Effect of aging on Leydig cells of Sprague Dawley rats |
In-Shik Kim1, Hun-Jin Tae2, Li-Guang Li2, Young-Jae Park2, Hyung-Sub Kang1, Sang-Youel Park1, Soo-Hyun Park1, Young-Seok Park3, Young-Hoon Lee4, Dong-Choon Ahn5, Eun-Young Choi2, Hong-Hyun Yang1 |
1Bio-Safety Research Institute, Chonbuk National University 2Department of Anatomy, College of Veterinary Medicine, Chonbuk National University 3College of Visual Image and Health Kongju National University 4School of Dentistry, Chonbuk National University 5Department of Veterinary Medicine, Kangwon National University |
흰쥐에서 고환 간질세포에 미치는 노화의 영향 |
김인식1, 태현진2, 이여광2, 박영재2, 강형섭1, 박상열1, 박수현1, 박영석3, 이영훈4, 안동춘5, 최은영2, 양홍현1 |
1전북대학교 생체안전성연구소 2전북대학교 수의과대학 해부학교실 3공주대학교 영상보건대학 특수동물학과 4전북대학교 치과대학 해부학교실 5강원대학교 수의학과 |
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Abstract |
The present study investigated the effects of aging on Leydig cells of Sprague Dawley rats. Rats of 3, 6, 12 and 18 months of age were used. Testes of rat were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in epon-araldite. Using $1{mu}m$ sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Testis incubations were used to determine luteinizing hormone (LH; 100 ng/ml) stimulated testosterone secretory capacity per testis in vitro. Testosterone levels in the incubation medium, and testosterone and luteinizing hormone levels in serum of these four groups of rats were determined by radioimmunoassay. Morphological studies revealed that Leydig cells were more abundant in the testis interstitium at 6, 12 and 18 months when compared with 3 months. The volumes of Leydig cells per testis was significantly higher, at 6, 12 and 18 months of age than those at 3 months. The number of Leydig cells per testis was doubled at 6, 12 and 18 months of age compared with 3 months. The average volume of a Leydig cell was not significantly different between 3 and 6 months of age, however, at 12 and 18 months a significantly lower value was observed. LH-stimulated testosterone production per testis in vitro was reduced by 45% at 6 months of age compared with 3 months; a further significant reduction was observed at 12 and 18 months. Serum testosterone and LH levels were not significantly different between 3 and 6 months of age but at 12 and 18 months a significantly lower value was observed in both groups for these hormones. These results showed that signs of aging are apparent in Leydig cells of Sprague Dawley rats at 12 months of age. |
Key Words:
Rat, Aging, Leydig cell |
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