Effect of acute ozone exposure on pregnant rat uterus contractile responses.
Pulmonary effects of ozone (O(3)) inhalation have been comprehensively studied, but little is known about its extrapulmonary consequences, particularly in the reproductive tract. Thus, the effects of an acute O(3) exposure on the contractile response of the pregnant rat uterus were evaluated. Nonpregnant and pregnant (5, 10, and 18 days of gestation) rats were exposed to air or O(3) (3 ppm) for1 h, and uterine strips isolated from these animals were studied 16-18 h later. Contractile responses to acetylcholine (ACh) and oxytocin (OT) were evaluated with respect to three parameters (area under the curve, amplitude, and frequency). O(3) did not modify the sensitivity (-logEC(50)) to either agonist at any pregnancy stage, but induced a statistically significant increase in all maximum responses to OT at gestational day 5, and increased the maximum response (area under the curve) to ACh at pregnancy days 5 and 10. Our results suggest that O(3) inhalation can produce abnormal contractility in the pregnant uterus, and identify the need for further investigation of this issue.
Campos-Bedolla
Patricia
P
Unidad de Investigación Médica en Enfermedades Neurológicas, Centro Médico Nacional Siglo XXI, Instituto Mexicano del Seguro Social. Av. Cuauhtémoc 330, CP 06720 México DF, Mexico.
Vargas
Mario H
MH
Montaño
Luis M
LM
D000109:Acetylcholine / Q000494:pharmacology; D000280:Administration, Inhalation; D000818:Animals; D004347:Drug Interactions; D005260:Female; D066298:In Vitro Techniques; D019570:Inhalation Exposure; D010083:Oxidants, Photochemical / Q000633:toxicity*; D010121:Oxytocin / Q000494:pharmacology; D010126:Ozone / Q000008:administration & dosage / Q000633:toxicity*; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D014590:Uterine Contraction / Q000187:drug effects* / Q000502:physiology; D014599:Uterus / Q000187:drug effects* / Q000502:physiology
D010083:Oxidants, Photochemical; D010121:Oxytocin; D010126:Ozone; D000109:Acetylcholine