Uterine nitric oxide and prostaglandin E during embryonic implantation in non-insulin-dependent diabetic rats

1998 ◽  
Vol 10 (3) ◽  
pp. 217 ◽  
Author(s):  
V. Novaro ◽  
A. Jawerbaum ◽  
A. Faletti ◽  
M. A. F. Gimeno ◽  
E. T. González

In the process of embryo implantation in the rat, both nitric oxide and prostaglandins act as vascular and myometrial regulators. The aim of the present work was to evaluate the effect of diabetes on the synthesis of both agents during embryo implantation. In diabetic rats, uterine activity of the enzyme nitric oxide synthase and prostaglandin E production were increased during peri-implantation compared to the control group (P < 0·05 and P < 0·001, respectively). Both parameters showed a prolonged increase in temporal profile during peri-implantation days. Local production of nitric oxide and prostaglandin E in the implantation sites was higher in diabetic rats (P < 0·05), but the intersite : site ratio was similar to that of the control group. On the other hand, the implantation rate and the timing of the beginning of this process were not altered in the diabetic group. These results suggest that the vasoactive modulators of the implantation process, nitric oxide and prostaglandins, are increased in this diabetic pathology, and that this increase is probably functioning as a compensatory mechanism, so as to allow an unaltered rate of embryo implantation in this model. Extra keyword: diabetes mellitus.

1998 ◽  
Vol 10 (2) ◽  
pp. 191 ◽  
Author(s):  
Alicia Jawerbaum ◽  
Elida T. Gonzalez ◽  
Virginia Novaro ◽  
Alicia Faletti ◽  
Debora Sinner ◽  
...  

Embryonic development, prostaglandin E (PGE) generation and nitric oxide synthase (NOS) activity during organogenesis were evaluated in an experimental rat model of non-insulin- dependent diabetes (NIDD) generated by neonatal administration of streptozotocin. Gross malformations were detected in 5% of NIDD embryos and these embryos were all non-viable; in the other 95%, growth was retarded but no congenital abnormalities were found. Control embryos were all alive and not malformed. The NIDD 11-day embryos secreted more PGE into the incubation medium than did controls. The NO donor SIN–1 increased PGE production in both control and NIDD embryos. A NOS inhibitor (L-NMMA) reduced PGE generation in both experimental groups, suggesting a modulatory role of NO on embryonic PGE production. Activity of NOS was higher in NIDD 11-day embryos than in controls. Treatment in vivo of control and NIDD rats (Days 7–11 of gestation) with a NOS inhibitor (L-NAME; 5 mg kg-1 i.p.) reduced embryonic PGE production and induced a higher resorption rate and an increase in neural-tube defects. The results suggest that NO modulates PGE generation in the organogenetic embryo. In the NIDD model, overproduction of NO is observed, this NO probably enhancing embryonic PGE production. The relationship between PGE generation and the appearance of congenital abnormalities is discussed.


1998 ◽  
Vol 10 (2) ◽  
pp. 185 ◽  
Author(s):  
Alicia Jawerbaum ◽  
Elida T. Gonzalez ◽  
Virginia Novaro ◽  
Alicia Faletti ◽  
Martha A. F. Gimeno

Previous work described an increase in prostaglandin E (PGE) production by oocyte–cumulus complexes (OVA) obtained from non-insulin-dependent diabetic rats. More recently, it has been found that in control OVA nitric oxide (NO) mediates hCG-induced PGE secretion. To determine whether increases in PGE secretion by diabetic OVA are mediated by NO, the present study has evaluated the secretion of PGE by diabetic OVA, cultured in the absence or presence of hCG, NO donors (sodium nitroprusside (NP) and 3-morpholino-sydnonimine-hydrochloride (SIN–1)), and a NO synthase inhibitor (NG monomethyl-L-arginine; L-NMMA). hCG, NP and SIN–1 increased PGE secretion by diabetic OVA. L-NMMA did not modify basal secretion of PGE by control OVA but lowered PGE production in diabetic OVA to control values. L-NMMA prevented the hCG-induced PGE accumulation in control and diabetic OVA, and the quantities of PGE produced were similar to those of control OVA but lower than in diabetic OVA incubated in the absence of hCG. The effect of L-NMMA seems to be specific since NG monomethyl-D-arginine had no effect. NO synthase activity was higher in diabetic ovaries than in controls. The present results suggest that NO mediates the increased PGE production by diabetic OVA, probably a result of overproduction of NO.


Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Neeru M Sharma ◽  
Paras K Mishra ◽  
Kaushik P Patel

Activation of both renin-angiotensin- system (RAS) and sympathetic system are the primary etiologic events in the development of hypertension in diabetes mellitus (DM). However, the precise mechanisms for sympathetic activation in DM have not been elucidated. Our previous studies have demonstrated that neuronal nitric oxide (nNOS) expression and nitric oxide (NO) mediated inhibition of sympathetic nerve activity (SNA) is markedly reduced in the paraventricular nucleus (PVN) of streptozotocin-induced diabetic rats. We have further demonstrated that Angiotensin II (Ang II) via Ang II type 1 receptors (AT 1 R) modulates the expression of nNOS in the PVN, which augments sympathetic outflow. Here we hypothesized that DM-linked hypertension and cardiovascular dysregulation is due to the reduction in nNOS with the PVN. To test the hypothesis, we used Ins2 +/- Akita (a spontaneous, insulin dependent genetic diabetic murine model) which showed an increase in systolic blood pressure at the age of 14 weeks compared to corresponding C57BL/6J (WT) mice with concomitant decreased expression of nNOS (0.75±0.05 WT vs. 0.43±0.11* Akita) in the PVN. Further, Akita mice had increased expression of ACE (angiotensin converting enzyme) (WT 0.34±0.04 vs. Akita 0.58±0.05*) and AT 1 R (WT 0.29±0.09 vs. Akita 0.49±0.03*) and decreased expression of ACE2 (0.27±0.03 WT vs. 0.17±0.05* Akita) and Mas receptor (WT 0.77±0.07 vs. Akita 0.46±0.02*), suggesting an imbalance in the excitatory and protective arms of RAS. Moreover, we found increased protein levels of PIN (a protein inhibitor of nNOS, known to dissociate catalytically active nNOS dimers to monomers) (WT 0.71±0.09 vs. Akita 1.75±0.08) with 72 percent decrease in dimer/monomer ratio of nNOS (WT 0.19±0.0 vs. Akita 0.11±0.04) in the PVN of Akita mice. Taken together, our studies suggest that accumulation of PIN, mediated by activation of the excitatory arm of RAS, leads to a decrease in the active dimeric form of nNOS resulting in reduced NO causing an over-activation of the sympathetic drive, leading to hypertension in DM. 1


2003 ◽  
Vol 31 (02) ◽  
pp. 305-313 ◽  
Author(s):  
Mi-Hyeon Jang ◽  
Min-Chul Shin ◽  
Baek-Vin Lim ◽  
Hyun-Bae Kim ◽  
Young-Pyo Kim ◽  
...  

In the present study, the effect of acupuncture at Zusanli acupoint on nitric oxide synthase (NOS) expression in the hippocampus of streptozotocin (STZ)-induced diabetic rats was investigated via nicotinamide adenine dinucleotide phosphate-diaphorase (NADPH-d) histochemistry. Animals were divided into four groups: the control group, the nondiabetic and acupunctured group, the STZ-induced diabetes group, and the STZ-induced diabetes and acupunctured group. From the results, NADPH-d-positive neurons in the hippocampus were decreased in STZ-induced diabetic rats, while acupuncture increased NOS expression significantly under diabetic conditions. In the present study, it can be suggested that acupuncture treatment may modulate NOS activity in the hippocampus under diabetic conditions.


Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 429
Author(s):  
Jorge A. Bustamante-Andrade ◽  
César A. Meza-Herrera ◽  
Rafael Rodríguez-Martínez ◽  
Zurisaday Santos-Jimenez ◽  
Oscar Ángel-García ◽  
...  

The aim of this study was to evaluate the possible effect of two doses of hCG (100 and 300 IU) applied at two different times (7 and 14 d) after a fixed-time artificial insemination protocol (FTAI) upon some variables involved in the embryonic implantation rate in goats during the natural deep anestrous season (April, 25° north). The experimental units considered crossbred, multiparous, anovulatory goats (n = 69, Alpine, Saanen, Nubian x Criollo), with average body weight (43.6 ± 5.7 kg) and body condition score (1.86 ± 0.28 units) located in northern–semiarid Mexico (25° N, 103° W). Once the goat’s anestrus status was confirmed, goats were subjected to an estrus induction protocol. Upon estrus induction confirmation, goats (n = 61) were subjected to a FTAI procedure. Immediately after the FTAI, the goats were randomly distributed to five experimental groups: (1). G100-7 (n = 13) 100 IU, hCG 7 d post-FTAI, (2). G100-14 (n = 12) 100 IU hCG, 14 d post-FTAI, (3). G300-7 (n = 12) 300 IU, hCG, 7 d post-FTAI, (4). G300-14 (n = 12) 300 IU hCG 14 d post-FTAI, and (5). Control group, CONT (n = 12) 0.5 mL saline, 7 and 14 d post-FTAI. The response variables conception rate (39.36 ± 0.23), fertility rate (27.96%), prolificacy rate (1.1 ± 0.29 kids), ovulation rate (0.74 ± 0.20 corpus luteum) corpus luteum diameter (10.15 ± 0.59 mm), embryo number (1.58 ± 0.20), and embryo implantation rate (48.96%), did not differ between treatments. However, while the variables fecundity rate (67%), embryo efficiency index-1 (33.99 ± 0.20%), and embryo efficiency index-2 (27.94 ± 0.30%) were favored by the G300-14 treatment, the corpus luteum area was favored (p < 0.05) by both G300-7 (113.30 ± 0.19 mm2) and G300-14 (103.04 ± 0.17 mm2). Such reproductive strategy emerges as an interesting approach, not only to enhance the out-of-season reproductive outcomes, but also to boost one of the main rulers defining the global reproductive efficiency of a heard, namely, the embryo implantation efficiency.


2016 ◽  
Vol 96 (5) ◽  
pp. 796-807
Author(s):  
Yi-ping Chen ◽  
Qiang Liu ◽  
Dong Chen

To investigate the mechanism by which laser irradiation enhances the chilling tolerance of wheat seedlings, seeds were exposed to different treatments, and biochemical parameters were measured. Compared with the control group, chilling stress (CS) led to an increase in the concentrations of malondialdehyde (MDA) and H2O2, and decreases in the activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), glutathione reductase (GR), catalase (CAT), peroxidase (POD), and nitric oxide synthase (NOS), and the concentrations of nitric oxide (NO) and protein. Treatment with 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), sodium tungstate (ST), and NG-nitro-L-arginine methyl ester (L-NAME) followed by CS resulted in further increases in the concentrations of MDA and H2O2 and further decreases in the other parameters. However, treatment with PTIO, ST, and L-NAME followed by laser irradiation had the opposite effects on these parameters. When the seeds were treated with PTIO, ST, and L-NAME followed by laser and CS, the concentrations of MDA and H2O2 were significantly lower and the other parameters were higher than in the PTIO, ST, and L-NAME plus CS groups. These results suggest that CO2 laser irradiation enhances the chilling tolerance of wheat seedlings by stimulating endogenous NO synthesis.


1999 ◽  
Vol 91 (6) ◽  
pp. 1724-1724 ◽  
Author(s):  
Lars G. Fischer ◽  
Damian J. Horstman ◽  
Klaus Hahnenkamp ◽  
Nancy E. Kechner ◽  
George F. Rich

Background Nonselective nitric oxide synthase (NOS) inhibition has detrimental effects in sepsis because of inhibition of the physiologically important endothelial NOS (eNOS). The authors hypothesized that selective inducible NOS (iNOS) inhibition would maintain eNOS vasodilation but prevent acetylcholine- and bradykinin-mediated vasoconstriction caused by lipopolysaccharide-induced endothelial dysfunction. Methods Rats were administered intraperitoneal lipopolysaccharide (15 mg/kg) with and without the selective iNOS inhibitors L-N6-(1-iminoethyl)-lysine (L-NIL, 3 mg/kg), dexamethasone (1 mg/kg), or the nonselective NOS inhibitor Nomega-nitro-L-arginine methylester (L-NAME, 5 mg/kg). Six hours later, the lungs were isolated and pulmonary vasoreactivity was assessed with hypoxic vasoconstrictions (3% O2), acetylcholine (1 microg), Biochemical Engineering, and bradykinin (3 microg). In additional lipopolysaccharide experiments, L-NIL (10 microM) or 4-Diphenylacetoxy-N-methylpiperidine methiodide (4-DAMP, 100 microM), a selective muscarinic M3 antagonist, was added into the perfusate. Results Exhaled nitric oxide was higher in the lipopolysaccharide group (37.7+/-17.8 ppb) compared with the control group (0.4+/-0.7 ppb). L-NIL and dexamethasone decreased exhaled nitric oxide in lipopolysaccharide rats by 83 and 79%, respectively, whereas L-NAME had no effect. In control lungs, L-NAME significantly decreased acetylcholine- and bradykinin-induced vasodilation by 75% and increased hypoxic vasoconstrictions, whereas L-NIL and dexamethasone had no effect. In lipopolysaccharide lungs, acetylcholine and bradykinin both transiently increased the pulmonary artery pressure by 8.4+/-2.0 mmHg and 35.3+/-11.7 mmHg, respectively, immediately after vasodilation. L-NIL and dexamethasone both attenuated this vasoconstriction by 70%, whereas L-NAME did not. The acetylcholine vasoconstriction was dose-dependent (0.01-1.0 microg), unaffected by L-NIL added to the perfusate, and abolished by 4-DAMP. Conclusions In isolated perfused lungs, acetylcholine and bradykinin caused vasoconstriction in lipopolysaccharide-treated rats. This vasoconstriction was attenuated by administration of the iNOS inhibitor L-NIL but not with L-NAME. Furthermore, L-NIL administered with lipopolysaccharide preserved endothelium nitric oxide-dependent vasodilation, whereas L-NAME did not.


Nitric Oxide ◽  
2001 ◽  
Vol 5 (3) ◽  
pp. 252-260 ◽  
Author(s):  
Seiichi Oyadomari ◽  
Tomomi Gotoh ◽  
Kazumasa Aoyagi ◽  
Eiichi Araki ◽  
Motoaki Shichiri ◽  
...  

Hypertension ◽  
2000 ◽  
Vol 35 (2) ◽  
pp. 655-661 ◽  
Author(s):  
Radko Komers ◽  
Terry T. Oyama ◽  
Justin G. Chapman ◽  
Kristen M. Allison ◽  
Sharon Anderson

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