The distribution of serotonergic nerves in microencephalic rats treated prenatally with methylazoxymethanol.
Prenatal exposure of pregnant rats to methylazoxymethanol acetate (MAM) induces microencephaly in the offspring. In the present study of these microencephalic rats (MAM rats) we used quantitative autoradiography to investigate [3H] paroxetine binding sites, which are a selective marker of serotonin (5-HT) transporters (5-HTT). The binding in the accumbens, cortex, hippocampus, and dorsolateral thalamus was significantly increased in MAM rats, compared to the control rats, while there was a significant decrease in the dorsal raphe nucleus of the MAM rats. The levels of 5-HTT mRNA in the dorsal raphe nuclei were analyzed by in situ hybridization, which revealed a significant decrease in 5-HTT mRNA-positive neurons in the MAM rats compared to the control rats. The results imply serotonergic hyperinnervation in the cerebral hemispheres of MAM rats, while a target-dependent secondary degeneration of 5-HT neurons might be induced in the dorsal raphe nuclei of MAM rats.
Kodama
Y
Y
Department of Psychiatry, National Defense Medical College, Tokorozawa, Saitama, Japan. ykodamas@momo.so-net.ne.jp
Nonaka
R
R
Hagino
Y
Y
Watanabe
M
M
D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism; D002531:Cerebellum / Q000378:metabolism; D002540:Cerebral Cortex / Q000378:metabolism; D005260:Female; D006624:Hippocampus / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism; D026901:Membrane Transport Proteins; D008746:Methylazoxymethanol Acetate / Q000031:analogs & derivatives; D008831:Microcephaly / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D009419:Nerve Tissue Proteins; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D009714:Nucleus Accumbens / Q000378:metabolism; D017374:Paroxetine / Q000378:metabolism; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012333:RNA, Messenger / Q000032:analysis; D011903:Raphe Nuclei / Q000166:cytology / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D050486:Serotonin Plasma Membrane Transport Proteins; D013788:Thalamus / Q000378:metabolism
D002352:Carrier Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D050486:Serotonin Plasma Membrane Transport Proteins; C493232:Slc6a4 protein, rat; D012701:Serotonin; D017374:Paroxetine; D008746:Methylazoxymethanol Acetate; C030667:methylazoxymethanol