Experimental Cell Research I73 (1987) 117-128 Establishment and Characterization of Xenopus Oviduct Ceils in Primary Culture JOAN MARSH and JAMSHED R. TATA’ Laboratory of Developmental Biochemistry, National institute for Medical Research, Mill Hill, London NW7 IAA, United Kingdom Based on a previously established procedure for Xenopus hepatocytes, we describe tubular oviduct cells in primary culture which continue to secrete substantial quantities of egg jelly for several days, as can be visualized microscopically. Freshly isolated cells exhibited a culture shock response [A. P. Wolffe, J. F. Glover, and J. R. Tata (1984) Exp. Cell Res. 154, 5811, from which they recovered by the third day in culture. This recovery was characterized by (a) the diminished synthesis of heat shock proteins hsp 70 and hsp 85, (b) the cessation of the drop in number of estrogen receptor, and (c) the enhanced rate of synthesis of cellular and secreted proteins. The oviduct estrogen receptor had the same characteristics as those in other estrogen target tissues and was present in the same amount as in adult female Xenopus hepatocytes [A. J. Perlman, A. P. Wolffe, J. Champion, and J. R. Tata (1984) Mol. Cell. Endocrinol. 38, 511. Unlike the latter in primary culture [M. P. R. Tenniswood, P. F. Searle, A. P. Wolffe, and J. R. Tata (1983) Mol. Cell. Endocrinol. 30, 3291, oviduct cell cultures did not actively metabolize either estradiol or progesterone (t,a=55 and 7 h, respectively). The successful establishment and characterization of primary cultures of both liver and oviduct cells now fultil the conditions required for investigating the basis for tissue specificity of regulation by estrogen of Xenopus egg protein gene expression in primary cell culture. @ 1987 Academic Press, Inc. In all oviparous vertebrates the synthesis of the major proteins of the egg yolk, particularly the precursor protein vitellogenin, is obligatorily regulated by estro- gen in the liver [ 11. The de nouo activation of the dormant vitellogenin genes by the steroid hormone has been most profitably studied in primary cultures of male Xenopus hepatocytes [2] and has provided a valuable insight into the hormonal regulation of gene expression. As an approach to the investigation of the tissue specificity of hormonal regulation of gene expression, our laboratory initiated studies on the nature and synthesis of the egg coat proteins and the mRNAs encoding them in Xenopus laeuis oviduct in the intact animal [3, 41. Unlike the liver, where egg protein synthesis is regulated only by estrogen, that in the oviduct of oviparous vertebrates is under the control of both estrogen and progesterone. In order to define more precisely the role of these hormones and their receptors in the early stages of hormone action, it was necessary to establish a primary cell culture system for Xenopus oviduct cells, based on the method developed for Xenopus hepatocytes [21. The major requirement for optimizing Xenopus oviduct cells in primary culture was to ensure the viability of the cells for sufftciently long periods such that they retained in culture hormonal responses similar to those found in uiuo. The ’ To whom reprint requests should be addressed. 117 Copyright 0 1987 by Academic Press. Inc. All rights of reproduction in any form reserved 0014-4827/87 103.00