Stem villous arteries from the placentas of heavy smokers: functional and mechanical properties.
OBJECTIVE
The aim of the study was to compare the mechanical and functional properties of isolated small stem villous arteries from the placentas of women who smoked heavily (>/=15 cigarettes/d) during pregnancy with those from the placentas of nonsmokers.


METHODS
Isolated stem villous arteries were mounted in small-vessel myographs. Circumference-tension relationships were established with 124 mmol/L potassium chloride. Concentration-response curves were obtained for endothelin 1, prostaglandin F2alpha, vasoactive intestinal peptide, corticotropin-releasing hormone, sodium nitroprusside, and cadmium chloride. The effect of nitric oxide was examined with N omega-nitro-l -arginine.


RESULTS
Stem villous arteries from the heavy smoking group developed a significantly lower tension than did those from nonsmokers at 6 of 9 steps of the circumference-tension experiment (P <.05). Endothelin 1 evoked a significantly greater maximum vasoconstrictive response in stem villous arteries from heavy smokers than in those from nonsmokers (P <.05).


CONCLUSIONS
Stem villous arteries of heavy smokers have altered mechanical properties and a greater vasoconstrictive response to endothelin 1 than do those from nonsmokers. These changes may compromise fetal placental blood flow and thereby contribute to the lower birth weights seen among infants born to heavy smokers.
Clausen
H V
HV
Department of Obstetrics and Gynecology, Hvidovre University Hospital, and the Department of Obstetrics and Gynecology, Holbaek County Hospital, Denmark.
Jorgensen
J C
JC
Ottesen
B
B
D001158:Arteries / Q000033:anatomy & histology / Q000502:physiology*; D001696:Biomechanical Phenomena; D019256:Cadmium Chloride / Q000494:pharmacology; D003346:Corticotropin-Releasing Hormone / Q000494:pharmacology; D015237:Dinoprost / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D019332:Endothelin-1 / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D009599:Nitroprusside / Q000494:pharmacology; D010920:Placenta / Q000098:blood supply*; D011189:Potassium Chloride / Q000494:pharmacology; D011247:Pregnancy; D012907:Smoking / Q000009:adverse effects*; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects