Brown Norway rat에서 노화 간질세포에 미치는 LH와 thyroxine의 영향
Effects of Luteinizing and thyroid hormones on the aged leydig cells in brown Norway rats
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The present study was designed to investigate the possibility of restoring the testicular steroidogenic ability of the aged Brown Norway rats by administering luteinizing hormone (LH) and thyroxine (Thy). Rats of 3, 6, 12 months (M) of age (n = 8 per group) and four groups of 18 month old rats (n = 8 per group) were used. Eighteen month old rats were implanted subdermally with Alzet mini osmotic pumps containing saline (control), luteinizing hormone (LH, 24 μg/day), thyroxine (Thy, 5 μg/day) and LH and Thy (LH±Thy, 24 μg/day and 5 μg/day), respectively for four weeks (i.e testing was done at 19 months). The results showed that the testis volume was unchanged among all treatment groups. The number of Leydig cell per testis was not significantly different among all treatment groups. The average volume of a Leydig cell was significantly decreased at 12 months, and a further reduction was observed at 19 months (saline-treated); values for 19 month LH- and -LH±Thy-treated rats were not significantly lower than those at 3 and 6 months of age. Testosterone secretory capacity per testis and per Leydig cell in vitro were significantly reduced concomitantly with age advancement from 6 to 19 months (saline-treated) of age. These values of LH- and Thy-treated 19 month old rats were similar to those at 12 months. LH±Thy-treated rats were equally capable to 3 and 6 month old rats in producing testicular testosterone in vitro in response to LH. Serum testosterone was unchanged from 3M to 12 M rats but was reduced in 19M control rats. Both LH and Thy significantly raised these values above the 19M control levels, but they were still lower than the 3M through 12 M levels. Additionally, LH±Thy significantly raised the serum testosterone levels to those of 12M rats, but these values were significantly lower than those of 3M and 6M rats. In summary, the present study demonstrated that the exogenous supplementation of LH and Thy was effective in restoring the steroidogenic potential of the aged Leydig cells; the most effective treatment was LH±Thy, which upgraded the capacity of aged testes to those of 3 and 6 months.
Abstract
The present study was designed to investigate the possibility of restoring the testicular steroidogenic ability of the aged Brown Norway rats by administering luteinizing hormone (LH) and thyroxine (Thy). Rats of 3, 6, 12 months (M) of age (n = 8 per group) and four groups of 18 month old rats (n = 8 per group) were used. Eighteen month old rats were implanted subdermally with Alzet mini osmotic pumps containing saline (control), luteinizing hormone (LH, 24 μg/day), thyroxine (Thy, 5 μg/day) and LH and Thy (LH±Thy, 24 μg/day and 5 μg/day), respectively for four weeks (i.e testing was done at 19 months). The results showed that the testis volume was unchanged among all treatment groups. The number of Leydig cell per testis was not significantly different among all treatment groups. The average volume of a Leydig cell was significantly decreased at 12 months, and a further reduction was observed at 19 months (saline-treated); values for 19 month LH- and -LH±Thy-treated rats were not significantly lower than those at 3 and 6 months of age. Testosterone secretory capacity per testis and per Leydig cell in vitro were significantly reduced concomitantly with age advancement from 6 to 19 months (saline-treated) of age. These values of LH- and Thy-treated 19 month old rats were similar to those at 12 months. LH±Thy-treated rats were equally capable to 3 and 6 month old rats in producing testicular testosterone in vitro in response to LH. Serum testosterone was unchanged from 3M to 12 M rats but was reduced in 19M control rats. Both LH and Thy significantly raised these values above the 19M control levels, but they were still lower than the 3M through 12 M levels. Additionally, LH±Thy significantly raised the serum testosterone levels to those of 12M rats, but these values were significantly lower than those of 3M and 6M rats. In summary, the present study demonstrated that the exogenous supplementation of LH and Thy was effective in restoring the steroidogenic potential of the aged Leydig cells; the most effective treatment was LH±Thy, which upgraded the capacity of aged testes to those of 3 and 6 months.
참고문헌 (50)
- "Pituitary-testicular function chan-ges in hypo and hyperthyroid male rats. Acta Anat 98", pp.121~129 (1977)
- "Androgen supple-mentation in eugonadal men with osteoporosis-effects of 6347─ Effects of Luteinizing and Thyroid Hormones on the Aged Leydig Cells ─months of treatment on bone mineral density and cardio-vascular risks factors. Bone 118", 118, pp.171~177 (1996)
- "Effects of thyroid hormone on Leydig cell regene-ration in the adult rat following ethane dimethane sulpho-nate treatment. Biol Reprod 63", 63, pp.1115~1123 (2000)
- "Changes inthe testis interstitium of Sprague Dawley rats from birth tosexual maturity. Biol Reprod 62", 62, pp.158~168 (2000)
- "Effects of tri-iodothyronine on testicular interstitial cellsand androgen secretory capacity of the prepubertal rat. BiolReprod 63", 63, pp.493~502 (2000)
- "Age-related changes in reproductivehormones and in Leydig cell responsivity in the maleFisher 344 rat. I. Gerontology 34", pp.21~27 (1979)
- "Age-relateddecreased Leydig cell testosterone production in the BrownNorway Rat. J Androl 15", pp.551~557 (1994)
- "Increase in Leydig cell numberin testes of adult rats treated chronically with an excess ofhuman chronic gonadotropins. Biol Reprod 22", pp.383~391 (1980)
- "Centralhypothyroidism is associated with advanced age in maleFischer 344", N rats in vivo and in vitro studies. Endocr-inology 131, pp.131, 2672~
- "Stress-induced inhibition of the hypothala-mic-pituitary-thyroid axis is attenuated in the agedFischer 344", N male rat. Neuroendocrinology 62, 1995., pp.62, 506~513
- "t tests and intervals for comparisons suggestedby the data. Biometrics 31", pp.339~359 (1975)
- "1983. Effects of luteinizing hormone on Leydig cell struc-ture and testosterone secretion. Endocrinology 112", pp.1763~1769 (1983)
- "The age related decline of androgen levels in men: clinically significant?", 78, pp.763~768 (1996), W.B. SaundersCompany
- "Testosterone secretion inthe rat in response to chorionic gonadotrophin. Endocri-nology 102", pp.540~544 (1978)
- "Relevance of the rodent model to human agingstudies. Neurobiol Aging 12", pp.645~649 (1991)
- "The micro determination oftestosterone in human spermatic vein blood. J Clin Endoc-rinol 18", pp.966~971 (1958)
- "1993. Ultrastr-ucture and morphometry of testicular Leydig cells and theinterstitial components correlated with testosterone in ag-ing rats. Cell Tissue Res 271", pp.241~255 (1993)
- "Age related changes in the Leydigcell population", pp.24 703~712 (1981)
- "Measurement of plasma testo-sterone and androstenedione using electron capture gas-liquid chromatography. J Clin Invest 47", pp.38~47 (1968), Martin CE
- "Effect of aging on the volume struc-ture and total Leydig cell content of the human testis. Int.J. Fert. 19", pp.140~146 (1974)
- "Effect of age on testis delta-5B-hydroxysteroid dehydrogenase in the rat. Proc Soc ExpBiol Med 145", pp.1211~1214 (1974)
- "Age related decline in the steroidogenivcapacity of isolated rat Leydig cells a defect in cholesterolmobilization and processing. J Steroid Biochem MolecBiol 46", pp.39~47 (1993)
- "l. testosterone and adenosine 3′5′-monophosphate responses to gonadotropin stimulation inrats. Steroids 35", muro(e), pp.653~663 (1980)
- "steroidogenic acute regulatory protein(StAR) and cholesterol side-chain cleavage enzyme", 22, pp.149~156 (2001), and cholesterol side-chaincleavage enzyme. J. Androl. 22
- "Are Leydig cell steroidogenicenzymes differentially regulated with aging? J Androl 17", 17, pp.509~515 (1996)
- "Interaction of thyroid hormone and steroidogenic acuteregulatory protein in the regulation of murine Ley-dig cell steroidogenesis. J Steroid Biochem Mol Biol 76" (2001)
- "T-3 directlystimulates basal and modulates LH induced testosteroneand estradiol production by rat Leydig cells in vitro. End-ocr J 47", 47, pp.417~428 (2000)
- "Peroxisomes and intracellularcholesterol trafficking in adult rat Leydig cells followingluteinizing hormone stimulation. Tissue Cell 32", 32, pp.102~106 (2000)
- "Signs of aging areapparent in the testis interstitium of Sprague Dawley rats at6 months of age. Tissue Cell 27", 27, pp.689~699 (1995)
- "Effects of chronic luteinizing hormone treatment onLeydig cell structure and function in adult rats. Tissue Cell30", 30, pp.64~73 (1998)
- "Differentiation of adult Leydigcells in the neonatal rat testis is arrested by hypothyroi-dism. Biol Reprod 59", 59, pp.351~357 (1998)
- "Sources of error inthe estimation of Leydig cell numbers in control and atro-phied mammalian testes. J Microsc 159", pp.73~82 (1990)
- "Experimentalcryptorchidism in the mouse II. A hormonal study. J And-rol 11", pp.548~554 (1990)
- "Com-parison of components of the testis interstitium with testo-sterone secretion in hamster rat and guinea pig testes per-fused in vitro. Am J Anat 181", pp.12~22 (1988)
- "Clinical practice guidelines for screening and monitoringmale patients receiving testosterone supplementation thera-py. Int J Impotence Res 8", 8, pp.95~97 (1996)
- "Morphometric analysis of Leydigcells in the normal rat testis. J Cell Biol 84", pp.340~354 (1980)
- "Stereologicalanalysis of Leydig cell ultrastructure in aged humans. JClin Endocrinol Metab 55", pp.634~641 (1982)
- "Thyroid hormone. In: Norman AW, Lit- wack GL (eds.),", pp.169~191 (1997), Acade-mic Press
- "Induction of insulin resistance by androgen and estro-gens. J Clin Endocrinol Metab 79", pp.275~281 (1994)
- "Influence of sex horm-ones on plasma endothelin levels. Ann Intern Med 118", pp.429~432 (1993)
- "Effects of aging on LH and prolactinafter LHRH methyldopa and stress in the malerat. Proc Soc Exp Biol Med 151", pp.507~511 (1976)
- "Aging effects on the hypothalamichypophyseal-gonadal control system in the rat. In", pp.159~192 (1978), RavenPress
- "Structural Changes in rat Leydig cells posthypophy-sectomy", pp.498~508 (1992)
- "Acute Regulation of Leydig cell steroido-genesis-In", pp.241~257 (1996), Cache River Press
- "The unbiased estimation of number and sizes ofarbitrary particles using the disector. J Microsc", pp.127~137 (1984)
- "Thedevelopment of the adult type Leydig cell population in therat testis is affected by neonatal thyroid hormone levels.Biol Reprod 59", 59, pp.344~350 (1998)
- "Leydig cell function in old age. In", pp.458~463 (1976)
- "a model for the human. Endo-crinology 133", pp.2773~2781 (1993)
- "Testicular steroidogenesis in the aging Brown Norway rat.J Androl 14", pp.118~123 (1993)
- "349─ Effects of Luteinizing and Thyroid Hormones on the Aged Leydig Cells ─"
