Involvement of microtubules in the effect of estradiol on progesterone secretion by hamster corpus lutem

Abstract

Involvement of microtubules in progesterone secretion by the corpus luteum is suggested by experiments wherein the inhibitors of microtubule function such as colchicine and vinblastine inhibited  progesterone ,  secretion. Lumicolchicine, an inactive isomer of colchicine, was found ineffective,  suggesting the specificity of the colchicine effect. The inability of coichicine to affect progesterone  secretion by the carpora lutea pretreated with either D2O or tubulin antibody lends further support  to the suggestion of the requirement of the integrity of microtubules  for  progesterone secretion. Pre-  incubation of corpora lutea either with D2O or tubulin antibody also abolished the inhibitory effect  of estradiol on progesterone secretion, suggesting a role of microtubules in estradiol action.