Biomaterial Database

Retinal projections in larval, transforming and adult sea lamprey, Petromyzon marinus. 1977

M C Kennedy, and K Rubinson

Unilateral enucleations were performed on larval, transforming and adult sea lampreys. Following 5 to 11 days survival, the animals were sacrificed and the brains were processed using a modified Fink-Heimer technique. In larvae, contralateral optic projections were found to the posterior one-third of the dorsal thalamus, the pretectum, and the optic tectum. No ipsilateral projections were present in the larvae. In enucleated transforming and adult lampreys, degenerating axons were observed in the optic chiasm and bilaterally in the optic tracts. Retinal efferents projected bilaterally to a lateral neuropil region ("tractus opticus") in the posterior one-half of the dorsal thalamus. Contralaterally, a conspicuous dorsomedial cell group (lateral geniculate nucleus) also received a projection. Contralateral projections to the superficial layers of the pretectum and optic tectum were observed. Ipsilateral retinal projections to the pretectum and optic tectum in transforming and adult lampreys were restricted to a small zone at the ventrolateral margins of the pretectum and tectum. The changes in distribution of retinofugal projections during transformation appear to be occurring at the same time that the eye differentiates into its adult form.

UI	MeSH Term	Description	Entries
D007798	Lampreys	Common name for the only family (Petromyzontidae) of eellike fish in the order Petromyzontiformes. They are jawless but have a sucking mouth with horny teeth.	Eels, Lamprey,Petromyzontidae,Petromyzontiformes,Eel, Lamprey,Lamprey,Lamprey Eel,Lamprey Eels
D007814	Larva	Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.	Maggots,Tadpoles,Larvae,Maggot,Tadpole
D008636	Mesencephalon	The middle of the three primitive cerebral vesicles of the embryonic brain. Without further subdivision, midbrain develops into a short, constricted portion connecting the PONS and the DIENCEPHALON. Midbrain contains two major parts, the dorsal TECTUM MESENCEPHALI and the ventral TEGMENTUM MESENCEPHALI, housing components of auditory, visual, and other sensorimoter systems.	Midbrain,Mesencephalons,Midbrains
D008675	Metamorphosis, Biological	Profound physical changes during maturation of living organisms from the immature forms to the adult forms, such as from TADPOLES to frogs; caterpillars to BUTTERFLIES.	Biological Metamorphosis,Biological Metamorphoses,Metamorphoses, Biological
D012160	Retina	The ten-layered nervous tissue membrane of the eye. It is continuous with the OPTIC NERVE and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the CHOROID and the inner surface with the VITREOUS BODY. The outer-most layer is pigmented, whereas the inner nine layers are transparent.	Ora Serrata
D001931	Brain Mapping	Imaging techniques used to colocalize sites of brain functions or physiological activity with brain structures.	Brain Electrical Activity Mapping,Functional Cerebral Localization,Topographic Brain Mapping,Brain Mapping, Topographic,Functional Cerebral Localizations,Mapping, Brain,Mapping, Topographic Brain
D005399	Fishes	A group of cold-blooded, aquatic vertebrates having gills, fins, a cartilaginous or bony endoskeleton, and elongated bodies covered with scales.
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D013477	Superior Colliculi	The anterior pair of the quadrigeminal bodies which coordinate the general behavioral orienting responses to visual stimuli, such as whole-body turning, and reaching.	Colliculus, Superior,Optic Lobe, Human,Optic Lobe, Mammalian,Optic Tectum,Anterior Colliculus,Superior Colliculus,Tectum, Optic,Colliculi, Superior,Colliculus, Anterior,Human Optic Lobe,Human Optic Lobes,Mammalian Optic Lobe,Mammalian Optic Lobes,Optic Lobes, Human,Optic Lobes, Mammalian,Optic Tectums,Tectums, Optic
D013788	Thalamus	Paired bodies containing mostly GRAY MATTER and forming part of the lateral wall of the THIRD VENTRICLE of the brain.	Thalamencephalon,Thalamencephalons