Effects of oral contraceptives containing different progestogens on sodium-lithium countertransport in normal females

Abstract

In view of the lack of unanimity on the effect of longterm intake of combined oral contraceptives (OC) on external sodium-dependent lithium efflux, otherwise known as sodium-lithium countertransport (SLC), we undertook a double-blind study to investigate the possible interaction between SLC and OC in healthy women with regular menstrual cycles.In a group of 17 volunteers, aged 27.0 ± 1.1 years (mean ± s.e.m.) and weighing 61.4 ± 2.0 kg, ingestion of 30 g ethinyloestradiol + 150 g desogestrel for 3 months caused an increase in SLC activity from a baseline value of 0.254 ± 0.017 mmol/lcell.h to 0.274 ± 0.017 mmol/lcell.h (P = 0.05). The activity of the transport system after 6 months treatment remained higher than at baseline (0.280 ± 0.016 mmol/lcell.h, P Ͻ 0.025) but was comparable to that at 3 months.

Role of Counterion in the Adsorption Behavior of 1:1 Ionic Surfactants at Fluid Interfaces—Adsorption Properties of Alkali Perfluoro-n-octanoates at the Air/Water Interface

“…Differences in the efficacy of the monovalent hydrated alkali cations Li + , Na + , and K + have often been observed in various fields of application reaching from inorganic clay swelling, molecular ion recognition, , plant growth, or human physiology such as cardiac cell membrane, enzyme activity, contraceptives, and pharmacology. , The therapeutic effect of lithium has now generally been accepted for the treatment of manic depressive psychosis since the 1950s …”

Lithium: a potential estrogen signaling modulator

“…Lithium permeates cells through sodium-potassium ATPase pumps and this permeation is dependent on sodium-lithium counterflow and exchange (Pandey et al 1978), which increases cytoplasmic pH levels thus altering cell activity (Kobayashi et al 2000). Sodium-lithium counterflow is increased by long-term use of oral contraceptives (Adebayo et al 1998); interestingly, lithium does not alter ERα expression in murine uterine tissue, but ovariectomized mice treated with combined estrogen and lithium show reduced uterine ERα expression (Gunin et al 2004).…”