Georgiou M, Payne A H
Department of Biological Chemistry, University of Michigan, Ann Arbor 48109.
Biol Reprod. 1987 Sep;37(2):335-41. doi: 10.1095/biolreprod37.2.335.
The physical and functional properties of Leydig cell populations obtained by centrifugation of testicular cells in two different density gradient media, Percoll and Metrizamide, were compared. Percoll-gradient centrifugation yielded two Leydig cell bands (Peak I and Peak II) that were comparable, as to their density and testosterone-producing capacity, to the respective Leydig cell bands, Population I and Population II, isolated in a Metrizamide gradient. The denser Leydig cell band (II) had a greater capacity for testosterone production than the less dense band (I), regardless of the type of gradient used for its isolation. Metrizamide gradient centrifugation separated the majority of germ cells from the "light" (Population I) Leydig cells, whereas in the Percoll gradient, germ cells comigrated with Peak I Leydig cells. Leydig cell separation by Percoll gradients was highly dependent on the presence of Ca2+ and Mg2+ in the medium, while these cations had no effect on the separation of Leydig cells by Metrizamide. In conclusion, Metrizamide gradient centrifugation yielded two Leydig cell populations of similar functional and physical properties to the respective populations isolated in Percoll gradients.
比较了通过在两种不同密度梯度介质（Percoll和Metrizamide）中对睾丸细胞进行离心获得的睾丸间质细胞群体的物理和功能特性。Percoll梯度离心产生了两条睾丸间质细胞带（峰I和峰II），就其密度和产生睾酮的能力而言，它们与在Metrizamide梯度中分离出的相应睾丸间质细胞带（群体I和群体II）相当。无论用于分离的梯度类型如何，密度较大的睾丸间质细胞带（II）产生睾酮的能力都比密度较小的带（I）更强。Metrizamide梯度离心将大多数生殖细胞与“轻”（群体I）睾丸间质细胞分离，而在Percoll梯度中，生殖细胞与峰I睾丸间质细胞共同迁移。通过Percoll梯度分离睾丸间质细胞高度依赖于培养基中Ca2+和Mg2+的存在，而这些阳离子对通过Metrizamide分离睾丸间质细胞没有影响。总之，Metrizamide梯度离心产生了两个睾丸间质细胞群体，其功能和物理特性与在Percoll梯度中分离出的相应群体相似。
