The effect of transdermal 17-beta-estradiol on glucose metabolism of postmenopausal women is evident during the oral but not the intravenous glucose administration.
OBJECTIVE
To evaluate the effect of transdermal 17-beta-estradiol (50 micrograms/day) on glucose metabolism of postmenopausal women.


METHODS
A frequently sampled intravenous glucose tolerance test (FSIGT), to calculate insulin sensitivity (SI) and peripheral glucose utilization independent of insulin (SG), and an oral glucose tolerance test (75 g; OGTT), were performed in nine postmenopausal women prior to, and after 2 months of, treatment.


RESULTS
Estradiol decreased insulin and increased the C-peptide/insulin ratio both during fasting (P < 0.02) and OGTT (insulin levels, P < 0.01; C-peptide/insulin ratio, P < 0.05), but not FSIGT. Glucose levels, C-peptide levels, SI and SG were not affected.


CONCLUSIONS
In spite of unmodified SI, the reduction of insulin levels and the increase of the C-peptide/insulin ratio, observed during fasting and OGTT, support a beneficial effect of estradiol on glucose metabolism. This effect probably requires the interplay of estradiol with gastrointestinal factors.
Cagnacci
A
A
Istituto di Fisiopatologia della Riproduzione Umana, University of Modena, Italy.
Tuveri
F
F
Cirillo
R
R
Setteneri
A M
AM
Melis
G B
GB
Volpe
A
A
D000279:Administration, Cutaneous; D000284:Administration, Oral; D001786:Blood Glucose / Q000032:analysis / Q000187:drug effects* / Q000378:metabolism; D002096:C-Peptide / Q000097:blood / Q000187:drug effects / Q000378:metabolism; D004958:Estradiol / Q000008:administration & dosage / Q000494:pharmacology*; D005215:Fasting; D005260:Female; D005947:Glucose / Q000008:administration & dosage; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D007275:Injections, Intravenous; D007328:Insulin / Q000097:blood / Q000378:metabolism*; D008875:Middle Aged; D017698:Postmenopause / Q000187:drug effects* / Q000378:metabolism
D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin; D004958:Estradiol; D005947:Glucose