Biomaterial Database

N-type and L-type calcium channels are present in nerve growth cones. Numbers increase on synaptogenesis. 1991

A J Vigers, and K H Pfenninger

Department of Cellular and Structural Biology, University of Colorado Health Sciences Center, Denver 80262.

We have demonstrated the presence of both N- and L-type calcium channels in growth cone and other subcellular fractions of fetal rat brain, using the ligands omega-conotoxin GVIA for N-type channels and nitrendipine for L-type channels. The N-type channels seem to be distributed evenly throughout the perikaryon, neurite shaft and growing tip of the neurons. In contrast, the L-type channels appear to have a lower density in the growth cone than on the rest of the neuron. These observations apply at least within the limitations of cell fractionation technology. We have also studied both calcium channel subtypes in rat brain synaptosomal membranes. In both adult and fetal fractions there are approximately 6 times more N-type than L-type channels. Synaptosomal membranes contain more N- and L-type channels than any of the fetal subfractions, indicating that there is a substantial increase in calcium channel numbers upon synaptogenesis.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009568	Nitrendipine	A calcium channel blocker with marked vasodilator action. It is an effective antihypertensive agent and differs from other calcium channel blockers in that it does not reduce glomerular filtration rate and is mildly natriuretic, rather than sodium retentive.	Balminil,Bay e 5009,Bayotensin,Baypresol,Baypress,Gericin,Jutapress,Nidrel,Niprina,Nitre AbZ,Nitre-Puren,Nitregamma,Nitren 1A Pharma,Nitren Lich,Nitren acis,Nitrend KSK,Nitrendepat,Nitrendi Biochemie,Nitrendidoc,Nitrendimerck,Nitrendipin AL,Nitrendipin Apogepha,Nitrendipin Atid,Nitrendipin Basics,Nitrendipin Heumann,Nitrendipin Jenapharm,Nitrendipin Lindo,Nitrendipin Stada,Nitrendipin beta,Nitrendipin-ratiopharm,Nitrendipino Bayvit,Nitrendipino Ratiopharm,Nitrensal,Nitrepress,Tensogradal,Trendinol,Vastensium,nitrendipin von ct,nitrendipin-corax,Nitre Puren,NitrePuren,Nitrendipin ratiopharm,Nitrendipinratiopharm,nitrendipin corax,nitrendipincorax
D010456	Peptides, Cyclic	Peptides whose amino acid residues are linked together forming a circular chain. Some of them are ANTI-INFECTIVE AGENTS; some are biosynthesized non-ribosomally (PEPTIDE BIOSYNTHESIS, NON-RIBOSOMAL).	Circular Peptide,Cyclic Peptide,Cyclic Peptides,Cyclopeptide,Orbitide,Circular Peptides,Cyclopeptides,Orbitides,Peptide, Circular,Peptide, Cyclic,Peptides, Circular
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D005333	Fetus	The unborn young of a viviparous mammal, in the postembryonic period, after the major structures have been outlined. In humans, the unborn young from the end of the eighth week after CONCEPTION until BIRTH, as distinguished from the earlier EMBRYO, MAMMALIAN.	Fetal Structures,Fetal Tissue,Fetuses,Mummified Fetus,Retained Fetus,Fetal Structure,Fetal Tissues,Fetus, Mummified,Fetus, Retained,Structure, Fetal,Structures, Fetal,Tissue, Fetal,Tissues, Fetal
D005865	Gestational Age	The age of the conceptus, beginning from the time of FERTILIZATION. In clinical obstetrics, the gestational age is often estimated from the onset of the last MENSTRUATION which is about 2 weeks before OVULATION and fertilization. It is also estimated to begin from fertilization, estrus, coitus, or artificial insemination.	Embryologic Age,Fetal Maturity, Chronologic,Chronologic Fetal Maturity,Fetal Age,Maturity, Chronologic Fetal,Age, Embryologic,Age, Fetal,Age, Gestational,Ages, Embryologic,Ages, Fetal,Ages, Gestational,Embryologic Ages,Fetal Ages,Gestational Ages
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
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
D015220	Calcium Channels	Voltage-dependent cell membrane glycoproteins selectively permeable to calcium ions. They are categorized as L-, T-, N-, P-, Q-, and R-types based on the activation and inactivation kinetics, ion specificity, and sensitivity to drugs and toxins. The L- and T-types are present throughout the cardiovascular and central nervous systems and the N-, P-, Q-, & R-types are located in neuronal tissue.	Ion Channels, Calcium,Receptors, Calcium Channel Blocker,Voltage-Dependent Calcium Channel,Calcium Channel,Calcium Channel Antagonist Receptor,Calcium Channel Antagonist Receptors,Calcium Channel Blocker Receptor,Calcium Channel Blocker Receptors,Ion Channel, Calcium,Receptors, Calcium Channel Antagonist,VDCC,Voltage-Dependent Calcium Channels,Calcium Channel, Voltage-Dependent,Calcium Channels, Voltage-Dependent,Calcium Ion Channel,Calcium Ion Channels,Channel, Voltage-Dependent Calcium,Channels, Voltage-Dependent Calcium,Voltage Dependent Calcium Channel,Voltage Dependent Calcium Channels