Generation and death of cells in the dorsal lateral geniculate nucleus and superior colliculus of the wallaby, Setonix brachyurus (quokka).
To study postnatal cell generation in primary visual centres of the quokka, tritiated thymidine was injected into pouch-young aged postnatal day (P)1-P85. Brains were examined at P100, just before eye-opening, when primary visual projections are essentially mature. Neurons in the dorsal lateral geniculate nucleus (dLGN) and superior colliculus (SC) were generated at P1-P10 and P1-P18 respectively. Peak numbers of labelled cells were seen at P3 and P5 in the dLGN and SC. Cell death was assessed in the dLGN and SC of young aged P10-P150. Low numbers of dying cells were seen in the dLGN throughout this period, with a small peak at P85. A more substantial peak of cell death was seen in the SC, also at P85. In the quokka, the time interval between the peaks of cell generation and of cell death in the dLGN and SC is 70-80 days, considerably longer than the interval of 40 days between birth and death of retinal cells.
Harman
A M
AM
Department of Psychology, University of Western Australia, Nedlands.
D000818:Animals; D002452:Cell Count; D002455:Cell Division; D002470:Cell Survival; D005829:Geniculate Bodies / Q000166:cytology*; D007614:Macropodidae / Q000033:anatomy & histology*; D009457:Neuroglia / Q000166:cytology; D009474:Neurons / Q000502:physiology*; D013477:Superior Colliculi / Q000166:cytology*