Involvement of polyamines in the progestin-induced stimulation of endometrial glycogen synthesis during organ culture

Addition of progesterone to an organ culture of endometrial fragments increased glycogen levels 2-3 fold. Concomitant with this increase in glycogen was an increase in S-adenosyl-L-methionine decarboxylase activity and the conversion of putrescine into spermidine. When an inhibitor of S-adenosyl-L-methionine decarboxylase, methylglyoxyl bis(guanylhydrazone), was added to the culture with progesterone, glycogen synthesis was blocked. Inhibition of glycogen synthesis was reversed by the addition of spermidine, suggesting that spermidine synthesis may be necessary for the progestin-induced accumulation of endometrial glycogen.