Estrogen Deprivation During Primate (Papio anubis) Pregnancy: Impact on Systemic Microvascular Flow and Cardiovascular Development and Function After Birth in Offspring.

BACKGROUND

Suppressing estradiol (E2) during baboon pregnancy lowers offspring skeletal muscle capillary density, vital for insulin-mediated glucose uptake, and induces insulin resistance. We examined whether E2 deprivation also impairs microvascular flow and cardiac function.

METHODS

Offspring of untreated baboons, letrozole-treated baboons, or letrozole plus E2 (maternal s.c. injections during the second half of gestation) underwent contrast-enhanced microbubble ultrasonography to quantify microvessel flow and echocardiography to assess cardiac performance.

RESULTS

Letrozole reduced maternal serum E2 by 95% (p < 0.01). In letrozole offspring, microbubble flux rate (β) fell 55% (p < 0.02), replenishment was 5 s slower (p < 0.03), and microvessel flow declined 40% (p = 0.05); all were restored by added E2. Indices of systolic (isovolumic contraction), diastolic (isovolumic relaxation), global performance (Tei index), and cardiac output were unchanged.

CONCLUSION

Prolonged gestational E2 deprivation programs a reduction in microvascular flow without altering cardiac function; maternal E2 prevents this, supporting E2's role in optimizing postnatal perfusion and metabolic health.