Local application of platelet-activating factor induces cervical ripening accompanied by infiltration of polymorphonuclear leukocytes in rats

• Published in: American journal of obstetrics and gynecology Vol. 187; no. 4; pp. 829 - 833
• Main Authors: Maul, Holger, Shi, Leili, Marx, Stephen G., Garfield, Robert E., Saade, George R.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Philadelphia, PA Mosby, Inc 01.10.2002; Elsevier
• Subjects: Administration, Topical; Animals; Biological and medical sciences; Cervical Ripening - drug effects; cervimeter; Cervix; Cervix Uteri - cytology; Cervix Uteri - drug effects; Cervix Uteri - physiology; collascope; Diseases of mother, fetus and pregnancy; Dose-Response Relationship, Drug; Female; Fluorescence; Gynecology. Andrology. Obstetrics; light-induced fluorescence; Medical sciences; Neutrophil Infiltration - drug effects; parturition; Platelet Activating Factor - administration & dosage; Platelet Activating Factor - pharmacology; Pregnancy; Pregnancy. Fetus. Placenta; Rats; Rats, Sprague-Dawley; Reference Values; collascope; Cervix; light-induced fluorescence; parturition; cervimeter; Pregnancy disorders; Rat; Pathogenesis; Rodentia; Granulocyte; Premature delivery; Fluorescence; Uterine cervix; Platelet activating factor; Ripening; Pathology; Local administration; Vertebrata; Experimental disease; Mammalia; Animal; Female; Threatened premature delivery; Tension
• ISSN: 0002-9378; 1097-6868
• DOI: 10.1067/mob.2002.126983

Objective: The purpose of this study was to determine the effect of locally applied platelet-activating factor on cervical ripening and leukocyte infiltration. Study Design: Timed-pregnant rats were treated vaginally twice each day on days 14 and 15 of gestation with platelet-activating factor 5 × 10−8 mol/L (low-dose), 5 × 10−7 mol/L (high-dose), or solvent and were killed on day 16. Cervical ripening was assessed by cervical resistance-to-stretch and light-induced autofluorescence of cross-linked collagen. Longitudinal sections of the cervix were hematoxylin and eosin stained, and the number of polymorphonuclear leukocytes in eight high-power fields was determined. Results: Cervical resistance-to-stretch and light-induced autofluorescence were decreased in rats that were treated with high-dose platelet-activating factor compared with controls (0.4375 ± 0.0126 N/mm vs 0.5528 ± 0.0294 N/mm, and 2.739 ± 0.150 N/mm vs 3.475 ± 0.236 N/mm; P <.05). High-dose platelet-activating factor led to infiltration with polymorphonuclear leukocytes compared with control (22.1 ± 5.2 vs 2.1 ± 1.3 cells/8 high-power fields, P <.05). Conclusion: Local platelet-activating factor application induces cervical ripening accompanied by stromal polymorphonuclear leukocyte infiltration. Platelet-activating factor may play a major role in parturition under physiologic and pathologic conditions. (Am J Obstet Gynecol 2002;187:829-33.)