OBJECTIVE: To determine estrogen plasmatic levels and clinical effects after oral and transdermal estrogen administration to postmenopausal women. MATERIAL AND METHODS: Prospective, longitudinal, deliberate intervention, sequential, crossed and simpleblinded study. Group 1 (n=22) consisted of two cycles of oral treatment and two cycles of transdermal. Group 2 (n=25), inverse sequence. Three estradiol measurements: basal, at 8 and 16 weeks. RESULTS: The estradiol (E2) plasmatic levels were greater in the oral therapy than in the transdermal; in both cases E2 did not return to basal levels after 7 days of treatment conclusion; the clinical improvement is independent of estrogen administration. CONCLUSION: Better levels are achieved with natural conjugated estrogens than with 17betaestradiol. The period without treatment after each cycle must be rol than 7 days.

Estrogen therapy is increasing and this requires an adequate knowledge of the mechanism of action of steroids, being known when transport and metabolism. Therefore we discuss the molecular aspects of estrogen action at the level of nuclear receptors, specifying the structure and operation thereof. Transcription factors is reviewed, describing their DNA binding domains and activation. Transcription accuracies, the paper polymerase II and general transcription factors, forming the transcription initiation complex. Culminates exposing how the regulation of receptor concentration through the mechanism of filling and pointing out some clinical implications. Estrogen therapy is increasing and is appropriate for use is the result of a proper understanding of the mechanism of action of estrogen in the target cell; This knowledge allows us to understand biomolecular individual or group response t...

Estrogen therapy is increasing and this requires an adequate knowledge of the mechanism of action of steroids, being known when transport and metabolism. Therefore we discuss the molecular aspects of estrogen action at the level of nuclear receptors, specifying the structure and operation thereof. Transcription factors is reviewed, describing their DNA binding domains and activation. Transcription accuracies, the paper polymerase II and general transcription factors, forming the transcription initiation complex. Culminates exposing how the regulation of receptor concentration through the mechanism of filling and pointing out some clinical implications. Estrogen therapy is increasing and is appropriate for use is the result of a proper understanding of the mechanism of action of estrogen in the target cell; This knowledge allows us to understand biomolecular individual or group response t...

OBJECTIVE: To determine estrogen plasmatic levels and clinical effects after oral and transdermal estrogen administration to postmenopausal women. MATERIAL AND METHODS: Prospective, longitudinal, deliberate intervention, sequential, crossed and simpleblinded study. Group 1 (n=22) consisted of two cycles of oral treatment and two cycles of transdermal. Group 2 (n=25), inverse sequence. Three estradiol measurements: basal, at 8 and 16 weeks. RESULTS: The estradiol (E2) plasmatic levels were greater in the oral therapy than in the transdermal; in both cases E2 did not return to basal levels after 7 days of treatment conclusion; the clinical improvement is independent of estrogen administration. CONCLUSION: Better levels are achieved with natural conjugated estrogens than with 17betaestradiol. The period without treatment after each cycle must be rol than 7 days.