Keel B A, Grotjan H E
Biol Reprod. 1985 Feb;32(1):83-9. doi: 10.1095/biolreprod32.1.83.
Chromatofocusing was used to characterize the isohormones of rat luteinizing hormone (rLH) in extracts of pituitaries from intact and bilaterally cryptorchid animals. Pituitary extracts contained at least seven isoelectric variants (isohormones) or rLH: one eluted in the column void volume (Isohormone, I, pI greater than 9.8), five exhibited apparent pI's in the range of 9.25 to 8.97 (designated as Isohormones II-VI) and one bound to the column but eluted with 1.0 M NaCl (Isohormone VII, pI less than 7.0). In both intact and cryptorchid rats, a large percentage of the rLH was present as Isohormone I. Furthermore, Isohormone I was present in greater absolute and relative amounts in cryptorchid rats. All seven rLH isohormones exhibited activity in an in vitro bioassay and the biological to immunological assay (B:I) ratios decreased with their apparent pI's but were not significantly affected by cryptorchidism. When the data were expressed as the product of the amount of rLH and the B:I ratio (termed Bio-Index), Isohormone I was the predominant form of rLH in both cryptorchid and intact rats, with the Bio-Index of Isohormone I being significantly greater for cryptorchid rats. These results suggest that cryptorchidism alters the pattern of rLH isohormones in the pituitary, yielding a greater percentage of the most basic rLH isohormone, which also has the highest B:I ratio. Thus, cryptorchidism significantly alters the qualitative pattern as well as the quantity of rLH in the pituitary.
采用层析聚焦法对正常和双侧隐睾动物垂体提取物中的大鼠促黄体生成素（rLH）同工激素进行了表征。垂体提取物中至少含有七种等电变体（同工激素）或rLH：一种在柱空体积中洗脱（同工激素I，pI大于9.8），五种表观pI在9.25至8.97范围内（命名为同工激素II - VI），一种与柱结合但用1.0 M NaCl洗脱（同工激素VII，pI小于7.0）。在正常和隐睾大鼠中，大部分rLH以同工激素I的形式存在。此外，同工激素I在隐睾大鼠中的绝对量和相对量都更高。所有七种rLH同工激素在体外生物测定中均表现出活性，生物活性与免疫活性测定（B:I）比值随其表观pI降低，但不受隐睾症的显著影响。当数据表示为rLH量与B:I比值的乘积（称为生物指数）时，同工激素I是隐睾和正常大鼠中rLH的主要形式，隐睾大鼠中同工激素I的生物指数显著更高。这些结果表明，隐睾症改变了垂体中rLH同工激素的模式，产生了更高比例的最碱性rLH同工激素，其B:I比值也最高。因此，隐睾症显著改变了垂体中rLH的定性模式和数量。
