| First Author | Martin P | Year | 1994 |
| Journal | Brain Res Dev Brain Res | Volume | 77 |
| Issue | 2 | Pages | 215-25 |
| PubMed ID | 8174230 | Mgi Jnum | J:16943 |
| Mgi Id | MGI:65000 | Doi | 10.1016/0165-3806(94)90198-8 |
| Citation | Martin P, et al. (1994) Heterotypic sprouting of serotonergic forebrain fibers in the brindled mottled mutant mouse. Brain Res Dev Brain Res 77(2):215-25 |
| abstractText | The brindled mottled mouse has a mutation on the X-chromosome which causes alterations in copper metabolism. One role for copper is as a cofactor for dopamine-beta-hydroxylase (DBH), the enzyme that converts dopamine to norepinephrine (NE). This may explain the fact that the hemizygous males have low concentrations of NE, as well as high concentrations of 5-hydroxyindoleacetic acid (5-HIAA) in the brainstem and forebrain. The present study quantified serotonin (5-HT) immunoreactive fibers in the cerebral cortex and striatum of hemizygous males and control littermates on postnatal (P) days 7, 10, 12 and 14. The density of 5-HT immunoreactive fibers was measured using a digitized imaging system in conjunction with darkfield microscopy. Measurements of 5-HT innervation showed an age-dependent increase in density of 5-HT immunoreactive fibers in all layers of the cerebral cortex, with fiber density in brindled mice approximately 70% greater than controls by P14. High performance liquid chromatography confirmed the increased concentrations of 5-HT and 5-HIAA, and the low concentration of NE, in several regions. We believe that these results are an example of heterotypic sprouting of 5-HT neurons, similar to that observed in neonatal rats given 6-hydroxydopamine (6-OHDA). If so, these data provide the first description of 5-HT heterotypic sprouting in mice, and the first description of 5-HT heterotypic sprouting resulting from a natural disease state, rather than an experimentally induced lesion. |
