Prenatal methylazoxymethanol exposure alters evoked responses in fetal rats.
Although there is considerable interest in identifying methods to detect central nervous system impairment early in development, few behavioral assessment tools are available for detecting CNS deficits in the fetus. In the present study, methylazoxymethanol [MAM; Midwest Research Institute, (MRI)] was used to induce deficits in CNS development in fetal rats to assess effects on coordinated fetal behavior. Fetuses were exposed by administering MAM to pregnant rats on E17 of gestation via intraperitoneal injection and then were prepared for behavioral testing 3 days later on E20. After externalization from the uterus into a warm saline bath, fetal subjects received either an intraoral infusion of lemon extract to evoke a facial wiping response or were presented with an artificial nipple to evoke an oral grasping response. Interlimb coordination and paw-face contact during facial wiping were disrupted in MAM-exposed fetuses. Similarly, MAM exposure diminished the ability of fetuses to grasp or maintain oral contact with the artificial nipple. Although clear disruptions of movement coordination were seen in the MAM-treated subjects, there were no significant differences from saline controls in weight or anatomical measures. Together, these findings suggest that behavioral assessments of fetal motor coordination may be useful in identifying neural insult during prenatal development.
Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, IA 52242, USA. gale-kleven@uiowa.edu
Gale A
GA
Kleven
Laila
L
Queral
Scott R
SR
Robinson
D000704:Analysis of Variance; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D002493:Central Nervous System Diseases / Q000139:chemically induced*; D004305:Dose-Response Relationship, Drug; D004622:Embryo, Mammalian / Q000187:drug effects / Q000503:physiopathology; D005145:Face / Q000502:physiology; D005260:Female; D007274:Injections, Intraperitoneal; D008297:Male; D008746:Methylazoxymethanol Acetate / Q000031:analogs & derivatives* / Q000633:toxicity*; D009055:Mouth / Q000187:drug effects / Q000502:physiology; D009068:Movement / Q000187:drug effects*; D010812:Physical Stimulation; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects; D013723:Teratogens / Q000633:toxicity*
D013723:Teratogens; D008746:Methylazoxymethanol Acetate; C030667:methylazoxymethanol