Sympathetic pharmacological denervation in ageing rats: effects on ovulatory response and follicular population

2007 ◽  
Vol 19 (8) ◽  
pp. 954 ◽  
Author(s):  
Rebeca Chávez-Genaro ◽  
Paula Lombide ◽  
Roberto Domínguez ◽  
Patricia Rosas ◽  
Francisco Vázquez-Cuevas
Keyword(s):  
Young Adult ◽  
Combined Treatment ◽  
Ovarian Response ◽  
Sympathetic Denervation ◽  
Progressive Reduction ◽  
Adult Rats ◽  
Reproductive Senescence ◽  
Noradrenergic Innervation ◽  
Old Rats ◽  
Control Adult

The present study analyses the participation of ovarian innervation during reproductive senescence. We use the model of acute peripheral pharmacological sympathetic denervation with guanethidine in young (3 months old), middle-aged (12 months old) or old (18 months old) rats with spontaneous or induced ovulation. Ovarian levels of norepinephrine (NE) were measured by HPLC and the oestrous cycle, the number of ovulating animals and the percentage of atretic follicles were also assessed. Aged animals showed a progressive reduction in ovulatory capacity and an increase in ovarian NE content. Acute denervation increased the percentage of healthy follicles in 12- and 18-month-old rats compared with control adult animals. Combined treatment of denervation plus stimulation with gonadotrophins doubled the number of ova shed in young adult rats and restablished a partial ovulation in 12-month-old rats. The results suggest that ovarian noradrenergic innervation plays a modulator role in ovarian physiology during the ageing ovary process. The action of ovarian noradrenergic innervation seems to be associated with folliculogenesis and the ovarian response to gonadotrophins.

scholarly journals Differential effects of targeted tongue exercise and treadmill running on aging tongue muscle structure and contractile properties

2013 ◽  
Vol 114 (4) ◽  
pp. 472-481 ◽  
Author(s):  
Heidi Kletzien ◽  
John A. Russell ◽  
Glen E. Leverson ◽  
Nadine P. Connor
Keyword(s):  
Young Adult ◽  
Exercise Group ◽  
Contractile Properties ◽  
Treadmill Running ◽  
Brown Norway ◽  
Middle Aged ◽  
Adult Rats ◽  
Tongue Muscle ◽  
Muscle Structure ◽  
Old Rats

Age-associated changes in tongue muscle structure and strength may contribute to dysphagia in elderly people. Tongue exercise is a current treatment option. We hypothesized that targeted tongue exercise and nontargeted exercise that activates tongue muscles as a consequence of increased respiratory drive, such as treadmill running, are associated with different patterns of tongue muscle contraction and genioglossus (GG) muscle biochemistry. Thirty-one young adult, 34 middle-aged, and 37 old Fischer 344/Brown Norway rats received either targeted tongue exercise, treadmill running, or no exercise (5 days/wk for 8 wk). Protrusive tongue muscle contractile properties and myosin heavy chain (MHC) composition in the GG were examined at the end of 8 wk across groups. Significant age effects were found for maximal twitch and tetanic tension (greatest in young adult rats), MHCIIb (highest proportion in young adult rats), MHCIIx (highest proportion in middle-aged and old rats), and MHCI (highest proportion in old rats). The targeted tongue exercise group had the greatest maximal twitch tension and the highest proportion of MHCI. The treadmill running group had the shortest half-decay time, the lowest proportion of MHCIIa, and the highest proportion of MHCIIb. Fatigue was significantly less in the young adult treadmill running group and the old targeted tongue exercise group than in other groups. Thus, tongue muscle structure and contractile properties were affected by both targeted tongue exercise and treadmill running, but in different ways. Studies geared toward optimizing dose and manner of providing targeted and generalized tongue exercise may lead to alternative tongue exercise delivery strategies.

scholarly journals Para-chloroamphetamine (PCA)-induced ejaculation in aged rats, semen analysis and artificial insemination

1996 ◽  
Vol 30 (4) ◽  
pp. 332-336 ◽  
Author(s):  
Toru R. Saito ◽  
Ryoji Hokao ◽  
Yasumasa Wakafuji ◽  
Noriyuki Igarashi ◽  
Yoshio Agematsu ◽  
...  
Keyword(s):  
Young Adult ◽  
Sperm Motility ◽  
Artificial Insemination ◽  
Semen Analysis ◽  
Active Movement ◽  
Aged Rats ◽  
Adult Rats ◽  
Reproductive Ability ◽  
Sperm Counts ◽  
Old Rats

The present study was undertaken to determine sperm motility and counts in semen yielded by para-chloroamphetamine (PCA)-induced ejaculation of aged rats which had lost their reproductive ability, and to attempt artificial insemination with suspensions of spermatozoa obtained in this way. The semen yielded by PCA-induced ejaculation from aged (75-week-old) rats had average sperm counts of 0.82±0.69 × 107, which were much lower than the average counts (9.42±1.65 × 107) for semen spontaneously ejaculated by young adult rats (14 weeks old). However, 77.5% of the spermatozoa contained in the PCA-induced semen were rated as showing the most active movement. Spermatozoa collected in this way were injected into the upper parts of both uterine horns or into both ovarian bursae. Both methods made the females pregnant, but the results were better after injection into the ovarian bursae. The offspring born to these females showed no abnormalities.

scholarly journals Effect of IGF-I and PDGF administered in vivo on the expression of osteoblast-related genes in old rats

2002 ◽  
Vol 174 (1) ◽  
pp. 63-70 ◽  
Author(s):  
H Tanaka ◽  
A Wakisaka ◽  
H Ogasa ◽  
S Kawai ◽  
CT Liang
Keyword(s):  
Gene Expression ◽  
Growth Factors ◽  
Mrna Expression ◽  
Combined Treatment ◽  
Mrna Levels ◽  
Adult Rats ◽  
Igf I ◽  
Old Rats ◽  
Osteoblast Markers ◽  
Marrow Ablation

In order to establish the cellular basis for using growth factors as possible therapeutic agents for the age-dependent deficit in bone formation activity, we examined the individual and combined effects of IGF-I and/or platelet-derived growth factor (PDGF) on the gene expression of osteoblast-related markers in male rats. The expression of osteoblast markers was examined in the femurs of adult and old rats following marrow ablation, which amplifies gene expression activity. The mRNA levels of collagen(alpha1) (I) (COLI), alkaline phosphatase (AP), osteopontin (OP) and osteocalcin (OC) were significantly lower in the old as compared with the adult rats. To determine whether growth factors can abolish the age-related deficits in mRNA expression in old bone, PDGF and/or IGF-I were infused directly into the right femur for 5 days following marrow ablation. The contralateral femur was infused with vehicle only and used as a control. PDGF stimulated the expression of OP mRNA in both adult and old rats, whereas COLI, AP and OC mRNAs were not affected. IGF-I infusion did not have a significant effect on mRNA expression in adult rats. In contrast, treatment with IGF-I significantly enhanced the mRNA levels of COLI, AP and OP in old rats. To examine whether the combination of both factors could affect the expression of osteoblast markers synergistically, PDGF and IGF-I were infused together. In adult bones, the combined treatment with PDGF and IGF-I caused a slight increase in the level of OP gene expression but no change in AP, OC or COLI genes. Although neither IGF-I nor PDGF alone was effective in stimulating the expression of OC, the combined treatment in old bones enhanced OC expression significantly. The expression of COLI, AP and OP was also stimulated, but the stimulation was no different from that of IGF-I alone. In PDGF plus IGF-I treatment with a high dose, no dose-response effects were observed. Within the limits of the present study, it is suggested that IGF-I and, to a much lesser extent, PDGF may partially restore the deficit in the expression of osteoblast markers in old bones, and that the combination of both factors is slightly better than IGF-I alone in stimulating OC expression.

Myogenic regulatory factors during regeneration of skeletal muscle in young, adult, and old rats

1997 ◽  
Vol 83 (4) ◽  
pp. 1270-1275 ◽  
Author(s):  
Daniel R. Marsh ◽  
David S. Criswell ◽  
James A. Carson ◽  
Frank W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Young Adult ◽  
Muscle Regeneration ◽  
Tibialis Anterior Muscle ◽  
Brown Norway ◽  
Mrna Levels ◽  
Myogenic Regulatory Factors ◽  
Adult Rats ◽  
Regulatory Factors ◽  
Old Rats

Marsh, Daniel R., David S. Criswell, James A. Carson, and Frank W. Booth. Myogenic regulatory factors during regeneration of skeletal muscle in young, adult, and old rats. J. Appl. Physiol. 83(4): 1270–1275, 1997.—Myogenic factor mRNA expression was examined during muscle regeneration after bupivacaine injection in Fischer 344/Brown Norway F1 rats aged 3, 18, and 31 mo of age (young, adult, and old, respectively). Mass of the tibialis anterior muscle in the young rats had recovered to control values by 21 days postbupivacaine injection but in adult and old rats remained 40% less than that of contralateral controls at 21 and 28 days of recovery. During muscle regeneration, myogenin mRNA was significantly increased in muscles of young, adult, and old rats 5 days after bupivacaine injection. Subsequently, myogenin mRNA levels in young rat muscle decreased to postinjection control values by day 21 but did not return to control values in 28-day regenerating muscles of adult and old rats. The expression of MyoD mRNA was also increased in muscles at day 5 of regeneration in young, adult, and old rats, decreased to control levels by day 14 in young and adult rats, and remained elevated in the old rats for 28 days. In summary, either a diminished ability to downregulate myogenin and MyoD mRNAs in regenerating muscle occurs in old rat muscles, or the continuing myogenic effort includes elevated expression of these mRNAs.

scholarly journals Inactivity, age, and exercise: single-muscle fiber power generation

2013 ◽  
Vol 114 (1) ◽  
pp. 90-98 ◽  
Author(s):  
Jong-Hee Kim ◽  
LaDora V. Thompson
Keyword(s):  
Young Adult ◽  
Peak Power ◽  
Weight Bearing ◽  
Type I ◽  
Type Ii ◽  
Middle Aged ◽  
Adult Rats ◽  
Maximal Force ◽  
Old Rats ◽  
Type I Fibers

We examined the effects of mild therapeutic exercise during a period of inactivity on size and contractile functions of myosin heavy chain (MHC) type I ( n = 204) and type II ( n = 419) single fibers from the medial gastrocnemius in three age groups. Young adult (5–12 mo), middle-aged (24–31 mo), and old (32–37 mo) F344BNF1 rats were assigned to one of three groups: weight-bearing control, non-weight bearing (NWB), and NWB plus exercise (NWBX). Fourteen days of hindlimb suspension were applied in NWB rats. The NWBX rats exercised on the treadmill for 15 min, four times a day, during the period of NWB. The NWBX did not improve peak power, but increased normalized power of MHC type I fibers in young adult rats. In MHC type II fibers, NWBX did not change peak power, isometric maximal force, Vmax, and fiber size from young adult and middle-aged rats. NWBX did not improve peak power and isometric maximal force and showed a dramatic decline in Vmax and normalized power in the old rats. Collectively, mild treadmill exercise during a period of inactivity does not improve peak power of MHC type I or type II fiber from the gastrocnemius in young, middle-aged, and old rats. However, NWBX is beneficial in enhancing normalized power of MHC type I fibers in young adult rats, most likely due to the stimulus intensity and the ability of the individual fibers to adapt to the stimulus. In contrast, several factors, such as impaired adaptation potential, inappropriate exercise intensity, or increased susceptibility to muscle damage, may contribute to the lack of improvement in the older rats.

Association of insulin-like growth factor mRNA expressions with muscle regeneration in young, adult, and old rats

1997 ◽  
Vol 273 (1) ◽  
pp. R353-R358 ◽  
Author(s):  
D. R. Marsh ◽  
D. S. Criswell ◽  
M. T. Hamilton ◽  
F. W. Booth
Keyword(s):  
Young Adult ◽  
Growth Factor ◽  
Mrna Expression ◽  
Tibialis Anterior ◽  
Tibialis Anterior Muscle ◽  
Insulin Like Growth Factor ◽  
Adult Rats ◽  
Young Rats ◽  
Igf I ◽  
Old Rats

The purpose of this study was to determine whether impaired regeneration of skeletal muscle in old rats can be attributed to diminished expression of insulin-like growth factor (IGF) mRNAs. Fischer 344 male rats aged 2 (young), 12 (adult), and 24 mo (old) were given an injection of the myotoxic anesthetic, bupivacaine, into the left tibialis anterior muscle. Muscle mass and protein concentration recovered to contralateral control values by 28 days in young, but not adult or old rats. The temporal and maximal expressions of IGF-I mRNA were similar during recovery from bupivacaine on days 5 and 10 in young, adult, and old rat muscles. IGF-I mRNA levels were reduced toward control levels in young rats by 15 days, but remained elevated in adult and old rats. IGF-I receptor mRNA in bupivacaine-injected muscle of old rats was elevated significantly higher than injected muscle of young and adult rats at recovery day 5. Five days after bupivacaine injection, IGF-II mRNA was increased 46-fold in young rats but was only increased fourfold in adult rats. Thereafter, IGF-II mRNA expression was similar for young, adult, and old rats at 10 and 15 days of recovery. In summary, we demonstrate that impaired regeneration of the tibialis anterior muscle in adult or old rats after bupivacaine-induced damage is associated with a prolonged elevation of IGF-I mRNA expression and/or diminished initial IGF-II mRNA expression.

scholarly journals Hypertension in Prenatally Undernourished Young-Adult Rats Is Maintained by Tonic Reciprocal Paraventricular–Coerulear Excitatory Interactions

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3568
Author(s):  
Bernardita Cayupe ◽  
Carlos Morgan ◽  
Gustavo Puentes ◽  
Luis Valladares ◽  
Héctor Burgos ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Young Adult ◽  
Binding Sites ◽  
Systolic Pressure ◽  
Adult Rats ◽  
Excitatory Pathways ◽  
Induced Hypertension ◽  
Prenatal Undernutrition ◽  
Number Of Cells

Prenatally malnourished rats develop hypertension in adulthood, in part through increased α1-adrenoceptor-mediated outflow from the paraventricular nucleus (PVN) to the sympathetic system. We studied whether both α1-adrenoceptor-mediated noradrenergic excitatory pathways from the locus coeruleus (LC) to the PVN and their reciprocal excitatory CRFergic connections contribute to prenatal undernutrition-induced hypertension. For that purpose, we microinjected either α1-adrenoceptor or CRH receptor agonists and/or antagonists in the PVN or the LC, respectively. We also determined the α1-adrenoceptor density in whole hypothalamus and the expression levels of α1A-adrenoceptor mRNA in the PVN. The results showed that: (i) agonists microinjection increased systolic blood pressure and heart rate in normotensive eutrophic rats, but not in prenatally malnourished subjects; (ii) antagonists microinjection reduced hypertension and tachycardia in undernourished rats, but not in eutrophic controls; (iii) in undernourished animals, antagonist administration to one nuclei allowed the agonists recover full efficacy in the complementary nucleus, inducing hypertension and tachycardia; (iv) early undernutrition did not modify the number of α1-adrenoceptor binding sites in hypothalamus, but reduced the number of cells expressing α1A-adrenoceptor mRNA in the PVN. These results support the hypothesis that systolic pressure and heart rate are increased by tonic reciprocal paraventricular–coerulear excitatory interactions in prenatally undernourished young-adult rats.

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