Surfactant protein A expression is delayed in fetuses of streptozotocin-treated rats.
The content and distribution of the 26-to 38-kDa surfactant protein (SP-A) and its mRNA were determined in fetuses of control and streptozotocin (STZ)-treated Sprague-Dawley rats using immunohistochemistry, RNA blotting, and in situ hybridization. Female rats were treated with 50 mg/kg STZ before mating, and the fetuses were killed at fetal days 18-21 or on neonatal days 1 and 2 (day of birth = end of day 22). SP-A was barely detectable on fetal day 18 in controls and easily detected by fetal day 21. In the STZ group, SP-A was decreased compared with controls at fetal days 18-21. However, by neonatal days 1-2, there were no significant differences in SP-A levels between groups. SP-A mRNA was detectable at fetal day 18 in controls, but it was decreased in the STZ group at day 18-21 (P less than 0.02) and differences were no longer detected by neonatal days 1-2. SP-A and SP-A mRNA accumulated with advancing gestational age in both groups until neonatal days 1-2. The differences in SP-A and SP-A mRNA levels in the two groups diminished with advancing age but remained significant at fetal day 21. These data suggest that STZ-induced diabetes interferes with normal expression of SP-A in the developing fetal lung.
Guttentag
S H
SH
Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02115.
Phelps
D S
DS
Stenzel
W
W
Warshaw
J B
JB
Floros
J
J
D000818:Animals; D000831:Animals, Newborn; D005260:Female; D005333:Fetus / Q000378:metabolism*; D006023:Glycoproteins / Q000378:metabolism; D006943:Hyperglycemia / Q000139:chemically induced / Q000378:metabolism; D008168:Lung / Q000254:growth & development / Q000378:metabolism; D011247:Pregnancy; D011510:Proteolipids / Q000235:genetics / Q000378:metabolism*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013311:Streptozocin / Q000494:pharmacology*; D013997:Time Factors; D014018:Tissue Distribution
D006023:Glycoproteins; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D012333:RNA, Messenger; D013311:Streptozocin