Postnatal changes in the distribution of acetylcholinesterase in kitten striate cortex

Abstract

We have traced the postnatal development of axons and cells in kitten striate cortex that contain acetylcholinesterase (AChE) by using a modification of Koelle's histochemical method. The maturation of AChE-positive axons was not found to be fully complete until at least 3 months of age, and was characterized by several distinct developmental trends. AChE-positive fibers in layers IVc-VI proliferate rapidly after birth until, by 4 weeks postnatal, they appear to exceed the adult density. They remain at this level as late as 8 weeks and then decrease to the adult density by 13 weeks. In contrast, the AChE-positive fibers in layer I do not show a substantial increase in density until 6 weeks of age and the adult level is not achieved before 3 months postnatal. Finally, the density of AChE-positive fibers in layers II and III appears to increase gradually from birth until the mature pattern is reached at about 6 weeks. AChE could also be localized histochemically to cell bodies whose position and appearance depended on postnatal age. Stained cells first appeared in the white matter subjacent to layer VI shortly after birth. By 2 weeks of age, most cells in layer VI were also AChE positive. The staining of these cells gradually disappears over the next 2 months until, at 3 months of age, there are no AChE-positive cells in cat striate cortex. However, a subpopulation of stained neurons appears in layer V by 1 year of age that persists throughout adulthood. The possible contributions of acetylcholine and AChE to the postnatal development of kitten striate cortex are discussed.

Development and Differentiation of the Anuran Auditory Brainstem during Metamorphosis: An Acetylcholinesterase Histochemical Study

“…In the aquatic frog Xenopus, the appearance of AChE activity coincides temporally with the initial formation of tectoisthmotectal projections [Udin and Fisher, 1985]. These observations support the proposal that AChE may serve as a histochemical marker for periods of synaptogenesis [Bear et al, 1985;Robertson et al, 1991], synapse stabilization, and dendritic elaboration [Barone et al, 1994]. The significant amounts of rearrangement occurring in anuran nervous systems during metamorphosis imply changes in nuclear cytoarchitecture and maturation and stabilization of new synapses during this developmental period.…”

“…The isozyme BuChE and AChE are sequentially expressed in proliferating and differentiating neurons, respectively [Layer, 1983;Willbold and Layer, 1994]. In addition, AChE is transiently expressed in mammalian cortex, midbrain and cerebellum during prenatal and early postnatal development [Kostovic and Rakic, 1984;Bear et al, 1985;Robertson et al, 1991;Barone et 112 Brain Behav Evol 1998;52:111-125 Kumaresan/Kang/Simmons Illing and Graybiel, 1994], but staining intensity in some brain areas declines or disappears after a period of maturation. In the aquatic frog Xenopus, the appearance of AChE activity coincides temporally with the initial formation of tectoisthmotectal projections [Udin and Fisher, 1985].…”

The Cholinergic System in Developing Cerebellum: Comparative Study of Normal, Hypothyroid and Underfed Rats

“…It should be mentioned that the period of Purkinje cell formation [25] occurred before the beginning of the athyroidal state, but after that of undernutrition. Finally, although no direct evidence is yet available to indicate whether ChAT-positive Purkinje cells synthesize Ach, we can pro pose the hypothesis of an involvement of Ach in the early development of cerebellar Pur kinje cells as a trophic element rather than neurotransmitter, as previously suggested elsewhere, especially in the autonomic ner vous system [10,39,53,69]. Current studies on Purkinje cells isolated in bulk from nor-mal and abnormal neonates using a method developed in our group [68] may support this concept.…”

Regulation of Acetylcholinesterase Expression during Neuronal Differentiation

“…Certain neurons and muscle and hematopoietic cells express AChE, although each cell type is derived from a distinct developmental lineage. AChE may also be expressed only transiently by certain cells during development (Bear et al, 1985;Robertson et al, 1985). Permanent activation of the Ache gene and regulation of expression through mRNA stabilization may function to ensure rapid availability of the enzyme at any time during differentiation.…”