Evaluating vaginal moisture in mice with calibrated filter paper

Area of Science:

• Reproductive Biology
• Endocrinology
• Gynecology

Background:

• Postmenopausal estrogen loss causes vaginal dryness.
• Depot-medroxyprogesterone acetate (DMPA) contraceptive use also reduces estrogen and can cause vaginal dryness.
• Objective methods are needed to measure vaginal moisture in mouse models of estrogen deficiency.

Purpose of the Study:

• To develop and validate an objective method for measuring vaginal moisture in mice.
• To assess if mouse models of hypoestrogenism (DMPA-treated or ovariectomized) replicate vaginal moisture changes observed in women.

Main Methods:

• Calibrated filter paper strips were used to measure vaginal fluid levels in vivo.
• Mice models included: untreated ovary-intact, DMPA-treated ovary-intact, and ovariectomized (OVX).
• Circulating estradiol levels were measured concurrently.

Main Results:

• Vaginal moisture levels, measured by filter paper, were significantly lower in DMPA-treated and OVX mice compared to estrus-stage mice.
• Estradiol levels were also significantly lower in DMPA-treated and OVX mice.
• Filter paper readings correlated with circulating estradiol levels.

Conclusions:

• Calibrated filter paper provides a reliable and objective measure of vaginal moisture in mice.
• DMPA-treated and OVX mice serve as valid models for studying vaginal moisture loss associated with hypoestrogenism.
• These findings support the use of mouse models to investigate vaginal dryness in women with reduced estrogen levels.