Analysis of the morphogenesis and cell proliferation in the retina of a pleuronectiform fish, the turbot Psetta maxima (Pleuronectiformes: Teleostei).

The morphogenesis and cell proliferation in the retina of turbot (Psetta maxima, Pleuronectiformes: Teleostei) from embryo through metamorphosis have been examined by using proliferating cell nuclear antigen (PCNA)-immunohistochemistry and general histological procedures. In the embryonic retina, cell proliferation and spatial cell reorganization form the anlage of the pigment epithelium and neural retina. Neurogenesis begins around hatching in the temporal retina, dorsal to the optic nerve exit, and then a wave of cell differentiation spreads to the nasal retina to yield a laminated retina by the end of the prolarval turbot stage.

The terminal nerve in turbot, Psetta maxima: a developmental immunocytochemical study.

The ontogeny and organization of the terminal nerve (TN) during turbot development was studied using an antiserum to neuropeptide Y. First immunoreactive cells were detected in the olfactory placode at hatching time. At 1 day after hatching, a loose group of labeled neurons form an extracranial primordial ganglion of the TN.

Emergence of axonal tracts in the developing brain of the turbot (Psetta maxima).

In this study we have investigated the pattern of morphogenesis and axogenesis in the turbot brain during embryonic and early larval stages with immunohistochemistry using an antibody against acetylated tubulin. The first immunoreactive elements were detected at 74 h post-fertilization in fibers running in the medial and lateral longitudinal fascicles. Newly positive axonal bundles are progressively added during development forming rostrocaudally directed tracts.

Distribution of GABA-immunolabeling in the early zebrafish (Danio rerio) brain.

The spatial and temporal pattern of GABA-expression in the brains of zebrafish (Danio rerio) embryos was studied by means of immunohistochemical techniques. GABA is said to exert neurotrophic actions in the early regulation of the differentiation of the central nervous system. In early stages GABAergic cells form distinct clusters throughout the CNS.

Immunochemical localization of calretinin in the retina of the turbot (Psetta maxima) during development.

The expression of the calcium-binding protein calretinin was analysed by immunohistochemistry techniques in the retina of turbot (Psetta maxima) from embryonic to juvenile stages. Calretinin immunoreactivity was first detected in retinae from newly hatched larvae, in which the anlage of the inner plexiform layer and a subset of amacrine and ganglion cells displayed a faint immunolabelling. First appearance of photoreceptors during larval life coincided with an increase in the intensity of the labelling.