Effects of 17 alpha-ethinyl oestradiol in vitro on erythrocyte cation transport in men and women.
The effects of 17 alpha-ethinyl oestradiol in vitro upon erythrocyte Na(+)-K+ cotransport were investigated in nine normal males and in eight normal females during the mid-follicular phase of the menstrual cycle. At a concentration of 10(-1) mmol/l, Na(+)-K+ cotransport was almost completely inhibited. At concentrations of 10(-12) to 10(-2) mmol/l, a minor concentration-related effect was observed in males but not females. In the same concentration range, there was a significant difference in Na(+)-K+ cotransport between sexes. Thus, erythrocyte Na+K+ cotransport is lower in females than males, probably due to chronic exposure of their erythrocytes to endogenous oestrogen.
Monaghan
J C
JC
Department of Clinical Pharmacology, Royal North Shore Hospital, St Leonards, N.S.W. Australia.
Flemming
C L
CL
Stokes
G S
GS
D000328:Adult; D001692:Biological Transport / Q000187:drug effects; D002352:Carrier Proteins / Q000378:metabolism; D002412:Cations / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000378:metabolism*; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005260:Female; D005498:Follicular Phase; D006801:Humans; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D012727:Sex Characteristics; D012964:Sodium / Q000378:metabolism; D028021:Sodium-Potassium-Chloride Symporters
D002352:Carrier Proteins; D002412:Cations; D028021:Sodium-Potassium-Chloride Symporters; D004997:Ethinyl Estradiol; D012964:Sodium