Biomaterial Database

Ultrastructural changes in the nucleoplasm of hamster facial neurons during a postnatal maturation period. 1986

K J Jones, and A LaVelle

Changes in the characteristics of the nucleoplasm were examined in young hamster facial motoneurons of 15 and 20 days postnatal age and in the adult (100 days postnatal age) at both the light and electron microscope levels. In toluidine-blue stained 1-micron thick sections, a progressive increase in basophilic islands within the nucleoplasm occurred during maturation. Ultrastructural changes that were observed during final development included a transition from a homogeneous, 'filled-in' appearing nucleoplasm to a clumped-appearing nucleoplasm. This process principally involved the formation of distinct clusters of interchromatin granules that was associated with a loss of fine fibrils, an increase in clear spaces between intervening fibrillar and granular material, and an increase in small scattered clumps of heterochromatin. These changes in both ribonucleoprotein (RNP)-and DNA-containing nuclear constituents (interchromatin granules and heterochromatin, respectively) occurred during a postnatal maturational period previously demonstrated to involve other alterations in nuclear structures. It is interpreted that these cytomorphic changes in the nucleoplasm reflect an underlying metabolic shift at the transcriptional level during the transition from an actively growing neuron to an adult functioning neuron.

UI	MeSH Term	Description	Entries
D008647	Mesocricetus	A genus in the order Rodentia and family Cricetidae. One species, Mesocricetus auratus or golden hamster is widely used in biomedical research.	Hamsters, Golden,Hamsters, Golden Syrian,Hamsters, Syrian,Mesocricetus auratus,Syrian Golden Hamster,Syrian Hamster,Golden Hamster,Golden Hamster, Syrian,Golden Hamsters,Golden Syrian Hamsters,Hamster, Golden,Hamster, Syrian,Hamster, Syrian Golden,Syrian Hamsters
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009046	Motor Neurons	Neurons which activate MUSCLE CELLS.	Neurons, Motor,Alpha Motorneurons,Motoneurons,Motor Neurons, Alpha,Neurons, Alpha Motor,Alpha Motor Neuron,Alpha Motor Neurons,Alpha Motorneuron,Motoneuron,Motor Neuron,Motor Neuron, Alpha,Motorneuron, Alpha,Motorneurons, Alpha,Neuron, Alpha Motor,Neuron, Motor
D011149	Pons	The front part of the hindbrain (RHOMBENCEPHALON) that lies between the MEDULLA and the midbrain (MESENCEPHALON) ventral to the cerebellum. It is composed of two parts, the dorsal and the ventral. The pons serves as a relay station for neural pathways between the CEREBELLUM to the CEREBRUM.	Pons Varolii,Ponte,Pons Varolius,Pontes,Varolii, Pons,Varolius, Pons
D002467	Cell Nucleus	Within a eukaryotic cell, a membrane-limited body which contains chromosomes and one or more nucleoli (CELL NUCLEOLUS). The nuclear membrane consists of a double unit-type membrane which is perforated by a number of pores; the outermost membrane is continuous with the ENDOPLASMIC RETICULUM. A cell may contain more than one nucleus. (From Singleton & Sainsbury, Dictionary of Microbiology and Molecular Biology, 2d ed)	Cell Nuclei,Nuclei, Cell,Nucleus, Cell
D004247	DNA	A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).	DNA, Double-Stranded,Deoxyribonucleic Acid,ds-DNA,DNA, Double Stranded,Double-Stranded DNA,ds DNA
D005154	Facial Nerve	The 7th cranial nerve. The facial nerve has two parts, the larger motor root which may be called the facial nerve proper, and the smaller intermediate or sensory root. Together they provide efferent innervation to the muscles of facial expression and to the lacrimal and SALIVARY GLANDS, and convey afferent information for TASTE from the anterior two-thirds of the TONGUE and for TOUCH from the EXTERNAL EAR.	Cranial Nerve VII,Marginal Mandibular Branch,Marginal Mandibular Nerve,Seventh Cranial Nerve,Nerve VII,Nerve of Wrisberg,Nervus Facialis,Nervus Intermedius,Nervus Intermedius of Wrisberg,Cranial Nerve VIIs,Cranial Nerve, Seventh,Facial Nerves,Mandibular Nerve, Marginal,Mandibular Nerves, Marginal,Marginal Mandibular Nerves,Nerve VIIs,Nerve, Facial,Nerve, Marginal Mandibular,Nerve, Seventh Cranial,Nerves, Marginal Mandibular,Nervus Faciali,Seventh Cranial Nerves,Wrisberg Nerve,Wrisberg Nervus Intermedius
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
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
D012313	RNA	A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	RNA, Non-Polyadenylated,Ribonucleic Acid,Gene Products, RNA,Non-Polyadenylated RNA,Acid, Ribonucleic,Non Polyadenylated RNA,RNA Gene Products,RNA, Non Polyadenylated