Age-related declines in thirst and salt appetite responses in male Fischer 344×Brown Norway rats

Epidemiological evidence suggests that advancing age affects the cardiovascular system of men and women differently. The purpose of this study was to determine whether the effects of aging on nitric oxide synthase (NOS), oxidative stress, and vascular function are different in males and females. Mesenteric arteries from young (3 mo) and old (24 mo) male and female Fischer 344/Brown Norway rats were studied. Western blot analysis and NOS activity were performed on the homogenized mesenteric arterial bed separated into cytosolic and membrane-associated fractions. Plasma 8-isoprostane measurements assessed oxidative stress. Vascular reactivity was determined by using a wire myograph in the absence and presence of a NOS inhibitor, Nω-nitro-l-arginine, to examine endothelial function and basal and stimulated nitric oxide release. In additional arteries, reactivity was performed in the presence of polyethylene glycol-SOD to assess the impact of superoxide on vascular function. Among females, aging was associated with a decline in membrane-associated NOS activity and membrane-associated NOS III protein expression. Advancing age in males was associated with increased cytosolic NOS III protein expression. Among both males and females, advancing age resulted in increased oxidative stress. Vascular function was maintained with age in arteries from both males and females, and there was no difference in either basal or stimulated nitric oxide release with age. Despite sex-specific effects of advancing age on the NOS system and increases in markers of oxidative stress, vascular function is maintained in mesenteric arteries from aged Fischer 344/Brown Norway rats. These data suggest that age-related alterations in the resistance vasculature are complex and likely involve multiple compensating vasoactive pathways.

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Delayed non-matching to position performance in aged hybrid Fischer 344 × Brown Norway rats: a longitudinal study

Brain Research Bulletin ◽

10.1016/j.brainresbull.2004.04.017 ◽

2004 ◽

Vol 64 (1) ◽

pp. 39-46 ◽

Cited By ~ 6

Author(s):

Arjan Blokland ◽

Ayhan Şık ◽

F.Josef van der Staay

Keyword(s):

Longitudinal Study ◽

Brown Norway ◽

Fischer 344 ◽

Norway Rats ◽

Matching To Position

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Age-related synaptic changes in sensorimotor cortex of the Brown Norway X Fischer 344 rat

Brain Research ◽

10.1016/s0006-8993(00)02515-4 ◽

2000 ◽

Vol 872 (1-2) ◽

pp. 125-133 ◽

Cited By ~ 25

Author(s):

J.K Brunso-Bechtold ◽

M.C Linville ◽

W.E Sonntag

Keyword(s):

Sensorimotor Cortex ◽

Brown Norway ◽

Fischer 344 ◽

Age Related ◽

Fischer 344 Rat ◽

Synaptic Changes

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Lifelong caloric restriction prevents age-induced oxidative stress in the sympathoadrenal system of Fischer 344 x Brown Norway rats

Biochemical and Biophysical Research Communications ◽

10.1016/j.bbrc.2011.04.051 ◽

2011 ◽

Vol 408 (3) ◽

pp. 454-458 ◽

Cited By ~ 9

Author(s):

Melissa A. Whidden ◽

Nataliya Kirichenko ◽

Zekai Halici ◽

Benedek Erdos ◽

Thomas C. Foster ◽

...

Keyword(s):

Oxidative Stress ◽

Caloric Restriction ◽

Brown Norway ◽

Sympathoadrenal System ◽

Fischer 344 ◽

Norway Rats

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Hypotension- and osmotically induced thirst in old Brown Norway rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00118.2009 ◽

2009 ◽

Vol 297 (1) ◽

pp. R149-R157 ◽

Cited By ~ 11

Author(s):

Robert L. Thunhorst ◽

Terry G. Beltz ◽

Alan Kim Johnson

Keyword(s):

Arterial Pressure ◽

Brown Norway ◽

Aged Rats ◽

Middle Aged ◽

Young Rats ◽

Age Related ◽

Cellular Dehydration ◽

Old Rats ◽

Middle Aged Adult ◽

Norway Rats

Compared to young cohorts, old rats drink less water in response to several thirst-inducing stimuli. In these experiments, we characterized water drinking in response to hypotension and cellular dehydration in young (4 mo), middle-aged adult (12 mo) and old (29–30 mo) male Brown Norway rats. We injected the vasodilator, minoxidil as an intravenous bolus in a range of doses (0–20 mg/kg), so that drinking responses could be compared at equivalent reductions of arterial pressure. Old rats had greatly diminished reflex tachycardia and became significantly more hypotensive after minoxidil compared with young and middle-aged rats. When compared at equivalent reductions of arterial pressure, old rats drank one-third as much as middle-aged rats, and one-fifth as much as young rats. In addition, there were age-related deficits in drinking in response to a range of administered loads of sodium (0.15–2 M NaCl, 2 ml/100 g body wt). Urinary excretion of water and sodium in response to the loads was equivalent across ages. Both middle-aged and old rats were less able than young rats to repair their water deficits after sodium loading, attributable almost entirely to their reduced drinking responses compared with young rats. Lastly, age-related declines in drinking appeared to be more severe in response to hypotension than in response to cellular dehydration.

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Effects of long-term exposures to low iron and branched-chain amino acid containing diets on aging skeletal muscle of Fisher 344 × Brown Norway rats

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2017-0272 ◽

2018 ◽

Vol 43 (2) ◽

pp. 165-173 ◽

Cited By ~ 1

Author(s):

Yuho Kim ◽

Sok Sambo Men ◽

Chen Liang ◽

Candace N. Receno ◽

Tom D. Brutsaert ◽

...

Keyword(s):

Skeletal Muscle ◽

Muscle Mass ◽

Citrate Synthase ◽

Muscle Protein ◽

Iron Status ◽

Protein Carbonyls ◽

Brown Norway ◽

Age Related ◽

Branched Chain ◽

Norway Rats

Aging skeletal muscle displays an altered iron status that may promote oxidative stress and sarcopenia. A diet containing low iron (LI) could reduce muscle iron status and attenuate age-related muscle atrophy. Supplemental branched-chain amino acids (BCAA) may also alleviate sarcopenia by promoting muscle protein synthesis and iron status improvement. This study examined individual and combined effects of LI and BCAA diets on anabolic signaling and iron status in skeletal muscle of aging rats. Twenty-nine-month-old male Fisher 344 × Brown Norway rats consumed the following control-base diets: control + regular iron (35 mg iron/kg) (CR; n = 11); control + LI (∼6 mg iron/kg) (CL; n = 11); 2×BCAA + regular iron (BR; n = 10); and 2×BCAA + LI (BL; n = 12) for 12 weeks. Although LI and/or 2×BCAA did not affect plantaris muscle mass, 2×BCAA groups showed lower muscle iron content than did CR and CL groups (P < 0.05). p70 ribosomal protein S6 kinase phosphorylation was greater in 2×BCAA and LI animals compared with CR animals (P < 0.05). Interactions between IRON and BCAA were observed for proteins indicative of mitochondrial biogenesis (peroxisome proliferator-activated receptor gamma coactivator 1 alpha) and oxidative capacity (cytochrome c oxidase subunit 2 and citrate synthase) (P < 0.05) wherein the combined diet (BL) negated potential benefits of individual diets. Antioxidant capacity, superoxide dismutase activity, and oxidative injury (3-nitrotyrosine, protein carbonyls, and 4-hydroxynonenal) were similar between groups. In conclusion, 12 weeks of LI and 2×BCAA diets showed significant impacts on increasing anabolic signaling as well as ameliorating iron status; however, these interventions did not affect muscle mass.

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