–10 min after first contact with the female. The levels remained raised for at least 30 min if copulation was allowed to continue. Intravenous injection of human chorionic gonadotrophin resulted in an increased peripheral concentration of plasma testosterone after 10–15 min and an increase of testosterone content of the testis 5–10 min after injection, indicating that the rat testis has a potential to respond rapidly to gonadotrophin. The results suggested that if the testosterone surge during copulation was gonadotrophin-dependent, it was initiated before the first intromission. Indeed, plasma testosterone levels were raised in male rats 5 min after being placed in the proximity of oestrous females but not allowed physical contact.

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