Estrogen modulates the dimensions of the lung's gas-exchange
surface area and alveoli in female rats.
Massaro, Gloria D., Jacopo P. Mortola, Donald Massaro.
Lung Biology Laboratory and Departments of Pediatrics and Medicine,
Georgetown University School of Medicine, Washington, D.C. 20007,
U.S.A.. Department of Physiology, McGill University, Montreal, Canada
H3G116
APStracts 2:0144L, 1995.
Sexually mature virgin female rats and mice have a higher mass
-specific gas-exchange surface area (Sa) and smaller alveoli than same
aged males even though mass-specific oxygen consumption (VO2) is the
same, within species, in both sexes (Proc. Natl. Acad. Sci. USA
92:1105-1107, 1995). We now report that rats subjected to ovariectomy
at age 21 days had, at age 59 days, a smaller mass-specific Sa and
larger alveoli than sham-ovariectomy rats; these differences were not
due to differences in VO2 and were prevented by estrogen therapy.
Furthermore, sham-ovariectomy rats treated with estrogen had smaller
and more alveoli than sham-operated females not given estrogen.
Androgenization of newborn female rats did not alter mass-specific Sa
or alveolar size. Male mice genetically deficient in androgen
receptors had the same mass-specific Sa as normal male littermates.
We conclude estrogen is responsible for the sexual dimorphism of the
lung's gas-exchange region and induces the formation of smaller more
numerous alveoli in otherwise untreated female rats.
Received 5 July 1995; accepted in final form 15 August 1995.
APS Manuscript Number L207-5.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 24 August 1995.