Cardiac output in adult and neonatal rats utilizing impedance cardiography

1987 ◽  
Vol 253 (5) ◽  
pp. H1298-H1304
Author(s):  
R. W. Gotshall ◽  
J. C. Breay-Pilcher ◽  
B. D. Boelcskevy
Keyword(s):  
Cardiac Output ◽  
Impedance Cardiography ◽  
Small Animals ◽  
Neonatal Rats ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Sprague Dawley Rats ◽  
Head Up Tilt ◽  
Old Rats ◽  
Preload Reduction

Impedance cardiography (IC) has the potential to be applied to very small animals for the measurement of cardiac output (Q). To evaluate this, Q measured by impedance (ZQ) and thermal dilution (TDQ) were compared in adult Sprague-Dawley rats. Absolute values for TDQ were comparable with ZQ (e.g., 29.7 vs. 26.0 ml.min-1.100 g-1), and both equally followed the change in Q caused by hemorrhage and reinfusion of blood. IC was also evaluated in neonatal rats (1 and 7 day old). Control ZQ values were 113 ml.min-1.100 g-1 for the 1-day-old rats, and 104 ml.min-1.100 g-1 for 7-day-old rats. Both stroke volume and Q decreased with head-up tilt and increased with head-down tilt for both ages. Therefore, in the neonate, ZQ decreased appropriately with age and with preload reduction. From these results, it is concluded that IC can be utilized to evaluate cardiac function in neonatal and adult rats.

Kinetic impairment of nitrogen and muscle glutamine metabolisms in old glucocorticoid-treated rats

1999 ◽  
Vol 276 (3) ◽  
pp. E558-E564 ◽  
Author(s):  
Regine Minet-Quinard ◽  
Christophe Moinard ◽  
Françoise Villie ◽  
Stephane Walrand ◽  
Marie-Paule Vasson ◽  
...  
Keyword(s):  
Control Group ◽  
Synthetase Activity ◽  
Aged Rats ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Glucocorticoid Treatment ◽  
Sprague Dawley Rats ◽  
End Of Treatment ◽  
Catabolic State ◽  
Old Rats

Aged rats are more sensitive to injury, possibly through an impairment of nitrogen and glutamine (Gln) metabolisms mediated by glucocorticoids. We studied the metabolic kinetic response of adult and old rats during glucocorticoid treatment. The male Sprague-Dawley rats were 24 or 3 mo old. Both adult and old rats were divided into 7 groups. Groups labeled G3, G5, and G7 received, by intraperitoneal injection, 1.50 mg/kg of dexamethasone (Dex) for 3, 5, and 7 days, respectively. Groups labeled G3PF, G5PF, and G7PF were pair fed to the G3, G5, or G7 groups and were injected with an isovolumic solution of NaCl. One control group comprised healthy rats fed ad libitum. The response to aggression induced specifically by Dex (i.e., allowing for variations in pair-fed controls) appeared later in the aged rats (decrease in nitrogen balance from day 1 in adults but only from day 4 in old rats). The adult rats rapidly adapted to Dex treatment, whereas the catabolic state worsened until the end of treatment in the old rats. Gln homeostasis was not maintained in the aged rats; despite an early increase in muscular Gln synthetase activity, the Gln pool was depleted. These results suggest a kinetic impairment of both nitrogen and muscle Gln metabolisms in response to Dex with aging.

scholarly journals Ventilatory responses to ozone are reduced in immature rats

2000 ◽  
Vol 88 (6) ◽  
pp. 2023-2030 ◽  
Author(s):  
S. A. Shore ◽  
J. H. Abraham ◽  
I. N. Schwartzman ◽  
G. G. Krishna Murthy ◽  
J. D. Laporte
Keyword(s):  
Bronchoalveolar Lavage ◽  
Ventilatory Response ◽  
Minute Ventilation ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Ventilatory Responses ◽  
Sprague Dawley Rats ◽  
Immature Rats ◽  
Old Rats ◽  
Induced Changes

During ozone (O3) exposure, adult rats decrease their minute ventilation (V˙e). To determine whether such changes are also observed in immature animals, Sprague-Dawley rats, aged 2, 4, 6, 8, or 12 wk, were exposed to O3(2 ppm) in nose-only-exposure plethysmographs. BaselineV˙e normalized for body weight decreased with age from 2.1 ± 0.1 ml ⋅ min−1⋅ g−1in 2-wk-old rats to 0.72 ± 0.03 ml ⋅ min−1⋅ g−1in 12-wk-old rats, consistent with the higher metabolic rates of younger animals. In adult (8- and 12-wk-old) rats, O3caused 40–50% decreases in V˙e that occurred primarily as the result of a decrease in tidal volume. In 6-wk-old rats, O3-induced changes inV˙e were significantly less, and in 2- and 4-wk-old rats, no significant changes inV˙e were observed during O3exposure. The increased baseline V˙e and the smaller decrements in V˙e induced by O3in the immature rats imply that their delivered dose of O3is much higher than in adult rats. To determine whether these differences in O3dose influence the extent of injury, we measured bronchoalveolar lavage protein concentrations. The magnitude of the changes in bronchoalveolar lavage induced by O3was significantly greater in 2- than in 8-wk-old rats (267 ± 47 vs. 165 ± 22%, respectively, P < 0.05). O3exposure also caused a significant increase in PGE2in 2-wk-old but not in adult rats. The results indicate that the ventilatory response to O3is absent in 2-wk-old rats and that lack of this response, in conjunction with a greater specific ventilation, leads to greater lung injury.

scholarly journals The development of arylsulphatase in the small intestine of the rat

1969 ◽  
Vol 114 (2) ◽  
pp. 343-350 ◽  
Author(s):  
S. H. Danovitch ◽  
L. Laster
Keyword(s):  
Small Intestine ◽  
Specific Activity ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Ph Optimum ◽  
Distal Small Intestine ◽  
Sprague Dawley Rats ◽  
Proximal Small Intestine ◽  
Liver And Kidney ◽  
Old Rats

1. Arylsulphatase activity was measured in stomach, proximal and distal third of small intestine, colon, liver and kidney of foetal and neonatal Sprague–Dawley rats and Swiss mice, with nitrocatechol sulphate as substrate. 2. The specific activity in the distal small intestine, but not in the stomach, proximal small intestine or colon, increased about fourfold between 5 and 16 days after birth in both conventional and germ-free rats. 3. No comparable increase occurred in the distal small intestine of the mouse. 4. The specific activity of acid phosphatase in the distal small intestine of the rat rose only slightly when the arylsulphatase activity increased. 5. The pH optimum and Michaelis constant of arylsulphatase activity of the distal small intestine were similar for 1-day-old, 9-day-old and adult rats. 6. When extracts of distal small intestine of 1-day-old and 9-day-old rats were incubated together, the arylsulphatase activities were additive.

Localization of cGMP after infusion of ANP or nitroprusside in the maturing rat

1992 ◽  
Vol 262 (3) ◽  
pp. F417-F424 ◽  
Author(s):  
R. L. Chevalier ◽  
R. J. Fern ◽  
M. Garmey ◽  
S. S. el-Dahr ◽  
R. A. Gomez ◽  
...  
Keyword(s):  
Guanylate Cyclase ◽  
Soluble Guanylate Cyclase ◽  
Mesangial Cells ◽  
Immunoperoxidase Technique ◽  
Neonatal Rats ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Sprague Dawley Rats ◽  
Specific Localization

To determine the ontogeny of intrarenal distribution of guanosine 3',5'-cyclic monophosphate (cGMP) formation in response to atrial natriuretic peptide (ANP) or sodium nitroprusside (SNP), adult and neonatal Sprague-Dawley rats were anesthetized and infused for 60 s with rat ANP (5-2,500 micrograms/kg) or SNP (0.1-10.0 mg/kg). cGMP was identified by the immunoperoxidase technique using a specific antibody. In adult rats, infusion of ANP localized cGMP primarily to the glomerular podocytes, whereas stimulation by SNP increased cGMP in the mesangium only (P less than 0.01). In neonatal rats, although overall renal cGMP immunostaining was greater than in adults, specific localization to podocytes (ANP) or mesangium (SNP) resulted only with higher doses of agonists. Although basal generation of cGMP by isolated glomeruli was greater in neonatal rats, the threshold for stimulation by ANP was lower in glomeruli from adult rats. We conclude that in vivo ANP stimulates glomerular particulate guanylate cyclase primarily in the podocytes, whereas SNP stimulates soluble guanylate cyclase localized to the mesangial cells. There is a maturational increase in the sensitivity for activation of glomerular particulate and soluble guanylate cyclase.

Light and electron microscopic investigation of adenohypophyses of germfree, food-restricted, and germfree-food restricted aging, male lobund-wistar rats

1988 ◽  
Vol 46 ◽  
pp. 352-353
Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Aging Male ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Sprague Dawley Rats ◽  
Old Rats ◽  
Ad Libitum ◽  
Microscopic Findings

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.

scholarly journals Intermittent hypoxia inhibits mandibular cartilage growth with reduced TGF-β and SOX9 expressions in neonatal rats

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Kochakorn Lekvijittada ◽  
Jun Hosomichi ◽  
Hideyuki Maeda ◽  
Haixin Hong ◽  
Chidsanu Changsiripun ◽  
...  
Keyword(s):  
Bone Mineral ◽  
Intermittent Hypoxia ◽  
Hyaline Cartilage ◽  
Body Weight Gain ◽  
Mandibular Condyle ◽  
Neonatal Rats ◽  
Sprague Dawley ◽  
Cartilage Growth ◽  
Condylar Cartilage ◽  
Sprague Dawley Rats

AbstractIntermittent hypoxia (IH) has been associated with skeletal growth. However, the influence of IH on cartilage growth and metabolism is unknown. We compared the effects of IH on chondrocyte proliferation and maturation in the mandibular condyle fibrocartilage and tibial hyaline cartilage of 1-week-old male Sprague–Dawley rats. The rats were exposed to normoxic air (n = 9) or IH at 20 cycles/h (nadir, 4% O2; peak, 21% O2; 0% CO2) (n = 9) for 8 h each day. IH impeded body weight gain, but not tibial elongation. IH also increased cancellous bone mineral and volumetric bone mineral densities in the mandibular condylar head. The mandibular condylar became thinner, but the tibial cartilage did not. IH reduced maturative and increased hypertrophic chondrocytic layers of the middle and posterior mandibular cartilage. PCR showed that IH shifted proliferation and maturation in mandibular condyle fibrocartilage toward hypertrophic differentiation and ossification by downregulating TGF-β and SOX9, and upregulating collagen X. These effects were absent in the tibial growth plate hyaline cartilage. Our results showed that neonatal rats exposed to IH displayed underdeveloped mandibular ramus/condyles, while suppression of chondrogenesis marker expression was detected in the growth-restricted condylar cartilage.

scholarly journals Effects of adolescent caffeine consumption on cocaine self-administration and reinstatement of cocaine seeking

2018 ◽  
Vol 33 (1) ◽  
pp. 132-144
Author(s):  
Tracey A Larson ◽  
Casey E O’Neill ◽  
Michaela P Palumbo ◽  
Ryan K Bachtell
Keyword(s):  
Dose Response ◽  
Extinction Training ◽  
Schedules Of Reinforcement ◽  
Sprague Dawley ◽  
Self Administration ◽  
Caffeine Consumption ◽  
Adult Rats ◽  
Sprague Dawley Rats ◽  
Cocaine Seeking ◽  
Administration Procedure

Background: Caffeine consumption by children and adolescents has risen dramatically in recent years, yet the lasting effects of caffeine consumption during adolescence remain poorly understood. Aim: These experiments explore the effects of adolescent caffeine consumption on cocaine self-administration and seeking using a rodent model. Methods: Sprague-Dawley rats consumed caffeine for 28 days during the adolescent period. Following the caffeine consumption period, the caffeine solution was replaced with water for the remainder of the experiment. Age-matched control rats received water for the duration of the study. Behavioral testing in a cocaine self-administration procedure occurred during adulthood (postnatal days 62–82) to evaluate how adolescent caffeine exposure influenced the reinforcing properties of cocaine. Cocaine seeking was also tested during extinction training and reinstatement tests following cocaine self-administration. Results: Adolescent caffeine consumption increased the acquisition of cocaine self-administration and increased performance on different schedules of reinforcement. Consumption of caffeine in adult rats did not produce similar enhancements in cocaine self-administration. Adolescent caffeine consumption also produced an upward shift in the U-shaped dose response curve on cocaine self-administration maintained on a within-session dose-response procedure. Adolescent caffeine consumption had no effect on cocaine seeking during extinction training or reinstatement of cocaine seeking by cues or cocaine. Conclusions: These findings suggest that caffeine consumption during adolescence may enhance the reinforcing properties of cocaine, leading to enhanced acquisition that may contribute to increased addiction vulnerability.

scholarly journals Protective effects of dietary fibre against manganese-induced neurobehavioral aberrations in rats

2012 ◽  
Vol 63 (3) ◽  
pp. 263-270 ◽  
Author(s):  
Xiu-Quan Shi ◽  
Wei Yan ◽  
Ke-Yue Wang ◽  
Qi-Yuan Fan ◽  
Yan Zou
Keyword(s):  
Cerebral Cortex ◽  
Animal Feed ◽  
Oral Exposure ◽  
Protective Effects ◽  
Sprague Dawley ◽  
Adult Rats ◽  
Neurobehavioral Performance ◽  
Sprague Dawley Rats ◽  
Applied Dose ◽  
Mn Concentrations

We tested the hypothesis that dietary fi bre (DF) has protective effects against manganese (Mn)-induced neurotoxicity. Forty-eight one-month old Sprague-Dawley rats were randomly divided into six groups: control, 16 % DF, Mn (50 mg kg-1 body weight), Mn+ 4 % DF, Mn+ 8 % DF, and Mn+ 16 % DF. After oral administration of Mn (as MnCl2) by intragastric tube during one month, we determined Mn concentrations in the blood, liver, cerebral cortex, and stool and tested neurobehavioral functions. Administration of Mn was associated with increased Mn concentration in the blood, liver, and cerebral cortex and increased Mn excretion in the stool. Aberrations in neurobehavioral performance included increases in escape latency and number of errors and decrease in step-down latency. Irrespective of the applied dose, the addition of DF in forage decreased tissue Mn concentrations and increased Mn excretion rate in the stool by 20 % to 35 %. All neurobehavioral aberrations were also improved. Our fi ndings show that oral exposure to Mn may cause neurobehavioral abnormalities in adult rats that could be effi ciently alleviated by concomitant supplementation of DF in animal feed.

scholarly journals Synergistic toxicity in an in vivo model of neurodegeneration through the co-expression of human TDP-43M337V and tauT175D protein

2019 ◽  
Vol 7 (1) ◽  
Author(s):  
Alexander J. Moszczynski ◽  
Madeline Harvey ◽  
Niveen Fulcher ◽  
Cleusa de Oliveira ◽  
Patrick McCunn ◽  
...  
Keyword(s):  
Tau Protein ◽  
Sensorimotor Gating ◽  
In Vivo Model ◽  
Motor Deficits ◽  
Sprague Dawley ◽  
Tau Pathology ◽  
Adult Rats ◽  
Sprague Dawley Rats ◽  
Somatic Gene Transfer

Abstract Although it has been suggested that the co-expression of multiple pathological proteins associated with neurodegeneration may act synergistically to induce more widespread neuropathology, experimental evidence of this is sparse. We have previously shown that the expression of Thr175Asp-tau (tauT175D) using somatic gene transfer with a stereotaxically-injected recombinant adeno-associated virus (rAAV9) vector induces tau pathology in rat hippocampus. In this study, we have examined whether the co-expression of human tauT175D with mutant human TDP-43 (TDP-43M337V) will act synergistically. Transgenic female Sprague-Dawley rats that inducibly express mutant human TDP-43M337V using the choline acetyltransferase (ChAT) tetracycline response element (TRE) driver with activity modulating tetracycline-controlled transactivator (tTA) were utilized in these studies. Adult rats were injected with GFP-tagged tau protein constructs in a rAAV9 vector through bilateral stereotaxic injection into the hippocampus. Injected tau constructs were: wild-type GFP-tagged 2N4R human tau (tauWT; n = 8), GFP-tagged tauT175D 2N4R human tau (tauT175D, pseudophosphorylated, toxic variant, n = 8), and GFP (control, n = 8). Six months post-injection, mutant TDP-43M337V expression was induced for 30 days. Behaviour testing identified motor deficits within 3 weeks after TDP-43 expression irrespective of tau expression, though social behaviour and sensorimotor gating remained unchanged. Increased tau pathology was observed in the hippocampus of both tauWT and tauT175D expressing rats and tauT175D pathology was increased in the presence of cholinergic neuronal expression of human TDP-43M337V. These data indicate that co-expression of pathological TDP-43 and tau protein exacerbate the pathology associated with either individual protein.

scholarly journals Cerebral cortex does not modulate “regulated” decrease in core temperature during hypoxemia in rats

1998 ◽  
Vol 274 (4) ◽  
pp. R1158-R1161
Author(s):  
Evvi-Lynn M. Rollins ◽  
James E. Fewell
Keyword(s):  
Cerebral Cortex ◽  
Core Temperature ◽  
Cortical Spreading Depression ◽  
Spreading Depression ◽  
Temperature Response ◽  
Sprague Dawley ◽  
Adult Rats ◽  
The Core ◽  
Sprague Dawley Rats ◽  
Before And After

In newborns and adults of a number of species including humans, exposure to acute hypoxemia produces a “regulated” decease in core temperature, the mechanism of which is unknown. Considering that various cortical areas participate in autonomic regulation including thermoregulation, the present experiments were carried out to test the hypothesis that the cerebral cortex plays a role in modulating the regulated decrease in core temperature during acute hypoxemia. This hypothesis was tested by determining the core temperature response to acute hypoxemia in chronically instrumented adult Sprague-Dawley rats before and after cortical spreading depression (i.e., functional decortication) was produced by the local application of potassium chloride to the dura overlying the cerebral hemispheres. There was no effect of cortical spreading depression on baseline core temperature. Core temperature decreased during acute hypoxemia in a similar fashion when the cerebral cortex was intact as well as during functional decortication. Thus our data do not support the hypothesis that the cerebral cortex modulates the regulated decrease in core temperature that occurs in adult rats during acute hypoxemia.

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