Thomas Eric O, Licht Paul
Department of Integrative Biology, University of California, Berkeley, California 94720.
J Morphol. 1993 Feb;215(2):195-200. doi: 10.1002/jmor.1052150207.
In anuran amphibians, there is increasing evidence that exocrine glands dispersed throughout the general integument are secondary sex characters (SSC). Following the recent discovery of sexually dimorphic "breeding glands" in the dorsum of male Rana pipiens, we studied the effects of castration and testosterone treatment on the dorsal skin glands of male Xenopus laevis and R. pipiens to determine whether the dorsal breeding glands, or any other dorsal skin glands, are androgen dependent. The dorsal skin glands of X. laevis were unaffected by androgen status. By contrast, in R. pipiens, breeding, mucous, and seromucous glands responded to testosterone stimulation. Mucous glands were significantly (P < 0.05) larger in testosterone-treated frogs than in castrates. There was a large, but statistically insignificant, increase in the size of the dorsal breeding glands. Testosterone treatment also increased the epithelial cell height of breeding and seromucous glands (P < 0.05). In the skins of castrated and testosterone-treated frogs, there was a reciprocal relationship between the abundance of seromucous and breeding glands: in castrates, seromucous glands were abundant and breeding glands virtually absent, whereas in testosterone-treated frogs, breeding glands were abundant and seromucous glands less common. The total number of the two gland types was similar in both treatment groups. Glands that appeared to be intermediate in form between seromucous and breeding glands were observed in some frogs. These data suggest that seromucous glands may be the regressed form of breeding glands in the dorsal skin of R. pipiens and that the dorsal skin of R. pipiens is a SSC. © 1993 Wiley-Liss, Inc.
在无尾两栖动物中，越来越多的证据表明，遍布整个体表的外分泌腺是第二性征（SSC）。随着最近在雄性北美豹蛙背部发现有性别差异的“繁殖腺”，我们研究了去势和睾酮处理对雄性非洲爪蟾和北美豹蛙背部皮肤腺的影响，以确定背部繁殖腺或任何其他背部皮肤腺是否依赖雄激素。非洲爪蟾的背部皮肤腺不受雄激素状态的影响。相比之下，在北美豹蛙中，繁殖腺、黏液腺和浆液黏液腺对睾酮刺激有反应。经睾酮处理的青蛙的黏液腺明显（P < 0.05）比去势青蛙的大。背部繁殖腺的大小有较大增加，但在统计学上不显著。睾酮处理还增加了繁殖腺和浆液黏液腺的上皮细胞高度（P < 0.05）。在去势和经睾酮处理的青蛙皮肤中，浆液黏液腺和繁殖腺的丰度呈反比关系：在去势青蛙中，浆液黏液腺丰富而繁殖腺几乎不存在，而在经睾酮处理的青蛙中，繁殖腺丰富而浆液黏液腺较少见。两个处理组中这两种腺的总数相似。在一些青蛙中观察到了形态介于浆液黏液腺和繁殖腺之间的腺。这些数据表明，浆液黏液腺可能是北美豹蛙背部皮肤中繁殖腺的退化形式，并且北美豹蛙的背部皮肤是一种第二性征。© 1993威利 - 利斯公司。
