expression of mRNAs coding for other AZF cell proteins, including the transcriptional repressor DAX-1 and the Kv1.4 K+ channel (unpublished observations). However, the range of genes whose expression might be increased or decreased through this novel signaling pathway is yet to be determined. It will be interesting to compare ACTH and cAMP to 8CPT-Ade with respect to their effects on the expression of the entire transcrip- tome of bovine AZF cells. Neither 8CPT-29-OMe-cAMP nor its presumptive metabolites, at concentrations that triggered large increases in cortisol synthesis, increased overall RNA synthesis or AZF cell prolifer- ation. Rather, these agents had a slight inhibitory effect on proliferation. Therefore, none of the delayed increases in cortisol synthesis could be attributed to increases in the number of AZF cells (unpublished observations). 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