scholarly journals Brainstem glioma progression in juvenile and adult rats

2008 ◽  
Vol 109 (5) ◽  
pp. 849-855 ◽  
Author(s):  
Qing Liu ◽  
Ran Liu ◽  
Meghana V. Kashyap ◽  
Rajnee Agarwal ◽  
Xiang'en Shi ◽  
...  
Keyword(s):  
Survival Time ◽  
Growth Pattern ◽  
Age Groups ◽  
Brainstem Glioma ◽  
C6 Glioma Cells ◽  
Tumor Proliferation ◽  
Apoptotic Cells ◽  
Adult Rats ◽  
Young Rats ◽  
Glioma Model

Object Brainstem gliomas are common in children and have the worst prognosis of any brain tumor in this age group. On the other hand, brainstem gliomas are rare in adults, and the authors of some clinical studies have suggested that this lesion behaves differently in adults than in children. In the present study, the authors test an orthotopic C6 brainstem glioma model in juvenile and adult rats, and investigate the biological behavior of this lesion in the 2 age groups. Methods The C6 glioma cells were stereotactically implanted into the pons of juvenile or adult male rats. Neurological presentation and survival time were recorded. Tumor proliferation and the number of apoptotic cells in brainstem gliomas of young and adult rats were determined by immunohistochemical staining with Ki 67 and terminal deoxynucleotidyl transferase 2′-deoxyuridine 5′-triphosphate-mediated nick-end labeling assay. Results Striking differences in the onset of neurological signs, duration of symptoms, survival time, tumor growth pattern, tumor proliferation, and number of apoptotic cells were found between the gliomas in the 2 groups of rats. The lesions were relatively focal in adult rats but more diffuse in young rats. Furthermore, brainstem gliomas in adult rats were less proliferative and had more apoptotic cells than those in young rats. Conclusions The authors found that the C6 brainstem glioma model in young and adult rats closely imitates the course of brainstem glioma in humans both in neurological findings and histopathological characteristics. Their findings also suggest that the different growth pattern and invasiveness of these lesions in children compared with that in adults could be due to different cellular environments in the 2 age groups, and warrants further investigation into the difference in the host response to brainstem gliomas in children and adults.

Age-dependent activation of PKC isoforms by angiotensin II in the proximal nephron

2001 ◽  
Vol 281 (3) ◽  
pp. R861-R867 ◽  
Author(s):  
Dianne M. Boesch ◽  
Jeffrey L. Garvin
Keyword(s):  
Specific Binding ◽  
Age Groups ◽  
Proximal Tubules ◽  
Ang Ii ◽  
Fluid Absorption ◽  
Adult Rats ◽  
Young Rats ◽  
Age Related ◽  
Pkc Isoforms ◽  
Pkc Β

ANG II increases fluid absorption in proximal tubules from young rats more than those from adult rats. ANG II increases fluid absorption in the proximal nephron, in part, via activation of protein kinase C (PKC). However, it is unclear how age-related changes in ANG II-induced stimulation of the PKC cascade differ as an animal matures. We hypothesized that the response of the proximal nephron to ANG II decreases as rats mature due to a reduction in the amount and activation of PKC rather than a decrease in the number or affinity of ANG II receptors. Because PKC translocates from the cytosol to the membrane when activated, we first measured PKC activity in the soluble and particulate fractions of proximal tubule homogenates exposed to vehicle or 10−10 M ANG II from young (26 ± 1 days old) and adult rats (54 ± 1 days old). ANG II increased PKC activity to the same extent in homogenates from young rats (from 0.119 ± 0.017 to 0.146 ± 0.015 U/mg protein) ( P < 0.01) and adult rats (from 0.123 ± 0.020 to 0.156 ± 0.023 U/mg protein) ( P < 0.01). Total PKC activity did not differ between groups (0.166 ± 0.018 vs. 0.181 ± 0.023). We next investigated whether activation of the α-, β-, and γ-PKC isoforms differed by Western blot. In homogenates from young rats, ANG II significantly increased activated PKC-α from 40.2 ± 6.5 to 60.2 ± 9.5 arbitrary units (AU) ( P < 0.01) but had no effect in adult rats (46.1 ± 5.1 vs. 48.5 ± 8.2 AU). Similarly, ANG II increased activated PKC-γ in proximal tubules from young rats from 47.9 ± 13.2 to 65.6 ± 16.7 AU ( P < 0.01) but caused no change in adult rats. Activated PKC-β, however, increased significantly in homogenates from both age groups. Specifically, activated PKC-β increased from 8.6 ± 1.4 to 12.2 ± 2.1 AU ( P < 0.01) in homogenates from nine young rats and from 19.0 ± 5.5 to 25.1 ± 7.1 AU ( P < 0.01) in homogenates from 12 adult rats. ANG II did not alter the amount of soluble PKC-α, -β, and -γ significantly. The total amount of PKC-α and -γ did not differ between homogenates from young and adult rats, whereas the total amount of PKC-β was 59.7 ± 10.7 and 144.9 ± 41.8 AU taken from young and adult rats, respectively ( P < 0.05). Maximum specific binding and affinity of ANG II receptors were not significantly different between young and adult rats. We concluded that the primary PKC isoform activated by ANG II changes during maturation.

scholarly journals Competition among oxidizable substrates in brains of young and adult rats. Dissociated cells

1984 ◽  
Vol 219 (1) ◽  
pp. 131-135 ◽  
Author(s):  
L M Roeder ◽  
J T Tildon ◽  
D C Holman
Keyword(s):  
Plasma Membranes ◽  
Ketone Bodies ◽  
Age Groups ◽  
Cell Types ◽  
Adult Brain ◽  
Brain Cells ◽  
Adult Rats ◽  
Young Rats ◽  
Dissociated Cells ◽  
14Co2 Production

The rates of conversion of D-(-)-3-hydroxy[3-14C]butyrate, [3-14C]acetoacetate, [6-14C]glucose and [U-14C]glutamine into 14CO2 were measured in the presence and absence of alternative oxidizable substrates in intact dissociated cells from the brains of young and adult rats. When unlabelled glutamine was added to [6-14C]glucose or unlabelled glucose was added to [U-14C]glutamine, the rate of 14CO2 production was decreased in both young and adult rats. The rate of oxidation of 3-hydroxy[3-14C]butyrate was also decreased by the addition of unlabelled glutamine in both age groups, but in the reverse situation, i.e. unlabelled 3-hydroxybutyrate added to [U-14C]glutamine, only the brain cells from young rats were affected. No significant effects were seen when glutamine and acetoacetate were combined. The addition of either of the two ketone bodies to [6-14C]glucose markedly lowered the rate of 14CO2 production in young rats, but in the adult only 3-hydroxybutyrate was effective and the magnitude of decrease in the rate of [6-14C]glucose oxidation was much lower than in young animals. Unlabelled glucose decreased the rate of [3-14C]acetoacetate oxidation to a minor extent in brain cells from both age groups; when added to 3-hydroxy[3-14C]butyrate, glucose had no effect in young rats and greatly enhanced 14CO2 production in adult brain cells. Many of these patterns of substrate interaction in dissociated brain cells differ from those in whole homogenates; they may be a function of the plasma membranes and the role of a carrier-mediated transport system or a reflection of a difference in the population of cell types or subcellular organelles in these two preparations.

scholarly journals Hesperidin inhibits ovariectomized-induced osteopenia and shows differential effects on bone mass and strength in young and adult intact rats

2008 ◽  
Vol 104 (3) ◽  
pp. 648-654 ◽  
Author(s):  
M. N. Horcajada ◽  
V. Habauzit ◽  
A. Trzeciakiewicz ◽  
C. Morand ◽  
A. Gil-Izquierdo ◽  
...  
Keyword(s):  
Bone Loss ◽  
Bone Mass ◽  
Age Groups ◽  
Female Rats ◽  
Lipid Lowering ◽  
Mineral Density ◽  
Adult Rats ◽  
Young Rats ◽  
Ovx Rats ◽  
Intact Rats

The main aim of this study was to investigate the bone-sparing effect of hesperidin, one of the main flavonoid present in oranges, in two age groups of ovariectomized female rats, compared with their intact controls. Young (3 mo) and adult (6 mo) female Wistar rats were sham operated (SH) or ovariectomized (OVX) and then pair-fed for 90 days a casein-based diet supplemented or not with 0.5% hesperidin (Hp; n = 10/group). In older rats, Hp intake led to a partial inhibition of OVX-induced bone loss, whereas a complete inhibition was obtained in younger animals. At both ages, while plasma osteocalcin concentrations were unchanged, urinary excretion of deoxypyridinoline was reduced by Hp intake, suggesting that Hp was able to slow down bone resorption. Unexpectedly, in intact young rats, Hp consumption resulted in a significant increase in bone mineral density (BMD). Indeed, 6-mo-old HpSH rats had a similar BMD to 9-mo-old nontreated SH adult rats, suggesting an accelerated bone mass gain in the young rats. In contrast, in intact adult rats, Hp did not further increase BMD but did improve their bone strength. The results of this study show a protective effect of Hp on bone loss in OVX rats of both ages without uterine stimulation and accompanied by a lipid-lowering effect. The unexpected and intriguing findings obtained in intact rats showing improved BMD in young rats and improved femoral load in adult rats merit further investigation. The bone and lipid benefits of hesperidin make it an attractive dietary agent for the management of the health of postmenopausal women.

Developmental study of benzodiazepine effects on monosynaptic GABAA-mediated IPSPs of rat hippocampal neurons

1993 ◽  
Vol 70 (3) ◽  
pp. 1076-1085 ◽  
Author(s):  
C. Rovira ◽  
Y. Ben-Ari
Keyword(s):  
Hippocampal Neurons ◽  
Receptor Agonist ◽  
Hippocampal Slices ◽  
Pyramidal Cells ◽  
Developmental Study ◽  
Type I ◽  
Gamma Aminobutyric Acid ◽  
Adult Rats ◽  
Young Rats ◽  
In Cells

1. The effects of type I (BZ1) and type II (BZ2) benzodiazepine receptor ligands on monosynaptic gamma-aminobutyric acid (GABA)A-mediated inhibitory postsynaptic potentials (IPSPs) and on responses to exogenously applied GABA were studied using intracellular recordings from CA3 pyramidal cells of rat hippocampal slices taken at different postnatal stages [postnatal day 4 (P4)-P35)]. 2. The effects of midazolam, a BZ1 and BZ2 receptor agonist, were tested on the monosynaptic IPSPs at different stages. Monosynaptic, bicuculline-sensitive IPSPs were evoked by hilar stimulation in presence of alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) and N-methyl-D-aspartate (NMDA) antagonists [6-cyano-7-nitroquinoxaline-2,3-dione (10 microM) and D(-)2-amino-5-phosphonopentanoic acid (50 microM)]. Midazolam at 300 nM maximally increased the duration and amplitude of monosynaptic GABAA-mediated IPSPs in neurons from pups (P4-P6, n = 6) and young (P7-P12, n = 8) and adult (P25-P35, n = 9) rats. All the effects of midazolam on IPSPs were reversed by the antagonist Ro 15-1788 (10 microM). 3. The effect of midazolam was also tested on the response to exogenously applied GABA (5 mM) in the presence of tetrodotoxine [TTX (1 microM)]. In neurons from young rats (n = 9), midazolam (1 nM-1 microM) did not change the responses to exogenously applied GABA, whereas in adult rats (n = 8) midazolam maximally increased GABA currents at 30 nM. 4. The effect of zolpidem, a BZ1 receptor agonist, was tested on monosynaptic IPSPs and GABA currents at different stages. Zolpidem (10 nM-1 microM) was inactive in cells from young rats (n = 12). In neurons from adult rats, zolpidem maximally increased the duration and amplitude of the monosynaptic IPSPs at 300 nM (n = 5) and the amplitude of GABA current at 30-100 nM (n = 5). 5. Methyl-6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM) (300 nM), an inverse agonist of BZ1 and BZ2 receptors, decreased the amplitude and duration of monosynaptic IPSPs in neurons from pups (n = 3) and young (n = 4) and adult (n = 5) rats. In all cases, full recovery was obtained after exposure to R0 15-1788 (10 microM). DMCM (300 nM-10 microM) failed to reduce GABA responses in cells from young (n = 3) or adult (n = 7) rats. 6. Results indicate that the regulation by benzodiazepine of GABAA-mediated IPSPs varies with the developmental stage.(ABSTRACT TRUNCATED AT 400 WORDS)

Downregulation of renal vasopressin V2 receptor and aquaporin-2 expression parallels age-associated defects in urine concentration

2004 ◽  
Vol 287 (4) ◽  
pp. F797-F805 ◽  
Author(s):  
Ying Tian ◽  
Ryota Serino ◽  
Joseph G. Verbalis
Keyword(s):  
Collecting Duct ◽  
Water Channel ◽  
Age Groups ◽  
Urine Osmolality ◽  
Brown Norway ◽  
Water Restriction ◽  
Water Excretion ◽  
F1 Hybrid ◽  
Young Rats ◽  
Aquaporin 2

Renal concentrating ability is known to be impaired with aging. The antidiuretic hormone AVP plays an important role in renal water excretion by regulating the membrane insertion and abundance of the water channel aquaporin-2 (AQP2); this effect is primarily mediated via the V2 subtype of the AVP receptor (V2R). This study evaluated the hypothesis that decreased renal sensitivity to AVP, with subsequent altered renal AQP2 expression, contributes to the reduced urinary concentrating ability with aging. Our results show that under baseline conditions, urine osmolality is significantly lower in aged Fischer 344 and Brown-Norway F1 hybrid (F344BN) rats despite equivalent plasma AVP concentrations as in young rats. Levels of kidney V2R mRNA expression and AQP2 abundances were also significantly decreased in aged F344BN rats, as was AQP2 immunostaining in collecting duct cells. In response to moderate water restriction, urine osmolality increased by significantly lesser amounts in aged F344BN rats compared with young rats despite similar increases in plasma AVP levels. Moderate water restriction induced equivalent relative increases in renal AQP2 abundances in all age groups but resulted in significantly lower abundances in total kidney AQP2 protein in aged compared with young F344BN rats. These results therefore demonstrate a functional impairment of renal concentrating ability in aged F344BN rats that is not due to impaired secretion of AVP but rather appears to be related to impaired responsiveness of the kidney to AVP that is secondary, at least in part, to a downregulation of renal V2R expression and AQP2 abundance.

Functional and molecular characterization of NHE3 expression during ontogeny in rat jejunal epithelium

1997 ◽  
Vol 273 (6) ◽  
pp. C1937-C1946 ◽  
Author(s):  
James F. Collins ◽  
Hua Xu ◽  
Pawel R. Kiela ◽  
Jiamin Zeng ◽  
Fayez K. Ghishan
Keyword(s):  
Northern Blot ◽  
Polyclonal Antibodies ◽  
Membrane Vesicle ◽  
Age Groups ◽  
Fold Increase ◽  
Jejunal Mucosa ◽  
Mrna Levels ◽  
Adult Rats ◽  
Intestinal Brush Border Membrane ◽  
Protein Levels

Ontogenic changes occur in intestinal brush-border membrane vesicle (BBMV) Na+/H+exchange activity. The present studies were designed to investigate ontogenic changes in Na+/H+exchanger (NHE) isoform 3 in rat jejunum. pH-dependent Na+ uptake was assayed in four age groups of rats in the presence of 0, 50, or 800 μM HOE-694, a specific NHE inhibitor with differential sensitivities for NHE2 [inhibition constant ( K i) = 5 μM in PS120 fibroblasts] and NHE3 ( K i = 650 μM). Results showed that NHE2 and NHE3 contribute to basal BBMV uptake at all ages. Uptake levels were highest in 6-wk-old rats, lower in adult rats, and lowest in 2-wk-old (suckling) and 3-wk-old (weanling) rats. NHE3 contribution ranged from 92% at 6 wk of age to 59% at 2 and 3 wk of age. NHE3 inhibition by 800 μM HOE-694 was 38–45%. Statistical analysis showed that HOE-694 had a significant effect at both concentrations at all ages and that differences were present between all ages except 2- and 3-wk rats (at all HOE-694 concentrations). Northern blot analyses of jejunal mucosa showed lowest NHE3 mRNA levels in 2-wk animals and higher levels in all other age groups. Polyclonal antibodies were developed against an NHE3 COOH-terminal fusion protein, and antiserum was characterized with NHE3-transfected PS120 cells and by immunohistochemistry. Western blot analyses showed lowest protein levels in 2-wk animals and higher levels in the other ages. Suckling rats were subcutaneously injected with methylprednisone (MP) for 2 days and killed 1 day later. Northern blot analyses showed a twofold increase in NHE3 mRNA expression with MP treatment. Immunoblot analyses showed a 2.5-fold increase in NHE3 immunoreactive protein levels with MP injection. Overall, these data suggest that NHE3 is regulated during ontogeny and that ontogenic changes are most apparent around the time of weaning. Furthermore, the data suggest that NHE3 is regulated at transcriptional and posttranscriptional levels during mammalian intestinal development.

Dissimilar Anxiety-like Behavior in Prepubertal and Young Adult Female Rats on Acute Exposure to Aluminium

2021 ◽  
Vol 22 ◽  
Author(s):  
Trina Sengupta ◽  
Sutirtha Ghosh ◽  
Archana Gaur T. ◽  
Prasunpriya Nayak
Keyword(s):  
Body Weight ◽  
Young Adult ◽  
Adult Female ◽  
Developmental Stages ◽  
Elevated Plus Maze ◽  
Age Groups ◽  
Female Rats ◽  
Acute Exposure ◽  
Adult Rats ◽  
Plus Maze

Background: Puberty is a developmental transition in which an estrogenic surge occurs, mediating the release of xenoestrogens, like aluminium. Aluminium’s effect on anxiety in rodents at the different developmental stages is inconsistent. Aims: This study aimed at investigating the effect of the metalloestrogenic property of aluminium on anxiety-like behavioral changes in prepubertal and young adult female rats. Objective: Considering this aim, our objective was to evaluate the anxiety-like behavior by the elevated plus maze in prepubertal and young adult female rats with or without acute exposure to aluminium. Methods: To address this property of aluminium, 5mg/Kg body weight (Al-5) and 10 mg/Kg body weight (Al-10) of aluminium was administered intraperitoneally to female rats at two developmental stages, prepubertal (PP; n = 8 for each dose) and young adult (YA; n = 6 for each dose) for two weeks. Post-treatment, three days behavioral assessment of the rats was done employing elevated plus maze. Results: Reduced escape latency was seen in Al-5, Al-10 pre-pubertal rats, and Al-5 young-adult rats on day 3. A significant reduction in open arm time was seen in the Al-5 young-adult rats. Aluminium treatment in the pre-pubertal rats reduced their head dipping and grooming. Reduced sniffing, head dipping, and stretch-attended posture in the treated young-adult female rats showed that they had impaired risk-taking tendency. Conclusion: Differential effect on the anxiety-like behavior in the pre-pubertal and young-adult female rats might be due to the metalloestrogenic property of aluminium, acting differently on the two age groups.

Growth pattern of temporal bone pneumatization: a computed tomography study with consecutive age groups

2018 ◽  
Vol 41 (2) ◽  
pp. 221-225 ◽  
Author(s):  
Pengfei Zhao ◽  
Heyu Ding ◽  
Han Lv ◽  
Jing Li ◽  
Xuehuan Liu ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Temporal Bone ◽  
Growth Pattern ◽  
Age Groups ◽  
Temporal Bone Pneumatization

scholarly journals Aging and acute exercise enhance free radical generation in rat skeletal muscle

1999 ◽  
Vol 87 (1) ◽  
pp. 465-470 ◽  
Author(s):  
J. Bejma ◽  
L. L. Ji
Keyword(s):  
Skeletal Muscle ◽  
Lipid Peroxidation ◽  
Acute Exercise ◽  
Muscle Protein ◽  
Vastus Lateralis ◽  
Age Groups ◽  
Protein Carbonyl ◽  
Biological Aging ◽  
Young Rats ◽  
Old Rats

Reactive oxygen species (ROS) are implicated in the mechanism of biological aging and exercise-induced oxidative damage. The present study examined the effect of an acute bout of exercise on intracellular ROS production, lipid and protein peroxidation, and GSH status in the skeletal muscle of young adult (8 mo, n = 24) and old (24 mo, n = 24) female Fischer 344 rats. Young rats ran on a treadmill at 25 m/min and 5% grade until exhaustion (55.4 ± 2.7 min), whereas old rats ran at 15 m/min and 5% grade until exhaustion (58.0 ± 2.7 min). Rate of dichlorofluorescin (DCFH) oxidation, an indication of ROS and other intracellular oxidants production in the homogenate of deep vastus lateralis, was 77% ( P < 0.01) higher in rested old vs. young rats. Exercise increased DCFH oxidation by 38% ( P < 0.09) and 50% ( P < 0.01) in the young and old rats, respectively. DCFH oxidation in isolated deep vastus lateralis mitochondria with site 1 substrates was elevated by 57% ( P < 0.01) in old vs. young rats but was unaltered with exercise. Significantly higher DCFH oxidation rate was also found in aged-muscle mitochondria ( P < 0.01), but not in homogenates, when ADP, NADPH, and Fe3+ were included in the assay medium without substrates. Lipid peroxidation in muscle measured by malondialdehyde content showed no age effect, but was increased by 20% ( P < 0.05) with exercise in both young and old rats. Muscle protein carbonyl formation was unaffected by either age or exercise. Mitochondrial GSH/ GSSG ratio was significantly higher in aged vs. young rats ( P < 0.05), whereas exercise increased GSSG content and decreased GSH/GSSG in both age groups ( P < 0.05). These data provided direct evidence that oxidant production in skeletal muscle is increased in old age and during prolonged exercise, with both mitochondrial respiratory chain and NADPH oxidase as potential sources. The alterations of muscle lipid peroxidation and mitochondrial GSH status were consistent with these conclusions.

Gastrointestinal iron and cobalt absorption and iron status in young rats and guinea pigs

1995 ◽  
Vol 14 (12) ◽  
pp. 949-954 ◽  
Author(s):  
Gpl Naylor ◽  
JD Harrison
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
Iron Status ◽  
Age Groups ◽  
Gastrointestinal Absorption ◽  
Whole Body ◽  
Suckling Period ◽  
Young Rats ◽  
Body Retention ◽  
Different Ages

The gastrointestinal absorption of Fe and Co by rats and guinea pigs of different ages was measured by comparing the whole-body retention of 59Fe and 57Co after oral and intraperitoneal administrations. The age-groups studied included newborn, weanlings and adults. The absorption of both Fe and Co decreased markedly with age in both rats and guinea pigs. In the rat, absorption remained ele vated during the suckling period, while in the guinea pig absorption decreased markedly during suckling. In both species, Fe and Co absorption were similar, and remained elevated above adult values for some time after weaning. The generally greater absorption of Fe and Co by rats than by guinea pigs and the longer duration of maximal absorp tion in the rats may have involved differences in Fe status in the two species and differences in the timing of gut mat uration.

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