scholarly journals Age-Related Changes in Hepatic Activity and Expression of Detoxification Enzymes in Male Rats

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Erika Vyskočilová ◽  
Barbora Szotáková ◽  
Lenka Skálová ◽  
Hana Bártíková ◽  
Jitka Hlaváčová ◽  
...  
Keyword(s):  
Antioxidant Enzymes ◽  
Specific Activity ◽  
Detoxification Enzymes ◽  
Male Rats ◽  
Cellular Functions ◽  
Metabolizing Enzymes ◽  
Age Related ◽  
Male Wistar Rats ◽  
Old Rats ◽  
Specific Activities

Process of aging is accompanied by changes in the biotransformation of xenobiotics and impairment of normal cellular functions by free radicals. Therefore, this study was designed to determine age-related differences in the activities and/or expressions of selected drug-metabolizing and antioxidant enzymes in young and old rats. Specific activities of 8 drug-metabolizing enzymes and 4 antioxidant enzymes were assessed in hepatic subcellular fractions of 6-week-old and 21-month-old male Wistar rats. Protein expressions of carbonyl reductase 1 (CBR1) and glutathioneS-transferase (GST) were determined using immunoblotting. Remarkable age-related decrease in specific activities of CYP2B, CYP3A, and UDP-glucuronosyl transferase was observed, whereas no changes in activities of CYP1A2, flavine monooxygenase, aldo-keto reductase 1C, and antioxidant enzymes with advancing age were found. On the other hand, specific activity of CBR1 and GST was 2.4 folds and 5.6 folds higher in the senescent rats compared with the young ones, respectively. Interindividual variability in CBR1 activity increased significantly with rising age. We suppose that elevated activities of GST and CBR1 may protect senescent rats against xenobiotic as well as eobiotic electrophiles and reactive carbonyls, but they may alter metabolism of drugs, which are CBR1 and especially GSTs substrates.

Effects of trenbolone acetate and testosterone on growth and on plasma concentrations of corticosterone and ACTH in rats

1990 ◽  
Vol 126 (3) ◽  
pp. 461-466 ◽  
Author(s):  
M. N. Sillence ◽  
R. G. Rodway
Keyword(s):  
Weight Gain ◽  
Growth Response ◽  
Plasma Concentrations ◽  
Female Rats ◽  
Male Rats ◽  
Adrenal Weight ◽  
Trenbolone Acetate ◽  
Male And Female Rats ◽  
Age Related ◽  
Old Rats

ABSTRACT The effects of trenbolone acetate (TBA) on growth and on plasma concentrations of corticosterone were examined in male and female rats. At 5 weeks of age, rats were injected with TBA (0·8 mg/kg) dissolved in peanut oil, or with oil alone, daily for 10 days. In female rats, TBA caused an increase in weight gain (20–38%), a reduction in adrenal weight (19%) and a reduction in plasma concentrations of corticosterone (55%). In contrast, TBA-treated male rats showed no significant increase in weight gain, no significant change in adrenal weight and no reduction in plasma concentrations of corticosterone. The mechanism by which adrenal activity was suppressed in TBA-treated female rats was examined and the response compared with that to testosterone. Female rats (8 weeks old) were injected daily either with oil vehicle, TBA (0·8 mg/kg) or testosterone propionate (0·8 mg/kg). Testosterone increased weight gain (24%), but the growth response to TBA treatment was significantly greater (97%). A reduction in plasma concentrations of corticosterone (45%) was again observed in response to TBA. However, testosterone increased plasma concentrations of corticosterone (52%) above those of control values. Neither androgen affected plasma concentrations of ACTH. Finally, the effects of TBA were examined in 6-week-old female rats, to characterize further the apparent age-related increase in responsiveness. The growth response of 6-week-old rats (60–74%) was intermediate between that seen in 5- and 8-week-old animals. It is concluded that part of the anabolic activity of TBA may be related to a reduction in circulating concentrations of corticosterone. The effect of TBA on corticosterone concentrations differs from that of the natural androgen, testosterone, and does not appear to be mediated by a reduction in plasma concentrations of ACTH. Journal of Endocrinology (1990) 126, 461–466

Circulating hyaluronan levels in the rodent: effects of age and diet

1995 ◽  
Vol 268 (4) ◽  
pp. C952-C957 ◽  
Author(s):  
J. Yannariello-Brown ◽  
S. H. Chapman ◽  
W. F. Ward ◽  
T. C. Pappas ◽  
P. H. Weigel
Keyword(s):  
Fish Meal ◽  
Caloric Intake ◽  
Protein Source ◽  
Male Rats ◽  
Semisynthetic Diet ◽  
Fischer 344 ◽  
Age Related ◽  
Old Rats ◽  
Ad Libitum ◽  
Age Related Changes

Circulating hyaluronan (HA) levels were investigated as a function of age and diet in Fischer 344 male rats. A biphasic pattern of age-related changes was observed in rats fed ad libitum a diet in which the protein source was soya/fish meal. HA levels in 3- to 6- and 22- to 29-mo-old rats were not statistically different. However, HA levels in 12- to 20-mo-old rats were 10-29% of the levels in younger or aged adults. HA levels were also measured in rats fed ad libitum a semisynthetic diet in which the protein source was hydrolyzed casein. Whereas the two colonies exhibited similar biphasic age-related changes, HA levels differed 4- to 20-fold at every age examined. Caloric restriction affected HA levels in 19-mo-old casein-fed rats; HA levels were 2.3 times higher than age-matched controls and were not statistically different from young or aged animals. Serum and plasma HA levels were identical in the same individuals at all ages tested. These data suggest that HA turnover and metabolism in the rat are affected by age, dietary composition, and caloric intake.

Expression of acetylcholine receptor mRNAs in atrophying and nonatrophying skeletal muscles of old rats

1998 ◽  
Vol 85 (5) ◽  
pp. 1903-1908 ◽  
Author(s):  
Ronald R. Gomes ◽  
Frank W. Booth
Keyword(s):  
Skeletal Muscle ◽  
Acetylcholine Receptor ◽  
Biceps Brachii ◽  
Male Rats ◽  
Brown Norway ◽  
Mrna Levels ◽  
Adult Rats ◽  
Γ Subunit ◽  
Age Related ◽  
Old Rats

We examined the age-related association in skeletal muscle between atrophy and expression of mRNAs encoding both the γ-subunit of the nicotinic acetylcholine receptor (AChR), and myogenin, a transcription factor that upregulates expression of the γ-subunit promoter. Gastrocnemius and biceps brachii muscles were collected from young (2-mo-old), adult (18-mo-old), and old (31-mo-old) Fischer 344/Brown Norway F1 generation cross male rats. In the gastrocnemius muscles of old vs. young and adult rats, lower muscle mass was accompanied by significantly elevated AChR γ-subunit and myogenin mRNA levels. In contrast, the biceps brachii muscle exhibited neither atrophy nor as drastic a change in AChR γ-subunit and myogenin mRNA levels with age. Expression of the AChR ε-subunit mRNA did not change with age in either gastrocnemius or biceps brachii muscles. Thus changes in skeletal muscle AChR γ-subunit and myogenin mRNA levels may be more related to atrophy than to chronological age in old rats.

scholarly journals Moderate-intensity interval training (MIT) can protect rats against Methamphetamine –induced injuries

2021 ◽  
Author(s):  
Ahad Shafiei Bafti ◽  
Amir Hossein Haghighi ◽  
Roya Askari ◽  
Alireza Keyhani ◽  
Mahla sadat Nabavi Zadeh ◽  
...  
Keyword(s):  
Gene Expression ◽  
Antioxidant Enzymes ◽  
Spatial Memory ◽  
Interval Training ◽  
Saline Group ◽  
Neural System ◽  
Male Rats ◽  
Moderate Intensity ◽  
Morris Water Maze Test ◽  
Male Wistar Rats

Abstract Methamphetamine (METH) can cause neurotoxicity and increase the risk of neurodegenerative disorders such as Alzheimer disease and Parkinson disease. This study aimed to investigate the effect of moderate-intensity interval training (MIT) on gene expression and antioxidant status of the hippocampus of METH-dependent rats. Twenty-eight male Wistar rats were randomly divided into four equal groups (n=7): saline, METH, MIT, and METH+MIT. METH was injected intraperitoneally at 5 mg/kg for 21 days. The MIT (intermittent running) was performed on the treadmill 5 days a week for 8 weeks. Morris Water Maze test was performed to measure learning and memory. Then, the hippocampal tissue was extracted to evaluate changes in gene expression and biochemical enzymes. The data were analyzed using one-way and two-way ANOVA methods at P<0.05. The results showed that METH injection significantly reduced spatial memory and antioxidant enzymes and increased the expression of α-synuclein (α-syn), cyclin-dependent kinase 5 (CDK5), tau and phosphorylated tau (p-Tau) genes compared to the saline group. MIT significantly increased spatial memory and antioxidant enzymes. However, it reduced α-syn, CDK5, tau and p-tau expression. Thus, METH caused neural damage, and MIT could protect the neural system against METH-induced insults in male rats.

Old Rats Are More Susceptible to Induction of Benign Prostatic Hyperplasia (BPH) at Comparative to Young Mature

2021 ◽  
Vol 14 ◽  
Author(s):  
Vladimir G. Bespalov ◽  
Valerij A. Alexandrov ◽  
Alexander L. Semenov ◽  
Grigory V. Tochilnikov ◽  
Elena D. Ermakova ◽  
...  
Keyword(s):  
Metabolic Disorders ◽  
Serum Testosterone ◽  
The Body ◽  
Prostate Hyperplasia ◽  
Age Related ◽  
Low Concentrations ◽  
Male Wistar Rats ◽  
Old Rats ◽  
Intact Rats

Aims: The aim of the experiments was to find out the factors on which age-related sensitivity to the occurrence of BPH depends. Methods: 45 male Wistar rats aged 3 and 24 months were used. In each age group there were intact rats and animals with induced BPH (by surgical castration + testosterone injections, 25 mg/kg x 7). On the 36th day of the experiment, blood was taken from rats to determine serum testosterone, cholesterol, triglycerides and glucose; then the animals were autopsied, their prostates were weighed, and their morphology was studied. Results: Young mature intact rats had much higher testosterone levels (6.2±0.93 nmol/l) than old intact (3.8±0.55 nmol/l), while the ratio of prostate weight was inverse. The weight of the prostate and prostatic index in old rats with induced BPH was significantly higher not only in comparison with the old intact rats but also with young animals after BPH induction. Morphologically, the inflammatory foci were determined not only in the prostates of old rats, which induced BPH, but also in intact animals. Besides in old intact rats, the foci of prostate hyperplasia were often noted. Conclusions: Our experimental model indicates the important role of non-bacterial prostatitis in the pathogenesis of BPH. No metabolic disorders in BPH induction were revealed. The sensitivity of the prostate of old rats to BPH development is increasing despite the low concentrations of testosterone in the body. Age sensitivity to BPH is probably determined by a higher expression of androgen receptors in old animals.

Myoinositol biosynthesis by Sertoli cells, and levels of myoinositol biosynthetic enzymes in testis and epididymis

1979 ◽  
Vol 57 (6) ◽  
pp. 962-967 ◽  
Author(s):  
Ranga Robinson ◽  
Irving B. Fritz
Keyword(s):  
Sertoli Cells ◽  
Specific Activity ◽  
Primary Cultures ◽  
Defined Medium ◽  
Seminiferous Tubules ◽  
Chemically Defined Medium ◽  
Dibutyryl Cyclic Amp ◽  
Old Rats ◽  
Specific Activities ◽  
Germinal Cells

Levels of glucose-6-phosphate cyclase (myoinositol-1-phosphate synthase, EC 5.5.1.4) and myoinositol-1-phosphate phosphatase (myoinositol-1-phosphatase, EC 3.1.3.25) were determined in extracts of testes from 10-, 20-, and 30-day-old rats, and in extracts of Sertoli cells, germinal cells, and epididymides. The specific activity of the cyclase was approximately [Formula: see text] that of the phosphatase in all extracts found to contain either enzyme. Among cells in the testis examined, Sertoli cells had highest levels of enzymes required for inositol biosynthesis from glucose, while spermatocytes and round spermatids did not have detectable activity. Spermatozoa from the epididymis also had no detectable cyclase or phosphatase activity. In contrast, extracts of washed epididymides contained exceedingly high specific activities of these enzymes. Primary cultures of Sertoli cells, maintained in a chemically defined medium without added inositol, released inositol into the medium during three successive 24-h periods. The amounts released were greater in cells stimulated by dibutyryl cyclic AMP. Results were interpreted to indicate that inositol in the fluid of seminiferous tubules most probably originates from Sertoli cells, which synthesize inositol from glucose. Additional inositol in the fluid of epididymal tubules could readily be provided by metabolism of glucose by epididymal epithelial cells.

INITIALE VERTEILUNG VON RADIO-C IN UNREIFEN RATTEN NACH INFUSION PHYSIOLOGISCHER MENGEN VON TESTOSTERON-4-14C

1967 ◽  
Vol 54 (3) ◽  
pp. 557-567 ◽  
Author(s):  
K.-O. Mosebach ◽  
H. Jühe ◽  
W. Dirscherl
Keyword(s):  
Specific Activity ◽  
Male Rats ◽  
Injection Technique ◽  
Sprague Dawley ◽  
Immature Male ◽  
Target Organs ◽  
Sprague Dawley Rats ◽  
Specific Activities ◽  
Infusion Technique ◽  
Vesicle Secretion

ABSTRACT Over a period of 2 hours the distribution and the specific activities of 14C (dpm/mg C) in organs of immature male Sprague-Dawley rats were studied after infusion of testosterone-4-14C. Only in liver, adrenals, kidneys and lungs we found specific activities essentially higher than those of the blood. The values of testis, seminal vesicles, prostata, epididymis and penis were similar to blood. Corresponding to former experiments using injection technique the more physiological infusion technique did not show any accumulation of radioactivity in the target organs too. On the contrary the specific activity of the seminal vesicle secretion was clearly higher than those of the residue organ and the blood. In adrenals medulla contained more radioactivity than cortex, demonstrated by 3 different methods (combustion, extraction and histoautoradiography). The distributions of progesterone-4-14C and oestradiol-4-14C after infusion in immature male rats were similar to those of testosterone-4-14C. The latter did not show a striking affinity for uterus, vagina and ovaries after infusion into female immature rats.

Abated cardiovascular responses to chronic oral lisinopril treatment in conscious elderly rats

1999 ◽  
Vol 276 (5) ◽  
pp. R1408-R1415 ◽  
Author(s):  
Ruben Buñag ◽  
Jennifer Mellick ◽  
Brandy Allen
Keyword(s):  
Baroreflex Sensitivity ◽  
Cardiovascular Effects ◽  
Cardiovascular Responses ◽  
Male Rats ◽  
Adrenergic Blockade ◽  
Reflex Bradycardia ◽  
Age Related ◽  
Pressor Responses ◽  
Mean Pressure ◽  
Old Rats

To determine whether the cardiovascular effects of chronic treatment with lisinopril are age related, we compared baroreflex sensitivity and pressor responsiveness in 4-mo- and 21-mo-old male rats that had been given oral lisinopril daily for 4 wk. Reflex bradycardia elicited by elevating blood pressure with phenylephrine was stronger in 4-mo-old rats than it was in 21-mo-old rats and also stronger in lisinopril-treated rats than it was in untreated rats of the same age. Pressor responses to angiotensin or norepinephrine were recorded after combined cholinergic and β-adrenergic blockade and then analyzed not only as absolute but also as percent increases in mean pressure. Although pressor responses seemed to be slightly reduced by lisinopril when expressed as absolute increases in mean pressure, corresponding percent increases were always larger in 4-mo-old rats than they were in 21-mo-old rats and were clearly enhanced by lisinopril more in younger rats. The stronger overall enhancement of pressor responsiveness and reflex bradycardia in younger rats suggests that the cardiovascular effects of lisinopril diminish with advancing age.

scholarly journals Stereological analysis of hepatic fine structure in the Fischer 344 rat. Influence of sublobular location and animal age.

1978 ◽  
Vol 78 (2) ◽  
pp. 319-337 ◽  
Author(s):  
D L Schmucker ◽  
J S Mooney ◽  
A L Jones
Keyword(s):  
Endoplasmic Reticulum ◽  
Fine Structure ◽  
Surface Area ◽  
Structural Parameters ◽  
Male Rats ◽  
Ground Substance ◽  
Stereological Analysis ◽  
Fischer 344 ◽  
Age Related ◽  
Old Rats

Stereological analysis of hepatic fine structure in Fischer 344 male rats at 1, 6, 10, 16, 20, 25, and 30 mo of age revealed differences in the amounts and distributions of hepatocellular organelles as a function of sublobular location or animal age. Between 1 and 16 mo of age, both the centrolobular and periportal hepatocytes increased in volume by 65 and 35%, respectively. Subsequently, the cell volumes declined until the hepatocytes of 30-mo-old rats approached the size of those found in the youngest animals. Regardless of animal age, the centrolobular cells were consistently larger than the corresponding periportal hepatocytes. The cytoplasmic and ground substance compartments reflected similar changes in their volumes, although there was no significant alteration in the nuclear volume. The volumes of the mitochondrial and microbody compartments increased and decreased concomitant with the changes in average hepatocyte size. Both lobular zones in the 30-mo-old rats contained significantly smaller relative volumes of mitochondria than similar parenchyma in 16-mo-old animals. The volume density of the dense bodies (lysosomes) increased markedly in both lobular zones between 1 and 30 mo of age, confirming reports of an age-dependent increase in this organelle. The surface area of the endoplasmic reticulum in the centrolobular and periportal hepatocytes reached its maximum level in the 10-mo-old rats and subsequently declined to amounts which approximated those measured in the 1-mo-old animals. This age-related loss of intracellular membrane is attributable to a significant reduction in the surface area of the smooth-surfaced endoplasmic reticulum (SER) in animals beyond 16 mo of age. The amount of rough-surfaced endoplasmic reticulum (RER) in the periportal parenchymal cells was unaffected by aging, but the centrolobular hepatocytes of 30-mo-old animals contained 90% more RER than similar cells in the youngest rats. The centrolobular parenchyma contained more SER and the portal zones more RER throughout the age span studied. These quantitative data suggest that (a) certain hepatic fine structural parameters undergo marked changes as a function of animal age, (b) there exists a gradient in hepatocellular fine structure across the entire liver lobule, and (c) there are remarkable similarities in hepatocyte ultrastructure between very young and senescent animals, including cell size and the amount of SER.

Age-related changes of growth hormone secretory mechanisms in the rat pituitary gland

1991 ◽  
Vol 131 (2) ◽  
pp. 251-257 ◽  
Author(s):  
M. Parenti ◽  
D. Cocchi ◽  
G. Ceresoli ◽  
C. Marcozzi ◽  
E. E. Müller
Keyword(s):  
Growth Hormone ◽  
Male Rats ◽  
Lower Percentage ◽  
Aged Rats ◽  
Adult Rats ◽  
Infant Rats ◽  
Age Related ◽  
Rat Pituitary ◽  
Old Rats ◽  
Stimulation Of

ABSTRACT The mechanisms underlying the age-related decrease and increase in somatotroph responsiveness to growth hormone-releasing factor (GHRF) and somatostatin respectively were studied in rat pituitary membranes in vitro. Basal adenylate cyclase (AC) activity was similar in pituitary membranes from rats of 8 days (either sex) and male rats of 3 months, but it was almost threefold higher in membranes from male rats of 21–23 months. GHRF induced a lower percentage stimulation of AC activity in membranes from infant and old than adult rats. Somatostatin inhibited stimulation of AC induced by forskolin more effectively in membranes from adult than infant and old rats. In parallel experiments, since the tissue we used is formed by a mixed population of pituitary cells, we evaluated, for comparison, the effect on AC of neurohormones, i.e. vasoactive intestinal polypeptide (VIP) and dopamine which act primarily on lactotrophs. VIP induced a lower fold-stimulation of AC activity in membranes from infant and old than adult rats. Dopamine inhibited forskolin-induced stimulation of AC in the following rank order of magnitude: old, adult and infant rats, and was also more effective in inhibiting basal AC activity in old than in adult rats. The stimulatory and inhibitory G proteins (Gs and Gi) coupled to AC were measured indirectly by evaluating stimulatory and inhibitory effects of different concentrations of GTP on AC. GTP, at stimulatory concentrations, increased AC activity in membranes from infant and adult rats similarly whereas its effect was significantly greater in membranes from old rats. Conversely, GTP, at inhibitory concentrations, decreased AC activity similarly in membranes from adult and infant rats, whereas in old rats inhibition was apparent at more than a tenfold lower concentration of GTP. These data suggest (1) that the greater somatotroph sensitivity to GHRF in terms of GH secretion of the early postnatal period is not due to supersensitive GHRF receptors but rather may be accounted for, at least partially, by the low function of somatostatinergic receptors; (2) that the inability of GHRF to stimulate GH release in aged rats probably results from an uncoupling between the GHRF receptor and the G protein; and (3) that in aged rats the decreased ability of somatostatin to inhibit AC activity, in spite of the high Gi activity, results from a reduced number of somatotroph cells and, hence, receptors. Journal of Endocrinology (1991) 131, 251–257

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