Site- and compartment-specific changes in bone with hindlimb unloading in mature adult rats

The present study examined whether a prenatal low-protein diet programs a decrease in glomerular filtration rate (GFR) and an increase in systolic blood pressure (BP). In addition, we examined whether altering the postnatal nutritional environment of nursing neonatal rats affected GFR and BP when rats were studied as adults. Pregnant rats were fed a normal (20%) protein diet or a low-protein diet (6%) during the last half of pregnancy until birth, when rats were fed a 20% protein diet. Mature adult rats from the prenatal low-protein group had systolic hypertension and a GFR of 0.38 ± 0.03 versus 0.57 ± 0.05 ml·min−1·100 g body wt−1 in the 20% group ( P < 0.01). In cross-fostering experiments, mothers continued on the same prenatal diet until weaning. Prenatal 6% protein rats cross-fostered to a 20% mother on day 1 of life had a GFR of 0.53 ± 0.05 ml·min−1·100 g body wt−1, which was not different than the 20% group cross-fostered to a different 20% mother (0.45 ± 0.04 ml·min−1·100 g body wt−1). BP in the 6% to 20% group was comparable with the 20% to 20% group. Offspring of rats fed either 20% or 6% protein diets during pregnancy and cross-fostered to a 6% mother had elevated BP but a comparable GFR normalized to body weight as the 20% to 20% control group. Thus, a prenatal low-protein diet causes hypertension and a reduction in GFR in mature adult offspring, which can be modified by postnatal rearing.

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Age-dependent neurobehavioral responses by young and mature adult rats to systemic kainic acid

Restorative Neurology and Neuroscience ◽

10.3233/rnn-1996-10206 ◽

1996 ◽

Vol 10 (2) ◽

pp. 103-108

Author(s):

Cesario V. Borlongan ◽

Kimberly B. Bjugstad ◽

Christine E. Stahl ◽

Shajmil D. Ross ◽

Gary W. Arendash ◽

...

Keyword(s):

Kainic Acid ◽

Adult Rats ◽

Mature Adult ◽

Age Dependent

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ERK Is Involved in the Reorganization of Somatosensory Cortical Maps in Adult Rats Submitted to Hindlimb Unloading

PLoS ONE ◽

10.1371/journal.pone.0017564 ◽

2011 ◽

Vol 6 (3) ◽

pp. e17564 ◽

Cited By ~ 7

Author(s):

Erwan Dupont ◽

Laurence Stevens ◽

Laetitia Cochon ◽

Maurice Falempin ◽

Bruno Bastide ◽

...

Keyword(s):

Hindlimb Unloading ◽

Adult Rats ◽

Cortical Maps

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Age exacerbates chronic catecholamine-induced impairments in contractile reserve in the rat

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00756.2010 ◽

2011 ◽

Vol 301 (2) ◽

pp. R491-R499 ◽

Cited By ~ 3

Author(s):

John T. Liles ◽

Kevin K. Ida ◽

Kristin M. Joly ◽

Joseph Chapo ◽

Craig F. Plato

Keyword(s):

Cardiac Hypertrophy ◽

Caspase 3 ◽

Left Ventricular ◽

Calcium Handling ◽

Contractile Reserve ◽

Adult Rats ◽

Mature Adult ◽

Age Related ◽

Catecholamine Excess ◽

Systolic Performance

Contractile reserve decreases with advancing age and chronic isoproterenol (ISO) administration is a well-characterized model of cardiac hypertrophy known to impair cardiovascular function. This study evaluated whether nonsenescent, mature adult rats are more susceptible to detrimental effects of chronic ISO administration than younger adult rats. Rats received daily injections of ISO (0.1 mg/kg sc) or vehicle for 3 wk. ISO induced a greater impairment in contractile reserve [maximum of left ventricular pressure development (Δ+dP/d tmax)] in mature adult ISO-treated (MA-ISO) than in young adult ISO-treated rats (YA-ISO) in response to infusions of mechanistically distinct inotropes (digoxin, milrinone; 20–200 μl·kg−1·min−1), while basal and agonist-induced changes in heart rate and systolic arterial pressure (SAP) were not different across groups. ISO decreased expression of the calcium handling protein, sarco(endo)plasmic reticulum Ca2+-ATPase-2a, in MA-ISO compared with YA, YA-ISO, and MA rats. Chronic ISO also induced greater increases in cardiac hypertrophy [left ventricular (LV) index: 33 ± 3 vs. 22 ± 5%] and caspase-3 activity (34 vs. 5%) in MA-ISO relative to YA-ISO rats. Moreover, β-myosin heavy chain (β-MHC) and atrial natriuretic factor (ANF) mRNA expression was significantly elevated in MA-ISO. These results demonstrate that adult rats develop greater impairments in systolic performance than younger rats when exposed to chronic catecholamine excess. Reduced contractile reserve may result from calcium dysregulation, increased caspase-3 activity, or increased β-MHC and ANF expression. Although several studies report age-related declines in systolic performance in older and senescent animals, the present study demonstrates that catecholamine excess induces reductions in systolic performance significantly earlier in life.

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Effect of hindlimb unloading on motor activity in adult rats: Impact of prenatal stress.

Behavioral Neuroscience ◽

10.1037/0735-7044.121.1.177 ◽

2007 ◽

Vol 121 (1) ◽

pp. 177-185 ◽

Cited By ~ 9

Author(s):

M. H. Canu ◽

M. Darnaudéry ◽

M. Falempin ◽

S. Maccari ◽

O. Viltart

Keyword(s):

Motor Activity ◽

Prenatal Stress ◽

Hindlimb Unloading ◽

Adult Rats

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Ultrafine Particulate Matter Combined With Ozone Exacerbates Lung Injury in Mature Adult Rats With Cardiovascular Disease

Toxicological Sciences ◽

10.1093/toxsci/kfy018 ◽

2018 ◽

Vol 163 (1) ◽

pp. 140-151 ◽

Cited By ~ 5

Author(s):

Emily M Wong ◽

William F Walby ◽

Dennis W Wilson ◽

Fern Tablin ◽

Edward S Schelegle

Keyword(s):

Cardiovascular Disease ◽

Particulate Matter ◽

Lung Injury ◽

Adult Rats ◽

Mature Adult ◽

Ultrafine Particulate Matter

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HSP25 can modulate myofibrillar desmin cytoskeleton following the phosphorylation at Ser15 in rat soleus muscle

Journal of Applied Physiology ◽

10.1152/japplphysiol.00783.2011 ◽

2012 ◽

Vol 112 (1) ◽

pp. 176-186 ◽

Cited By ~ 12

Author(s):

Fuminori Kawano ◽

Ryo Fujita ◽

Naoya Nakai ◽

Masahiro Terada ◽

Takashi Ohira ◽

...

Keyword(s):

Soleus Muscle ◽

Muscle Fibers ◽

Hindlimb Unloading ◽

Proximity Ligation Assay ◽

Cytoplasmic Fraction ◽

Normal Muscle ◽

Histochemical Analysis ◽

Adult Rats ◽

Proximity Ligation ◽

Rat Soleus Muscle

The main purpose of the present study was to investigate the role(s) of 25-kDa heat shock protein (HSP25) in the regulation and integration of myofibrillar Z-disc structure during down- or upregulation of the size in rat soleus muscle fibers. Hindlimb unloading by tail suspension was performed in adult rats for 7 days, and reloading was allowed for 5 days after the termination of suspension. Interaction of HSP25 and Z-disc proteins, phosphorylation status, distribution, and complex formation of HSP25 were investigated. Non- and single-phosphorylated HSP25s were generally expressed in the cytoplasmic fraction of normal muscle. The level of total HSP25, as well as the phosphorylation ratio, did not change significantly in response to atrophy. Increased expressions of HSP25, phosphorylated at serine 15 (p-Ser15) and dual-phosphorylated form, were noted, when atrophied muscles were reloaded. Myofibrillar HSP25 was also noted in reloaded muscle. Histochemical analysis further indicated the localization of p-Ser15 in the regions with disorganization of Z-disc structure in reloaded muscle fibers. HSP25 formed a large molecular complex in the cytoplasmic fraction of normal muscle, whereas dissociation of free HSP25 with Ser15 phosphorylation was noted in reloaded muscle. The interaction of p-Ser15 with desmin and actinin was detected in Z-discs by proximity ligation assay. Strong interaction between p-Ser15 and desmin, but not actinin, was noted in the disorganized areas. These results indicated that HSP25 contributed to the desmin cytoskeletal organization following the phosphorylation at Ser15 during reloading and regrowing of soleus muscle.

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