scholarly journals The role of thymoquinone as a potent antioxidant in ameliorating the neurotoxic effect of sodium arsenate in female rat

2017 ◽  
Vol 4 (3) ◽  
pp. 160-167 ◽  
Author(s):  
Rami B. Kassab ◽  
Rehab E. El-Hennamy
Keyword(s):  
Female Rat ◽  
Neurotoxic Effect ◽  
Sodium Arsenate

POSSIBLE ROLE OF 5α-ANDROSTANE-3α,17β-DIOL IN THE CONTROL OF FOLLICLE-STIMULATING HORMONE SECRETION IN THE IMMATURE FEMALE RAT

1982 ◽  
Vol 92 (1) ◽  
pp. 37-42 ◽  
Author(s):  
H. M. A. MEIJS-ROELOFS ◽  
P. KRAMER ◽  
L. GRIBLING-HEGGE
Keyword(s):  
Inhibitory Action ◽  
Combined Treatment ◽  
Hormone Secretion ◽  
Inhibitory Effect ◽  
Ovariectomized Rats ◽  
Female Rat ◽  
Immature Rat ◽  
Rat Strain ◽  
Intact Rats

A possible role of 5α-androstane-3α,17β-diol (3α-androstanediol) in the control of FSH secretion was studied at various ages in ovariectomized rats. In the rat strain used, vaginal opening, coincident with first ovulation, generally occurs between 37 and 42 days of age. If 3α-androstanediol alone was given as an ovarian substitute, an inhibitory effect on FSH release was evident with all three doses tested (50, 100, 300 μg/100 g body wt) between 13 and 30 days of age; at 33–35 days of age only the 300 μg dose caused some inhibition of FSH release. Results were more complex if 3α-androstanediol was given in combined treatment with oestradiol and progesterone. Given with progesterone, 3α-androstanediol showed a synergistic inhibitory action on FSH release between 20 and 30 days of age. However, when 3α-androstanediol was combined with oestradiol a clear decrease in effect, as compared to the effect of oestradiol alone, was found between 20 and 30 days of age. Also the effect of combined oestradiol and progesterone treatment was greater than the effect of combined treatment with oestradiol, progesterone and 3α-androstanediol. At all ages after day 20 none of the steroid combinations tested was capable of maintaining FSH levels in ovariectomized rats similar to those in intact rats. It is concluded that 3α-androstanediol might play a role in the control of FSH secretion in the immature rat, but after day 20 the potentially inhibitory action of 3α-androstanediol on FSH secretion is limited in the presence of oestradiol.

Abstract P040: Role of 20-HETE in Elevated Blood Pressure in Hyperandrogenemic Female Rats, a Model of Polycystic Ovarian Syndrome

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Chetan N Patil ◽  
Carolina Dalmasso ◽  
Rodrigo O Maranon ◽  
Huimin Zhang ◽  
Richard J Roman ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Polycystic Ovary ◽  
Premenopausal Women ◽  
Female Rats ◽  
Elevated Blood Pressure ◽  
Female Rat ◽  
Elevated Blood ◽  
Reproductive Disorder ◽  
Consomic Strain

Polycystic ovary syndrome (PCOS) is the most common reproductive disorder in premenopausal women, is characterized by hyperandrogenemia, metabolic syndrome and inflammation. They also exhibit elevated blood pressure (BP) but may not be treated since they do not meet the criteria for hypertension (BP>130/90 mm Hg). We have characterized a female rat model of hyperandrogenemia (HAF) using dihydrotestosterone (DHT) that mimics many characteristics of women with PCOS. In the present study we tested the hypothesis that androgen-induced upregulation of the cytochrome P450 4A2 isoform (CYP4A2) and the formation of 20-hydroxyeicosatetraenoic acid (20-HETE) in renal microvasculature contributes to the elevated BP in HAF rats. Female rats of SS.5BN consomic strain (wild type) rats and CYP4A2-/- rats on this same background were implanted with DHT (7.5mg/90d) or placebo pellets (n=5-8/grp) beginning at 6 wks of age; pellets were changed every 85 d. At 14 wks of age, rats were implanted with radiotelemetry transmitters, and mean arterial pressure (MAP) was measured for 10 days. Endogenous 20-HETE levels were measured using LC-MS in renal microvessels isolated using an Evans Blue sieving technique. DHT-treated HAF-SS.5BN rats had significantly higher MAP compared to placebo-SS.5BN (128±6 vs. 104±1 mmHg, p<0.004). In contrast, HAF-CYP4A2-/- rats had no change in MAP compared to placebo-CYP4A2-/- controls (120±4 vs 118±3 mmHg, p=NS). Endogenous 20-HETE levels in renal microvessels of HAF-SS.5BN rats were significantly increased compared to Placebo-SS.5BN (2.27±0.91 vs. 0.32±0.037 pmol/mg, p<0.01). The 20-HETE levels were lower in CYP4A2-/- than SS.5BN but DHT in HAF-CYP4A2-/- had no effect on 20-HETE levels compared to Placebo- CYP4A2-/-. These results suggest that androgen-mediated upregulation of the expression of CYP4A2 and the production of 20-HETE in renal microvessels contribute to elevated BP in HAF rats. These data also suggest that methods to attenuate 20-HETE may provide a novel therapeutic to reduce BP in women with PCOS. Work supported by NIH RO1HL66072 and PO1HL51971.

Abstract 579: Increased Role of COX-derived Prostanoids in Regulating Ang II Induced Uterine Artery Contraction at Early Pregnancy in a Transgenic Model of Preeclampsia

Hypertension ◽  
2014 ◽  
Vol 64 (suppl_1) ◽  
Author(s):  
Victor M Pulgar ◽  
Liliya M Yamaleyeva ◽  
Jasmina Varagic ◽  
Carolynne M McGee ◽  
Michael Bader ◽  
...  
Keyword(s):  
Uterine Artery ◽  
Inhibitory Effect ◽  
Isometric Tension ◽  
Late Gestation ◽  
Female Rat ◽  
Ang Ii ◽  
Sprague Dawley ◽  
Vascular Control ◽  
Human Renin

The balance between vasodilatory and vasoconstrictor prostanoids contributes to vascular control during pregnancy. Alterations in this balance are involved in the development of hypertensive pregnancy. The transgenic female rat containing the human angiotensinogen (hAGN) gene mated with the male transgenic containing human renin (hREN) is a model of preeclampsia (TgA), and shows hypertension and proteinuria at late gestation. We investigated the role COX-derived mediators have on contractility of the uterine artery (UA) in TgA rats before the hypertensive phenotype develops. UA were isolated from transgenic TgA (n=9) and Sprague-Dawley (n=7) control rats at 7 days of gestation. UA were mounted in a wire myograph for determinations of isometric tension (DMT USA, 620M). Responses to acetylcholine (ACh), phenylephrine (Phe) and sodium nitroprusside (SNP) were measured in control conditions and after preincubation with indomethacin (Indo, 10-5M). Data were fitted to a dose response curve, vasodilatation was expressed as percent of pre-constriction and sensitivity as pD2 (pD2= -Log [EC50]). Responses to ACh reached similar maximal relaxations (64±8 vs 75±6%, p>0.05), and an increased contraction in TgA UA at ACh >10μM (p<0.05) was eliminated by Indo. Contraction to Phe was similar in both groups with an inhibitory effect of Indo on TgA UA (p<0.05). Relaxation to SNP was lower in TgA vs SD UA (92±2 vs 74±5%, p<0.05), this difference was abolished by Indo. Thus, inhibition of COX enzymes had a greater effect on TgA UA suggesting an imbalance towards an increased prostanoids-derived constrictor tone in TgA UA. This imbalance appears before the hypertensive phenotype is established.

The Role of the Bed Nucleus of the Stria Terminalis in Stress-Induced Inhibition of Pulsatile Luteinising Hormone Secretion in the Female Rat

2010 ◽  
Vol 23 (1) ◽  
pp. 3-11 ◽  
Author(s):  
X. F. Li ◽  
Y. S. Lin ◽  
J. S. Kinsey-Jones ◽  
S. R. Milligan ◽  
S. L. Lightman ◽  
...  
Keyword(s):  
Luteinising Hormone ◽  
Hormone Secretion ◽  
Stria Terminalis ◽  
Female Rat ◽  
Bed Nucleus
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