Rat proximal NHE3 adapts to chronic acid-base disorders but not to chronic changes in dietary NaCl intake

2002 ◽  
Vol 282 (5) ◽  
pp. F835-F843 ◽  
Author(s):  
Dominique Eladari ◽  
Françoise Leviel ◽  
Françoise Pezy ◽  
Michel Paillard ◽  
Régine Chambrey
Keyword(s):  
Initial Rate ◽  
Apical Membrane ◽  
Membrane Vesicles ◽  
High Dose ◽  
Protein Abundance ◽  
Sprague Dawley ◽  
Acid Base ◽  
Sprague Dawley Rats ◽  
Apical Membrane Vesicles

In the proximal tubule, the apical Na+/H+ exchanger identified as NHE3 mediates most NaCl and NaHCO3 absorption. The purpose of this study was to analyze the long-term regulation of NHE3 during alkalosis induced by dietary NaHCO3 loading and changes in NaCl intake. Sprague-Dawley rats exposed to a low-NaCl, high-NaCl, or NaHCO3 diet for 6 days were studied. Renal cortical apical membrane vesicles (AMV) were prepared from treated and normal rats. Na+/H+ exchange was assayed as the initial rate of 22Na+ uptake in the presence of an outward H+ gradient. 22Na+uptake measured in the presence of high-dose 5-( N-ethyl- N-isopropyl) amiloride was not different among models. Changes in NaCl intake did not affect NHE3 activity, whereas NaHCO3 loading inhibited22Na+ uptake by 30%. AMV NHE3 protein abundance assessed by Western blot analysis was unaffected during changes in NaCl intake. During NaHCO3 loading, NHE3 protein abundance was decreased by 65%. We conclude that proximal NHE3 adapts to chronic metabolic acid-base disorders but not to changes in dietary NaCl intake.

Differential regulation of cholera toxin-inhibited Na-H exchange isoforms by butyrate in rat ileum

2007 ◽  
Vol 293 (4) ◽  
pp. G857-G863 ◽  
Author(s):  
Sandeep B. Subramanya ◽  
Vazhaikkurichi M. Rajendran ◽  
Pugazhendhi Srinivasan ◽  
Navalpur S. Nanda Kumar ◽  
Balakrishnan S. Ramakrishna ◽  
...  
Keyword(s):  
Protein Expression ◽  
Cholera Toxin ◽  
Apical Membrane ◽  
Membrane Vesicles ◽  
Ileal Loop ◽  
Camp Content ◽  
Nhe Isoforms ◽  
Apical Membrane Vesicles

Electroneutral Na absorption occurs in the intestine via sodium-hydrogen exchanger (NHE) isoforms NHE2 and NHE3. Bicarbonate and butyrate both stimulate electroneutral Na absorption through NHE. Bicarbonate- but not butyrate-dependent Na absorption is inhibited by cholera toxin (CT). Long-term exposure to butyrate also influences expression of apical membrane proteins in epithelial cells. These studies investigated the effects of short- and long-term in vivo exposure to butyrate on apical membrane NHE and mRNA, protein expression, and activity in rat ileal epithelium that had been exposed to CT. Ileal loops were exposed to CT in vivo for 5 h and apical membrane vesicles were isolated. 22Na uptake was measured by using the inhibitor HOE694 to identify NHE2 and NHE3 activity, and Western blot analyses were performed. CT reduced total NHE activity by 70% in apical membrane vesicles with inhibition of both NHE2 and NHE3. Reduced NHE3 activity and protein expression remained low following removal of CT but increased to control values following incubation of the ileal loop with butyrate for 2 h. In parallel there was a 40% decrease in CT-induced increase in cAMP content. In contrast, NHE2 activity partially increased following removal of CT and was further increased to control levels by butyrate. NHE2 protein expression did not parallel its activity. Neither NHE2 nor NHE3 mRNA content were affected by CT or butyrate. These results indicate that CT has varying effects on the two apical NHE isoforms, inhibiting NHE2 activity without altering its protein expression and reducing both NHE3 activity and protein expression. Butyrate restores both CT-inhibited NHE2 and NHE3 activities to normal levels but via different mechanisms.

scholarly journals Learning and Memory Effects of Neonatal Methamphetamine Exposure in Sprague-Dawley Rats: Test of the Role of Dopamine Receptors D1 in Mediating the Long-Term Effects

2019 ◽  
Vol 41 (1-2) ◽  
pp. 44-55 ◽  
Author(s):  
Sarah A. Jablonski ◽  
Michael T. Williams ◽  
Charles V. Vorhees
Keyword(s):  
Learning And Memory ◽  
Water Maze ◽  
High Dose ◽  
Sprague Dawley ◽  
Long Term Effects ◽  
Learning Deficits ◽  
Sprague Dawley Rats ◽  
Cincinnati Water Maze ◽  
Locomotor Deficits

Methamphetamine (MA) abuse is a worldwide issue that produces health and cognitive effects in the user. MA is abused by some women who then become pregnant and expose their developing child to the drug. Preclinical rodent models demonstrate cognitive deficits following developmental MA exposure, an effect observed in children exposed to MA in utero. To determine if the dopamine receptor D1 (DRD1) is involved in the learning and memory deficits following MA exposure, male Sprague-Dawley rats were treated 4 times daily at 2 h intervals with 0 (saline) or 10 mg/kg of MA from postnatal day (P)6–15, 30 min after 0.5, 1.0, or 2.0 mg/kg SCH23390. Cincinnati water maze testing began on P30, and the high dose of SCH23390 blocked the learning deficits induced by MA with no effect from the lower doses. Morris water maze (MWM) learning deficits following MA were not protected by SCH23390, although there was a non-dose dependent effect in the acquisition phase. Locomotor deficits induced by MA were reversed by all doses of SCH23390. There were no effects of MA on criterion to trial passive avoidance. Taken together, these data show that behaviors that are dependent on the striatum are better protected with the DRD1 antagonist during MA treatment than the hippocampally mediated spatial learning in the MWM. This suggests that multiple mechanisms exist for the deficits induced by neonatal MA administration.

scholarly journals Toxicological evaluation of chronic oral administration of Melissa officinalis hydro-ethanol extract in Sprague-Dawley rats

2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Mohammad Hashemnia ◽  
Farid Rezaei ◽  
Zahra Nikousefat ◽  
Maral Bahiraei
Keyword(s):  
Mononuclear Cells ◽  
Control Group ◽  
High Dose ◽  
Alcoholic Extract ◽  
Sprague Dawley ◽  
Melissa Officinalis ◽  
Medicinal Uses ◽  
Sprague Dawley Rats ◽  
Term Administration

Melissa officinalis is a plant that has been widely used as an herbal medicine in many countries. Unfortunately, despite the prevalent medicinal uses of the plant, there are no reports on the possible toxic effects of M. officinalis. This study was designed to evaluate the effect of long-term administration of hydro-alcoholic extract of M. officinalis on some biochemical and hematological parameters and histopathology of organs. Thirty Sprague-Dawley rats were allocated to three equal groups. The animals in groups A and B received 600 and 1200 mg/kg M. officinalis extract, respectively, for 30 days. The rats in group C were given gavaged saline as control. The animals were euthanized at the end of experiment and the blood samples were collected for biochemical and hematology analysis. Additionally, appropriate tissue samples were collected from kidney, liver, spleen, heart and lung for light microscopic examination. M. officinalis caused a significant increase in the alanine aminotransferase level in the treated rats. Although the increase in creatine phosphokinase and lactate dehydrogenase levels were observed in group A and B, respectively, but there were no significant differences. A significant decrease was observed in the total protein and albumin concentrations in serum of treated rats as compared to the control group. The creatinine concentrations were significantly higher in the group B when compared to the other groups. There were no significant differences in cholesterol, triglyceride and urea concentrations between all groups of rats. The main histopathologic findings in the liver were included hepatocyte degeneration, congestion and dilation of sinusoids, proliferation of bile ducts and infiltration of mononuclear cells around the portal area. Histopathologic examination of the kidneys showed a tubular degeneration and necrosis, tubular and glomerular atrophy and congestion. These lesions were more prominent in the high dose treated rats. The findings suggest that long-term administration of M. officinalis extract even at low doses induces hepatic and renal lesions in rats.

scholarly journals Antidepressant-Like Effect of Lipid Extract ofChanna striatusin Postpartum Model of Depression in Rats

2017 ◽  
Vol 2017 ◽  
pp. 1-15 ◽  
Author(s):  
Mohamed Saleem Abdul Shukkoor ◽  
Mohamad Taufik Hidayat Bin Baharuldin ◽  
Abdul Manan Mat Jais ◽  
Mohamad Aris Mohamad Moklas ◽  
Sharida Fakurazi ◽  
...  
Keyword(s):  
Postpartum Period ◽  
Estradiol Benzoate ◽  
Plasma Corticosterone ◽  
Positive Control ◽  
Lipid Extract ◽  
High Dose ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Malay Population ◽  
Swimming Test

Postpartum depression affects 15% of women.Channa striatus, a freshwater fish, is consumed in local Malay population as a rejuvenating diet during postpartum period. This study evaluated the antidepressant-like effect of lipid extract ofC. striatusfillet and its mechanism of action in female Sprague-Dawley rats in postpartum model of depression. The rats were ovariectomized and treated with high dose of progesterone and estradiol benzoate for 23 days to have hormone-simulated pregnancy. The day 24 and afterwards were considered as the postpartum period. During the postpartum period, lipid extract was administered at 125, 250, and 500 mg/kg through intraperitoneal route for 15 days. Fluoxetine (10 mg/kg) was used as the positive control. On postpartum day 15, the animals were tested in forced swimming test (FST) and open field test (OFT) followed by biochemical analysis. Withdrawal of hormone administration during the postpartum period induced depressive-like behavior in FST. Administration of lipid extract reversed that depressive-like behavior at 125, 250, and 500 mg/kg in FST. In OFT, it decreased the exploratory activity. The mechanism of the antidepressant-like effect may be mediated through the decrease in plasma corticosterone, increase in plasma oxytocin, and decrease in nuclear factor-kappa B in prefrontal cortex of rats.

Long-term exposure of Sprague Dawley rats to 20 kHz triangular magnetic fields

2006 ◽  
Vol 82 (4) ◽  
pp. 285-291 ◽  
Author(s):  
H. J. Lee ◽  
S. H. Kim ◽  
S. Y. Choi ◽  
Y. M. Gimm ◽  
J. K. Pack ◽  
...  
Keyword(s):  
Magnetic Fields ◽  
Sprague Dawley ◽  
Sprague Dawley Rats

Ultrastructural changes of Basolateral Amygdaloid nuclei in the Sprague Dawley rats brain following exposure to naphthalene balls

2021 ◽  
Vol 12 (2) ◽  
pp. 1272-1275
Author(s):  
Angu Bala Ganesh K S V ◽  
Sujeet Shekhar Sinha ◽  
Kesavi Durairaj ◽  
Abdul Sahabudeen K
Keyword(s):  
Structural Changes ◽  
Corn Oil ◽  
Chromatin Condensation ◽  
Ultrastructural Changes ◽  
High Dose ◽  
Model Group ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
The Brain ◽  
Amygdaloid Nuclei

Naphthalene is a bicyclic aromatic constituent commonly used in different domestic and marketable applications comprising soil fumigants, lavatory scent disks and mothballs. Accidentally, workers, children and animals are exposed to naphthalene mothballs, so there is a need to study the pathology behind this chemical toxicity. The current study was carried out to assess the ultra structural changes of basolateral amygdaloid nuclei in the Sprague Dawley rats brain in association to naphthalene toxicity. The toxicity model group was administered with naphthalene (200 and 400mg) using corn oil as a vehicle for 28 days. The post delayed toxicity of naphthalene high dose ingestion was also assessed in rats. After the experimental period, the brain tissue was processed to observe the ultra structural changes using a transmission electron microscope. The alterations in cell organelles, nuclei damage, mitochondrial swelling, chromatin condensation suggested naphthalene induced damage in the neurons of the basolateral amygdala of the brain in the toxicity model group. These experimental trials provide information about the alert of mothball usage in the home and identify risks linked with accidental exposure and misuse.

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