• Toxicological Research
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• v.33 no.2
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• pp.157-164
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• 2017

This study was to evaluate the age-dependent effects of caffeine exposure on the long bones and reproductive organs using male rats. A total of 15 immature male rats and 15 young adult male rats were allocated randomly to three groups: a control group and two groups fed caffeine with 120 and 180 mg/kg/day for 4 weeks. Exposure to caffeine at either dose significantly reduced body weight gain; a proportional reduction in muscle and fat mass in immature animals, whereas a selective reduction in fat mass with relatively preserved muscle mass in young adult animals. The long bones of immature rats exposed to caffeine were significantly shorter and lighter than those of control animals along with decreased bone minerals. However, there was no difference in the length or weight of the long bones in young adult rats exposed to caffeine. Exposure to caffeine reduced the size and absolute weight of the testes significantly in immature animals in comparison to control animals, but not in young adult animals exposed to caffeine. In contrast, the adrenal glands were significantly heavier in caffeine-fed young adult rats in comparison to control animals, but not in caffeine-fed immature rats. Our results clearly show that the negative effects of caffeine on the long bones and testes in rats are different according to the age of the rat at the time of exposure, and might therefore be caused by changes to organ sensitivity and metabolic rate at different developmental stages. Although the long bones and testes are more susceptible to caffeine during puberty, caffeine has negative effects on body fat, bone minerals and the adrenal glands when exposure occurs during young adulthood. There is a need, therefore, to educate the public the potential dangers of caffeine consumption during puberty and young adulthood.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.229-236
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• 2000

The synthesis of steroid hormone starts from cholesterol. Steroidogenic acute regulatory protein (StAR) acutely transfers cholesterol from the outer mitochondrial membrane to the inner in the early step of steroidogenesis. Many kinds of steroid hormone are mainly synthesized in adrenal grand, ovary, and testis. Among the steroid hormone, testosterone is synthesized in Leydig cells of the testis, the production of testosterone significantly increases in adult testis after puberty onset. Therefore, we think that the expression of StAR mRNA in testis will change according to the testicular development. The aim of this study is to determine the distribution of StAR mRNA in immature and adult rat testes and to confirm the functions of StAR in these testes. Thus, in situ hybridization was used in rat testes of the 2, 4, and 10 weeks of age. StAR mRNA was expressed in Leydig cells. Positive signals of StAR mRNA were weakly detected in Leydig cells of the 2 weeks of age. But, StAR mRNA was strongly expressed in Leydig cells of the 4 and 10 weeks of age, where steroidogenesis actively occur. In our results, the pattern of StAR mRNA expression was similar to the pattern of testosterone production in immature and adult rat testes. In conclusion, we can suggest that StAR acts as an important factor to regulate the synthesis of testosterone in Leydig cells of the rat testis.

• Development and Reproduction
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• v.24 no.4
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• pp.263-275
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• 2020

The proper administration of melatonin has well been documented to induce testicular regression in seasonal breeding animals. The subcutaneous injections of melatonin in the afternoon, not in the morning, consistently occurred testicular involution in the male Syrian (golden) hamsters whose reproductive activity is regulated by the photoperiod. But the effects of daily melatonin via gavage have not been estimated. Golden hamsters housed in long photoperiod (LP) were divided into 5 groups: the control animals housed in LP or in short photoperiod (SP) and animals treated daily with low (15 ㎍), middle (150 ㎍), and high dosages (1,500 ㎍) of pure melatonin by using gavage in the evening for 8 weeks. As results, LP control animals had large testes and SP controls displayed small and entirely regressed testes. The animals treated with various dosages of melatonin showed collectively degenerating effects on the weights of testes, epididymides, and seminal vesicles in the middle and high dosage groups, with the individual differences as well. The high dosages induced testicular regression in more proportion than the middle dosages did. The low dosage had large testes like the LP control animals. The small and inactive testes shown in some animals of both middle and high groups presented the complete regression as those of the animals maintained in SP. These results strongly suggest that the administrations of melatonin lead to testicular involution in the male golden hamsters when it is administered through gavage.

• Journal of Life Science
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• v.9 no.4
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• pp.460-465
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• 1999

In the giant freshwater prawn Macrobrachium rosenbergii, the paired testes were united by the testes bridge in a H-shape. During mating male discharged two hemispermtophores from right and left genital pore and they were joined and formed a compound spermatophore in peach shape. Hemispermatophore was considered to be produced at proximal and middle vas deferens region. The compound spermatophore consisted of an eosinophilic inner matrix, a basophilic outer matrix and paired sperm mass burried in the basophilic matrix. The size of compound spermatophore was 6.4∼ 9.3 mm in length and 2.4∼5.1 mm in width regardless of carapace length. After the spermatophore was deposited on female's ventral sternum behind of 5th pereiopod, it was moved to the ventral surface of 3rd and 4th pereiopods by means of the beating of male's 1st and 2nd pleopods.

• Development and Reproduction
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• v.23 no.2
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• pp.101-110
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• 2019

Melatonin is a pineal hormone that is synthesized and released at night under the light and dark cycles of a day. Its effects on the reproductive activities have well been established by the administration through various routes in photoperiodic animals. It was also identified in plants and named phytomelatonin. The capacity of the phytomelatonin was investigated in this investigation whether it affects the reproductive function in male golden hamster. As expected, animals housed in long photoperiod (long photoperiod, LP>12.5 hours of lights in a day) had large testes and animals kept in short photoperiod ($$SP{\leq_-}12.5$$ hours of lights in a day) showed remarkably reduced testes. The dietary supplement with melatonin itself induced the complete involution of testes. Pistachios that were reported to contain a large amount of melatonin demonstrated no effects at all in male golden hamsters. These results suggest that dietary supplement containing melatonin-rich foodstuff used in this investigation may not be enough to affect the reproductive endocrine system in male golden hamsters.

• Clinical and Experimental Reproductive Medicine
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• v.26 no.1
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• pp.103-109
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• 1999

Objective: Heat shock protein 70-2 (Hsp70-2) gene knockout mice are found to have premeiotic arrest at the primary spermatocyte stage with a complete absence of spermatids and spermatozoa. This observation led to the hypothesis that hspA2 may be disrupted in human testes with abnormal spermatogenesis. To test this hypothesis, we studied the mRNA expression of hspA2 in infertile men with azoospermia. Design: The mRNA expression were analyzed by competitive RT-PCR among testes with normal spermatogenesis, pachytene spermatocyte arrest, and sertoli-cell only syndrome. Materials and methods: Testicular biopsy was performed in men with azoospermia (n=15). Specimens were subdivided into three groups: (group 1) normal spermatogenesis (n=5), (group 2) spermatocyte arrest (n=5), (group 3) Sertoli-cell only syndrome (n=5). Total RNA was extracted by Trizol reagent. Total extracted RNA was reverse transcribed into cDNA and amplified by PCR using specific primers for hspA2 target cDNAs. A competitive cDNA fragment was constructed by deleting a defined fragment from the target cDNA sequence, and then coamplified with the target cDNA for competitive PCR. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene was used as an internal control. Results: On Competitive RT-PCR analyses for hspA2 mRNA, significant amount of hspA2 expression was observed in group 1, whereas a constitutively low level of hspA2 was expressed in groups 2 and 3. Conclusion(s): The study demonstrates that the hspA2 gene expression is down-regulated in human testes with abnormal spermatogenesis, which in turn suggests that hspA2 gene may play a specific role during meiosis in human testes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.10
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• pp.199-203
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• 2016

Apolipophorin-III (apoLp-III) was isolated and purified from the last larval hemolymph of Galleria mellonella by KBr gradient ultracentrifugation and gel chromatography (Sephadex G-100). After KBr gradient ultracentrifugation, the lipophorin-free fractions were used as the samples for gel chromatography. The purity of the finally purified apoLp-III was confirmed by SDS-PAGE after gel chromatography. In this study, we found that apoLp-III is taken up into the adult testes in Galleria mellonella. The testes were dissected from day-1 or -2 adults in cold Ringer's solution and used for tissue culture. The protein moiety of apoLp-III was labeled with FITC dissolved in dimethyl sulfoxide (DMSO) at room temperature under conditions of continuous stirring for 1 h. The FITC-labeled apoLp-III was purified with a Sephadex G-25 PD-10 column. The tissues of the adult testes were incubated at room temperature for 30 min with fluorescein isothiocyanate (FITC)-labeled apoLp-III. Fluorescein microscopy and sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis (PAGE) revealed that the adult testis tissues internalize the FITC-labeled apoLp-III. The results showed that apoLp-III is taken up by the adult testes.

• Parasites, Hosts and Diseases
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• v.22 no.1
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• pp.99-101
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• 1984

Oochoristica pauriensis n.sp. has been described and figured from Hemidactylus brooki (Gray) and H. flaviviridis (Ruppell) on size of strobila, scolex, suckers, testes, ovary, eggs and oncosphere, and number of testes. The new specIes has been compared with close species.

• The Journal of Korean Medicine
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• v.25 no.4
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• pp.90-94
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• 2004

Objective : This study was conducted to investigate the effects of Panax Ginseng (인삼) on the sperm motility and spermatogenesis in the male rat. Methods : We used 8-week-old Sprague-Dawley rats, and administered the extract powder of Panax Ginseng to 5 rats (treated group) and normal saline (control group) once a day for 28 days. We isolated their testes surgically, then observed the change of the body weights before and after administration of Panax Ginseng extracts and normal saline. We observed the weight of the testes, epididymis, vascular gland, and prostate. Also, we examined the total, normal motile sperm concentration, and the concentration of testicular catalase and peroxidase. Results : We found that the concentration of normal, motile sperm in the testes of the Panax Ginseng group showed a significant difference compared with the control group. The angiogenesis of the seminiferous tubule was increased and the increasement of the number of spermatogonia, primary and secondary spermatocyte was observed in the Panax Ginseng group through a microscope. The body weight, the weight of the testes, epididymis, prostate and the concentration of testicular catalase and peroxidase were higher in the Panax Ginseng group but showed no significant difference. Conclusion : This study shows that Panax Ginseng may have an effect on the morphology and motility of sperm, the important factor in male fertility, and can promote the concentration of antioxidants, catalase and peroxidase, which is the important factor in spermatogenesis.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.1
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• pp.75-81
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• 1994

To elucidate the relationship between steroidogenesis and sex differentiation in the duck, plasma, testicular and ovarian testosterone, estradiol-$17{\beta}$ and progesterone concentration in male and female embryo of day 11 to 27 (just before hatching) of incubation and in 1- to 7-day-old male and female duckling were investigated by radioimmunoassays. Plasma estradiol-$17{\beta}$ concentration in female embryos declined from very high at days 11 and 15 of incubation and remained at low levels after hatching. Male plasma estradiol-$17{\beta}$ concentration were always lower than those of the female throughout this period. Plasma testosterone and progesterone concentrations in both sexes were low during the embryonic stage, but then increased to peaks 3 days and 1 day after hatching, respectively. Estradiol-$17{\beta}$ contents were much higher in the left ovary than the right ovary or testes throughout the experimental period. The estradiol-$17{\beta}$ content of the left ovary was very high at day 15 of incubation, and decreased gradually thereafter. Both in right ovary and testes, estradiol-$17{\beta}$ contents were always low. Testosterone and progesterone contents in the left ovary were low from day 11 to 23 of incubation, and reached a peak 1 day after hatching. Progesterone content in the right ovary and testes were low levels over time period examined. Testosterone and progesterone contents were much higher in the left ovary than the right ovary and testes. The present results clearly demonstrate that the capacity of the embryonic left ovary of duck to synthesize estradiol-$17{\beta}$ and testosterone is much higher than that of the embryonic testis. It is suggested that estrogen secreted from the embryonic ovary earlier than day 15 of incubation has an important role in female sexual differentiation in the duck, and the sex of the avian species is basically male with homozygous sex chromosome (ZZ).