Biomaterial Database

Freeze-etching study of the axosomatic synapses in the rat sensorimotor cortex. 1998

A Bozhilova-Pastirova

Dept. of Anatomy and Histology, Medical University, Sofia, Bulgaria.

The intramembranous structure of axosomatic synapses in the rat sensorimotor cortex was studied by means of thin sections and freeze-etched replicas. In thin sections, symmetric synaptic junctions were located on perikarya of pyramidal and non-pyramidal neurons. In freeze-etched preparations, the postsynaptic neuronal membrane exhibited the same structure as the surrounding nonjunctional membrane on both fracture faces. Probably this is the freeze-etching equivalent of symmetric axosomatic synapses. Asymmetric synapses were found on perikarya of non-pyramidal neurons. In freeze-etched replicas, the postsynaptic non-pyramidal neuronal membrane contains aggregates of particles on the extracellular half (E-face) as an intramembranous equivalent of asymmetric synapses. The particle packing density in these aggregates was measured and compared with that at the E-face of dendritic shaft and dendritic spine membranes. Intramembranous characteristics of the axosomatic synapses in the rat sensorimotor cortex are discussed in terms of plasticity of the synaptic contact zone.

UI	MeSH Term	Description	Entries
D007425	Intracellular Membranes	Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.	Membranes, Intracellular,Intracellular Membrane,Membrane, Intracellular
D009044	Motor Cortex	Area of the FRONTAL LOBE concerned with primary motor control located in the dorsal PRECENTRAL GYRUS immediately anterior to the central sulcus. It is comprised of three areas: the primary motor cortex located on the anterior paracentral lobule on the medial surface of the brain; the premotor cortex located anterior to the primary motor cortex; and the supplementary motor area located on the midline surface of the hemisphere anterior to the primary motor cortex.	Brodmann Area 4,Brodmann Area 6,Brodmann's Area 4,Brodmann's Area 6,Premotor Cortex and Supplementary Motor Cortex,Premotor and Supplementary Motor Cortices,Anterior Central Gyrus,Gyrus Precentralis,Motor Area,Motor Strip,Precentral Gyrus,Precentral Motor Area,Precentral Motor Cortex,Premotor Area,Premotor Cortex,Primary Motor Area,Primary Motor Cortex,Secondary Motor Areas,Secondary Motor Cortex,Somatic Motor Areas,Somatomotor Areas,Supplementary Motor Area,Area 4, Brodmann,Area 4, Brodmann's,Area 6, Brodmann,Area 6, Brodmann's,Area, Motor,Area, Precentral Motor,Area, Premotor,Area, Primary Motor,Area, Secondary Motor,Area, Somatic Motor,Area, Somatomotor,Area, Supplementary Motor,Brodmann's Area 6s,Brodmanns Area 4,Brodmanns Area 6,Central Gyrus, Anterior,Cortex, Motor,Cortex, Precentral Motor,Cortex, Premotor,Cortex, Primary Motor,Cortex, Secondary Motor,Cortices, Secondary Motor,Gyrus, Anterior Central,Gyrus, Precentral,Motor Area, Precentral,Motor Area, Primary,Motor Area, Secondary,Motor Area, Somatic,Motor Areas,Motor Cortex, Precentral,Motor Cortex, Primary,Motor Cortex, Secondary,Motor Strips,Precentral Motor Areas,Precentral Motor Cortices,Premotor Areas,Primary Motor Areas,Primary Motor Cortices,Secondary Motor Area,Secondary Motor Cortices,Somatic Motor Area,Somatomotor Area,Supplementary Motor Areas
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D005613	Freeze Etching	A replica technique in which cells are frozen to a very low temperature and cracked with a knife blade to expose the interior surfaces of the cells or cell membranes. The cracked cell surfaces are then freeze-dried to expose their constituents. The surfaces are now ready for shadowing to be viewed using an electron microscope. This method differs from freeze-fracturing in that no cryoprotectant is used and, thus, allows for the sublimation of water during the freeze-drying process to etch the surfaces.	Etching, Freeze
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
D001369	Axons	Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.	Axon
D013003	Somatosensory Cortex	Area of the parietal lobe concerned with receiving sensations such as movement, pain, pressure, position, temperature, touch, and vibration. It lies posterior to the central sulcus.	Brodmann Area 1,Brodmann Area 2,Brodmann Area 3,Brodmann Areas 1, 2, 3,Brodmann Areas 1, 2, and 3,Brodmann Areas 3, 1, 2,Brodmann Areas 3, 1, and 2,Brodmann's Area 1,Brodmann's Area 2,Brodmann's Area 3,Brodmann's Areas 1, 2, and 3,Brodmann's Areas 3, 1, and 2,Parietal-Opercular Cortex,Primary Somesthetic Area,S1 Cortex,S2 Cortex,SII Cortex,Anterior Parietal Cortex,Gyrus Postcentralis,Post Central Gyrus,Postcentral Gyrus,Primary Somatic Sensory Area,Primary Somatosensory Area,Primary Somatosensory Areas,Primary Somatosensory Cortex,SI Cortex,Second Somatic Sensory Area,Secondary Sensory Cortex,Secondary Somatosensory Area,Secondary Somatosensory Cortex,Area 1, Brodmann,Area 1, Brodmann's,Area 2, Brodmann,Area 2, Brodmann's,Area 3, Brodmann,Area 3, Brodmann's,Area, Primary Somatosensory,Area, Primary Somesthetic,Area, Secondary Somatosensory,Areas, Primary Somatosensory,Brodmanns Area 1,Brodmanns Area 2,Brodmanns Area 3,Cortex, Anterior Parietal,Cortex, Parietal-Opercular,Cortex, Primary Somatosensory,Cortex, S1,Cortex, S2,Cortex, SI,Cortex, SII,Cortex, Secondary Sensory,Cortex, Secondary Somatosensory,Cortex, Somatosensory,Gyrus, Post Central,Gyrus, Postcentral,Parietal Cortex, Anterior,Parietal Opercular Cortex,Parietal-Opercular Cortices,Primary Somatosensory Cortices,Primary Somesthetic Areas,S1 Cortices,S2 Cortices,SII Cortices,Secondary Somatosensory Areas,Sensory Cortex, Secondary,Somatosensory Area, Primary,Somatosensory Area, Secondary,Somatosensory Areas, Primary,Somatosensory Cortex, Primary,Somatosensory Cortex, Secondary,Somesthetic Area, Primary,Somesthetic Areas, Primary
D013569	Synapses	Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.	Synapse
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats
D051381	Rats	The common name for the genus Rattus.	Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus