Age-related changes in the feedback regulation of gonadotrophin secretion in the immature and adult male rabbit

1982 ◽  
Vol 100 (1) ◽  
pp. 18-24 ◽  
Author(s):  
M. Berger ◽  
Ch. Jean-Faucher ◽  
M. De Turckheim ◽  
G. Veyssière ◽  
CI. Jean
Keyword(s):  
Body Weight ◽  
Negative Feedback ◽  
Adult Male ◽  
Feedback Regulation ◽  
Adult Males ◽  
Age Related ◽  
Gonadotrophin Secretion ◽  
Age Dependent ◽  
Different Doses ◽  
Age Related Changes

Abstract. Male rabbits were castrated at infantile (30 days), peripubertal (60 days) and adult (7–8 months) stages. Two different doses of testosterone were injected 10 days after castration (5 injections at 12 h intervals). Plasma LH and FSH were determined by RIA 1,5 and 10 days after castration and 1 h after the last injection of testosterone. The response of both gonadotrophins to castration was age-dependent. In 30 day old castrated males LH was not significantly modified and FSH had increased only 10 days after castration. In 60 day old and adult males FSH and LH levels were increased 24 h after castration and continued to rise as time progressed. For both gonadotrophins, the response of adult males to castration was higher than that of immature animals. At all stages studied, the highest dose of testosterone (250 μg/kg body weight) depressed post-castration LH and FSH levels. Twenty-five μg of testosterone per kg body weight was effective to depress LH levels only in 30 day old males, suggesting a change in the hypothalamic-pituitary unit to the negative feedback of androgens. These findings suggest that there are marked changes in the hypothalamic-pituitary unit around the beginning of the peripubertal stage. These changes could play a determinant role in the onset of puberty.

Age-related changes in the TRB and IGH repertoires in healthy adult males and females

2021 ◽  
Author(s):  
Mingxing Gong ◽  
Xueying Li ◽  
Anqi Zheng ◽  
Hongxu Xu ◽  
Shi Xie ◽  
...  
Keyword(s):  
Healthy Adult ◽  
Adult Males ◽  
Age Related ◽  
Males And Females ◽  
Age Related Changes

Age-dependent alterations in Ca2+ homeostasis: role of TRPV5 and TRPV6

2006 ◽  
Vol 291 (6) ◽  
pp. F1177-F1183 ◽  
Author(s):  
Monique van Abel ◽  
Sylvie Huybers ◽  
Joost G. J. Hoenderop ◽  
Annemiete W. C. M. van der Kemp ◽  
Johannes P. T. M. van Leeuwen ◽  
...  
Keyword(s):  
Vitamin D ◽  
Mrna Levels ◽  
Serum Osteocalcin ◽  
Intestinal Epithelial ◽  
Receptor Mrna ◽  
Age Related ◽  
Age Dependent ◽  
Elder People ◽  
Age Related Changes

Aging is associated with alterations in Ca2+ homeostasis, which predisposes elder people to hyperparathyroidism and osteoporosis. Intestinal Ca2+ absorption decreases with aging and, in particular, active transport of Ca2+ by the duodenum. In addition, there are age-related changes in renal Ca2+ handling. To examine age-related changes in expression of the renal and intestinal epithelial Ca2+ channels, control (TRPV5+/+) and TRPV5 knockout (TRPV5−/−) mice aged 10, 30, and 52 wk were studied. Aging of TRPV5+/+ mice resulted in a tendency toward increased renal Ca2+ excretion and significantly decreased intestinal Ca2+ absorption, which was accompanied by reduced expression of TRPV5 and TRPV6, respectively, despite increased serum 1,25(OH)2D3 levels. Similarly, in TRPV5−/− mice the existing renal Ca2+ loss was more pronounced in elder animals, whereas the compensatory intestinal Ca2+ absorption and TRPV6 expression declined with aging. In both mice strains, aging resulted in a resistance to 1,25(OH)2D3 and diminished renal vitamin D receptor mRNA levels, whereas serum Ca2+ levels remained constant. Furthermore, 52-wk-old TRPV5−/− mice showed severe hyperparathyroidism, whereas PTH levels in elder TRPV5+/+ mice remained normal. In 52-wk-old TRPV5−/− mice, serum osteocalcin levels were increased in accordance with the elevated PTH levels, suggesting an increased bone turnover in these mice. In conclusion, downregulation of TRPV5 and TRPV6 is likely involved in the impaired Ca2+ (re)absorption during aging. Moreover, TRPV5−/− mice likely develop age-related hyperparathyroidism and osteoporotic characteristics before TRPV5+/+ mice, demonstrating the importance of the epithelial Ca2+ channels in Ca2+ homeostasis.

Age Related Changes in Protein C Activity in Healthy Adult Males

1991 ◽  
Vol 65 (03) ◽  
pp. 326-327 ◽  
Author(s):  
R C Tait ◽  
Isobel D Walker ◽  
S I A Islam ◽  
R Mitchell ◽  
J A Conkie ◽  
...  
Keyword(s):  
Protein C ◽  
Healthy Adult ◽  
Adult Males ◽  
Age Related ◽  
Protein C Activity ◽  
Age Related Changes

scholarly journals Spermidine protects from age-related synaptic alterations at hippocampal mossy fiber-CA3 synapses

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Marta Maglione ◽  
Gaga Kochlamazashvili ◽  
Tobias Eisenberg ◽  
Bence Rácz ◽  
Eva Michael ◽  
...  
Keyword(s):  
Molecular Basis ◽  
Memory Impairment ◽  
Mossy Fiber ◽  
Long Term Potentiation ◽  
Age Related ◽  
Term Potentiation ◽  
Hippocampal Synapses ◽  
Age Dependent ◽  
Age Related Changes

AbstractAging is associated with functional alterations of synapses thought to contribute to age-dependent memory impairment (AMI). While therapeutic avenues to protect from AMI are largely elusive, supplementation of spermidine, a polyamine normally declining with age, has been shown to restore defective proteostasis and to protect from AMI in Drosophila. Here we demonstrate that dietary spermidine protects from age-related synaptic alterations at hippocampal mossy fiber (MF)-CA3 synapses and prevents the aging-induced loss of neuronal mitochondria. Dietary spermidine rescued age-dependent decreases in synaptic vesicle density and largely restored defective presynaptic MF-CA3 long-term potentiation (LTP) at MF-CA3 synapses (MF-CA3) in aged animals. In contrast, spermidine failed to protect CA3-CA1 hippocampal synapses characterized by postsynaptic LTP from age-related changes in function and morphology. Our data demonstrate that dietary spermidine attenuates age-associated deterioration of MF-CA3 synaptic transmission and plasticity. These findings provide a physiological and molecular basis for the future therapeutic usage of spermidine.

Effect of Paracetamol on Sperm Biological Parameters and Testosterone Level in Albino Male Mice

2021 ◽  
pp. 51-57
Author(s):  
Habiba Eljaafari ◽  
Zainab EL Mabrouk ◽  
Marwan Rashrash
Keyword(s):  
Body Weight ◽  
Adult Male ◽  
Testosterone Level ◽  
Sperm Morphology ◽  
Sperm Parameters ◽  
Male Mice ◽  
Once Daily ◽  
High Doses ◽  
Fertilizing Capability ◽  
Different Doses

Backgrounds and objectives. The wide use of paracetamol at high doses was found to alter sperm parameters especially sperm morphology, and thus its fertilizing capability. Therefore, the present study was designed to use different doses of paracetamol to identify its effect on sperm parameters and testosterone levels in adult male mice. Methods. Forty adult male albino mice were divided into four equal groups, the first group injected with distilled water, the three treated groups injected with different doses of paracetamol (20, 40, 80 mg/kg body weight /day) over a period of 42 days. All doses were given once daily via intraperitoneal injection. Results. The results showed that paracetamol causes a significant decrease in body weight, non-significance effect on sperm parameters at doses of 20 and 40 mg/kg, while it led to a significant effect on sperm parameters at a dose of 80 mg/kg. Also, there was no difference in testosterone level between control and the treated groups (20 and 40mg/kg). But it showed a significant decrease in testosterone level at dose 80 mg/kg treated groups. Conclusion. It is considered safe to use paracetamol at doses 20 and 40 mg/kg but the dose 80 mg/kg has adverse effects on sperm parameters and testosterone level.

Age-Related Changes in Distribution of Body Weight on Soles of Feet for Selected Actions and Postures

1997 ◽  
Vol 85 (3_suppl) ◽  
pp. 1263-1271 ◽  
Author(s):  
Toshiaki Yanagida ◽  
Takaaki Asami
Keyword(s):  
Body Weight ◽  
Weight Distribution ◽  
Healthy Subjects ◽  
Age Groups ◽  
The Body ◽  
The Other ◽  
Elderly Subjects ◽  
Age Related ◽  
Soles Of The Feet ◽  
Age Related Changes

We investigated age-related changes in the distribution of body weight on soles of feet in 878 healthy subjects ranging from 5 to 80 years of age. By modifying Morton's Staticometer, we constructed an instrument for measuring body-weight distribution over three areas of soles of the feet, the big toe (inner forefoot), the other four toes combined (outer forefoot) and the heels for both feet, thus a total of six areas. The weights in the six areas were recorded at the completion of nine selected actions and postures. We observed that for inhaling and exhaling standing postures, generally younger subjects had a ratio close to 1:2:3 for weights recorded for the inner toe:outer toes:heels as observed by Morton, but elderly subjects had a smaller value than 3 for the heel. The body-weight distribution tended to shift from heels to outer toes across age groups, which was more distinctly observed in women than in men.

scholarly journals Age-related changes of malondialdehyde, body weight and organ weight in male mice

2018 ◽  
Vol 37 (2) ◽  
pp. 115
Author(s):  
Ika Fidianingsih ◽  
Dwi Nur Ahsani
Keyword(s):  
Body Weight ◽  
Free Radicals ◽  
Venous Blood ◽  
Relative Weight ◽  
Male Mice ◽  
Serum Free ◽  
Organ Weights ◽  
Age Related ◽  
Experimental Animal Study ◽  
Age Related Changes

Introduction<br />Aging is characterized by gradual impairment in all physiological functions. Increases in free radicals and changes in organ morphology occur with aging. The purpose of this study was to determine age-related changes in serum free radicals, body weight, organ weights, and relative organ weights in male mice. <br /><br />Methods<br />An experimental animal study was performed on 25 male mice (Mus musculus), which were randomized into 5 groups according to age at termination, i.e. 12 (group K1), 24 (K2), 32 (K3), 40 (K4) and 48 weeks (K5), respectively. Retro-orbital venous blood was taken for examination of malondialdehyde (MDA) levels. After termination, liver, heart, kidneys, testes, brain, thymus and spleen were weighed using an analytical balance. ANOVA and Kruskal Wallis tests were used to analyze the data, with p&lt;0.05 being considered significant. <br /><br />Results<br />Significant changes were found with age in serum MDA level (p=0.000), body weight (p=0.000), and weights of all organs except thymus (p&gt;0.05) (liver p=0.023, heart p=0.000, kidneys p=0.002, testes p=0.000, brain p=0.012 and spleen p=0.006). Significant changes in relative weight of brain (p=0.001) and spleen (p=0.049) were also found with age. <br /><br />Conclusion<br />This study demonstrated increases in serum MDA levels, body weight, and weights of the liver, heart, kidneys, testes, brain and spleen with age. Peak increases in weights of kidneys and thymus were found earlier than those in MDA levels and weights of other organs.

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