scholarly journals Pregnancy in rats is modulated by ganglionic cholinergic action

Reproduction ◽  
2006 ◽  
Vol 131 (6) ◽  
pp. 1151-1158 ◽  
Author(s):  
M Casais ◽  
S M Delgado ◽  
Z Sosa ◽  
A M Rastrilla

The control of ovarian steroidogenesis during pregnancy is mainly of endocrine origin. At present, there is little information about the influence of neural factors on the gestation physiology. The purpose of this work was to study the action of cholinergic agents in celiac ganglion upon the liberation of progesterone and ovarian androstenedione in the second half of pregnancy in rats. We used the ex vivo celiac ganglion–superior ovarian nerve–ovary integrated system (celiac ganglion–SON–ovary) that was incubated in buffer solution for 180 min, with the celiac ganglion and the ovary located in different compartments and linked by the SON. The results obtained indicate that the control values of ovarian androstenedione vary according to the pregnancy day analyzed. The addition of acetylcholine in ganglion decreased the liberation of both steroids on Day 15 whereas at the end of pregnancy it decreased the liberation of androstenedione without modifying progesterone. Due to the effect observed with atropine and hexametonium, acetylcholine action might occur through unspecific ganglionic pathways (Days 15 and 21) or through muscarinic ganglionic receptors (Days 19 and 20). Thus, we conclude that the cholinergic sympathetic system from the celiac ganglion might be a fine modulator of the pregnancy physiology.

2002 ◽  
Vol 22 (3) ◽  
pp. 342-352 ◽  
Author(s):  
Natalie Serkova ◽  
Paul Donohoe ◽  
Sven Gottschalk ◽  
Carsten Hainz ◽  
Claus U. Niemann ◽  
...  

The authors evaluated and compared the metabolic effects of cyclosporin A in the rat brain during normoxia and hypoxia/reperfusion. Ex vivo31P magnetic resonance spectroscopy experiments based on perfused rat brain slices showed that under normoxic conditions, 500 μg/L cyclosporin A significantly reduced mitochondrial energy metabolism (nucleotide triphosphate, 83 ± 9% of controls; phosphocreatine, 69 ± 9%) by inhibition of the Krebs cycle (glutamate, 77 ± 5%) and oxidative phosphorylation (NAD+, 65 ± 14%) associated with an increased generation of reactive oxygen species (285 ± 78% of control). However, the same cyclosporin A concentration (500 μg/L) was found to be the most efficient concentration to inhibit the hypoxia-induced mitochondrial release of Ca2+ in primary rat hippocampal cells with cytosolic Ca2+ concentrations not significantly different from normoxic controls. Addition of 500 μg/L cyclosporin A to the perfusion medium protected high-energy phosphate metabolism (nucleotide triphosphate, 11 ± 15% of control vs. 35 ± 9% with 500 μg/L cyclosporin A) and the intracellular pH (6.2 ± 0.1 control vs. 6.6 ± 0.1 with cyclosporin A) in rat brain slices during 30 minutes of hypoxia. Results indicate that cyclosporin A simultaneously decreases and protects cell glucose and energy metabolism. Whether the overall effect was a reduction or protection of cell energy metabolism depended on the concentrations of both oxygen and cyclosporin A in the buffer solution.


2020 ◽  
Author(s):  
Teena Rajan ◽  
Tania Read ◽  
Aya Abdalla ◽  
Bhavik Patel ◽  
Julie Macpherson

<i>Ex-vivo</i> pH profiling of the upper gastrointestinal (GI) tract (of a mouse) in both the absence and presence of pharmacological agents aimed at altering acid/bicarbonate production, is reported using an electrochemical pH probe, for the first time. Three pH electrodes were assessed for suitability using a GI tract biological mimic buffer solution containing 0.5 % mucin. These include a traditional glass pH probe, an iridium oxide (IrOx) coated electrode (both potentiometric) and a quinone (Q) surface-integrated boron doped diamond (BDD-Q) electrode (voltammetric). In mucin the timescale for both IrOx and glass to obtain stable pH readings was in the ~100’s of s, most likely due to mucin adsorption, in contrast to 6 s with the BDD-Q electrode. Both the glass and IrOx pH electrodes were also compromised on robustness due to fragility and delamination (IrOx); contact with the GI tissue was an experimental requirement. BDD-Q was deemed the most appropriate. Ten measurements were made along the GI tract, esophagus (1), stomach (5) and duodenum (4). Under untreated conditions (buffer only), the BDD-Q probe tracked the pH from neutral in the esophagus, to acidic in the stomach and rising to more alkaline in the duodenum. In the presence of omeprazole, a proton pump inhibitor, the body regions of the stomach exhibited elevated pH levels. Under melatonin treatment (a bicarbonate agonist and acid inhibitor), both the body of the stomach and the duodenum showed elevated pH levels. This study demonstrates the versatility of the BDD-Q pH electrode for real-time <i>ex-vivo</i> biological tissue measurements.


2020 ◽  
Author(s):  
Yong Beom Kim ◽  
Jae-Moon Choi ◽  
Chungon Park ◽  
Hey-Ran Choi ◽  
Junyong In ◽  
...  

Abstract Background: Sevoflurane affects on the A1 receptor in the central nervous system (CNS) and potentiates the action of neuromuscular blocking agents. In the present study, we investigated whether sevoflurane (SEVO) has the ability to potentiate the neuromuscular blocking effect of rocuronium and if the specific antagonist of adenosine receptor (SLV320) can reverse this effect. Methods: Phrenic nerve–hemidiaphragm tissue specimens were obtained from forty Sprague-Dawley (SD) rats. The specimens were immersed in an organ bath filled with Krebs buffer and stimulated by a train-of-four (TOF) pattern using indirect supramaximal stimulation at 20 s intervals. The specimens were randomly allocated to control, 2-chloroadenosine (CADO), SEVO, or SLV320+SEVO groups. In the CADO and SLV320+SEVO groups, CADO and SLV320 were added to the organ bath from the start to a concentration of 10 μM and 10 nM, respectively. We then proceeded with rocuronium-induced blockade of >95% depression of the first twitch tension of TOF (T1) and TOF ratio (TOFR). In the SEVO and SLV320+SEVO groups, SEVO was added to the Krebs buffer solution to concentration of 400 - 500 μM for 10 min. Sugammadex-induced T1 and TOFR recovery was monitored for 30 min until >95% of T1 and >0.9 of TOFR were confirmed, and the recovery pattern was compared by plotting these data. Results: There were no significant differences in the recovery pattern between the control and SEVO groups. However, there were significant differences between the SEVO and SLV320+SEVO groups. Conclusion: Sevoflurane potentiates of rocuronium-induced neuromuscular blocking effect and delays sugammadex-induced recovery from neuromuscular blockade.


Endocrinology ◽  
2018 ◽  
Vol 160 (1) ◽  
pp. 143-155 ◽  
Author(s):  
Sheng Wu ◽  
Ping Xue ◽  
Neile Grayson ◽  
Jeffrey S Bland ◽  
Andrew Wolfe

Abstract Polycystic ovary syndrome (PCOS) results from functional ovarian hyperandrogenism due to dysregulation of androgen secretion. Cultured theca cells from polycystic ovaries of women with the most common form of PCOS overexpress most androgen producing enzymes, particularly CYP450c17. In this study, a murine model was used of PCOS induced by chronic feeding with a high-fat diet that exhibits the reproductive, hyperandrogenic, and metabolic constellation of PCOS symptoms seen in women. Oral administration of KDT501, a hops-derived bitter taste receptor (Tas2R 108) isohumulone ligand resulted in resolution of PCOS-associated endocrine and metabolic disturbances and restored reproductive function. Pioglitazone, a PPARγ agonist, also improved metabolic and reproductive function, though not to the same degree as KDT501. Specifically, treatment of the murine PCOS model with KDT501 resulted in reduced testosterone and androstenedione levels in the absence of significant changes in LH or FSH, improved glucose tolerance and lipid metabolism, and reduced hepatic lipid infiltration and adiposity. There was significant improvement in estrous cyclicity and an increase in the number of ovarian corpora lutea, indicative of improved reproductive function after exposure to KDT501. Finally, ex vivo exposure of murine ovaries to KDT501 attenuated androgen production and ovarian expression of CYP450c17. Interestingly, the ovaries expressed Tas2R 108, suggesting a potential regulation of ovarian steroidogenesis through this chemosensory receptor family. In summary, a therapeutic strategy for PCOS possibly could include direct influences on ovarian steroidogenesis that are independent of gonadotrophic hormone regulation.


1991 ◽  
Vol 261 (4) ◽  
pp. H1317-H1323
Author(s):  
H. Schutte ◽  
S. Rosseau ◽  
D. Walmrath ◽  
F. Grimminger ◽  
C. Ernst ◽  
...  

Kinetics of polymorphonuclear leukocyte (PMN) lung passage were investigated in ex vivo isolated and ventilated left rabbit lungs, perfused with buffer solution at physiological flow rate. 111In-labeled PMNs of rabbit or human origin were injected into the pulmonary artery, and the first fraction of PMNs that rapidly passed the lung together with coinjected erythrocytes, was collected separately for external radioactivity counting. Washout of initially retained PMNs from the lung was monitored by use of a sodium-iodide detector. Recirculation of cells was avoided by insertion of a filter in the perfusion circuit. A fraction of 16.6 +/- 1.3% of rabbit PMNs rapidly passed the lung vasculature, followed by an exponential washout of initially retained PMNs [half-time (t50) of lung transit 8.1 +/- 0.6 min]. Slightly higher t50 (12.2 +/- 1.0 min) was obtained upon use of human PMNs. Reduction in flow by 50% caused a marked prolongation of PMN transit (t50 = 27.8 +/- 5.1 min), whereas increase in flow to 150% only insignificantly decreased t50. Rise in pulmonary venous pressure to 5 and 8 mmHg caused retardation of PMN lung transit (t50 = 15.3 +/- 0.6 and 31.6 +/- 3.6 min). Preincubation of PMNs with 2 ng/ml endotoxin for 1 h induced marked delay in PMN washout (t50 = 26.1 +/- 2.8 min). In conclusion, single-pass PMN kinetics in isolated lungs correspond to in vivo studies previously reported, thus allowing elucidation of PMN-endothelial interactions in an intact lung vasculature under standardized conditions.


2001 ◽  
Vol 170 (3) ◽  
pp. 575-584 ◽  
Author(s):  
M Casais ◽  
ZY Sosa ◽  
AM Rastrilla ◽  
LI Aguado

Most of the fibres that constitute the superior ovarian nerve (SON) originate at the neuronal bodies of the coeliac ganglion and innervate rat ovarian stroma cells. The purpose of this work was to study the part played by innervation on ovarian release of progesterone on day 15 and at the end of pregnancy in an integrated in vitro system known as the coeliac ganglion-SON-ovary system. We also investigated, in the same system, whether there is some kind of inter-relationship between the effect of adrenergic agents and LH on progesterone release on day 15 of pregnancy. The coeliac ganglion and the ovary were incubated in separate compartments, linked by the SON. The ovary was immersed in 2 ml buffer solution (ovarian compartment) and the coeliac ganglion was immersed in 2 ml of a different buffer solution (ganglion compartment). Under these conditions, the accumulation of progesterone in the ovarian compartment medium was used as an endpoint. Conditions were standardised on day 15 of pregnancy, when the decrease in the release of ovarian progesterone caused by non-specific stimulation on the ganglion with KCl (56 mM) demonstrated the functional integrity of the system. Neural influence was evaluated by the addition of adrenergic agents at a concentration of 10(-6)M to the coeliac ganglion. On day 15 of pregnancy, noradrenaline and propranolol increased progesterone release while phentolamine diminished it. The existence of ganglionic tone was assessed by analysing progesterone basal levels at different stages of pregnancy. The highest secretion of progesterone was found to take place on day 15, diminishing as pregnancy advanced. In addition, adrenergic neural participation was studied during the physiological luteolysis occurring at the end of pregnancy. Major findings were that noradrenaline increased ovarian accumulation of progesterone on day 19 and decreased it on day 20, while propranolol and phentolamine diminished progesterone release on both days. In additional studies, some neuroendocrine aspects were investigated at a peripheral level. The addition of LH only to the ovarian compartment did not affect progesterone secretion. However, when LH in the ovarian compartment was accompanied by noradrenaline, propranolol or phentolamine in the ganglion compartment, the release of progesterone decreased. It can be concluded that modifications of the neural state of the coeliac ganglion affect ovarian progesterone secretion and the physiology of pregnancy via the SON. The results may confirm that the coeliac ganglion-SON-ovary system provides a direct link between the autonomic nervous system and physiological events during pregnancy.


2019 ◽  
Vol 6 (3) ◽  
pp. 70 ◽  
Author(s):  
Samuel D. Salinas ◽  
Margaret M. Clark ◽  
Rouzbeh Amini

Since many soft tissues function in an isotonic in-vivo environment, it is expected that physiological osmolarity will be maintained when conducting experiments on these tissues ex-vivo. In this study, we aimed to examine how not adhering to such a practice may alter the mechanical response of the tricuspid valve (TV) anterior leaflet. Tissue specimens were immersed in deionized (DI) water prior to quantification of the stress–strain responses using an in-plane biaxial mechanical testing device. Following a two-hour immersion in DI water, the tissue thickness increased an average of 107.3% in the DI water group compared to only 6.8% in the control group, in which the tissue samples were submerged in an isotonic phosphate buffered saline solution for the same period of time. Tissue strains evaluated at 85 kPa revealed a significant reduction in the radial direction, from 34.8% to 20%, following immersion in DI water. However, no significant change was observed in the control group. Our study demonstrated the impact of a hypo-osmotic environment on the mechanical response of TV anterior leaflet. The imbalance in ions leads to water absorption in the valvular tissue that can alter its mechanical response. As such, in ex-vivo experiments for which the native mechanical response of the valves is important, using an isotonic buffer solution is essential.


2020 ◽  
Author(s):  
Teena Rajan ◽  
Tania Read ◽  
Aya Abdalla ◽  
Bhavik Patel ◽  
Julie Macpherson

<i>Ex-vivo</i> pH profiling of the upper gastrointestinal (GI) tract (of a mouse) in both the absence and presence of pharmacological agents aimed at altering acid/bicarbonate production, is reported using an electrochemical pH probe, for the first time. Three pH electrodes were assessed for suitability using a GI tract biological mimic buffer solution containing 0.5 % mucin. These include a traditional glass pH probe, an iridium oxide (IrOx) coated electrode (both potentiometric) and a quinone (Q) surface-integrated boron doped diamond (BDD-Q) electrode (voltammetric). In mucin the timescale for both IrOx and glass to obtain stable pH readings was in the ~100’s of s, most likely due to mucin adsorption, in contrast to 6 s with the BDD-Q electrode. Both the glass and IrOx pH electrodes were also compromised on robustness due to fragility and delamination (IrOx); contact with the GI tissue was an experimental requirement. BDD-Q was deemed the most appropriate. Ten measurements were made along the GI tract, esophagus (1), stomach (5) and duodenum (4). Under untreated conditions (buffer only), the BDD-Q probe tracked the pH from neutral in the esophagus, to acidic in the stomach and rising to more alkaline in the duodenum. In the presence of omeprazole, a proton pump inhibitor, the body regions of the stomach exhibited elevated pH levels. Under melatonin treatment (a bicarbonate agonist and acid inhibitor), both the body of the stomach and the duodenum showed elevated pH levels. This study demonstrates the versatility of the BDD-Q pH electrode for real-time <i>ex-vivo</i> biological tissue measurements.


Biomaterials ◽  
2015 ◽  
Vol 55 ◽  
pp. 64-83 ◽  
Author(s):  
Sumit Murab ◽  
Juhi Samal ◽  
Akshay Shrivastava ◽  
Alok Ranjan Ray ◽  
Abhay Pandit ◽  
...  

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