Biomaterial Database

Effect of tumor promoters on the response of cultured embryonic chick ganglia to nerve growth factor. 1978

D N Ishii

The tumor-promoting plant diterpene 12-O-tetradecanoyl-phorbol-13-acetate (TPA) inhibits nerve growth factor (NGF)-provoked neurite outgrowth in cultured embryonic chick sensory and sympathetic ganglia. Other plant diterpenes that are tumor promoters on the mouse skin carcinogenesis system also inhibit ganglia response to NGF, but structurally related nonpromoting compounds are inactive. There is no evidence that the inhibitory effect of TPA is due to cytotoxicity. In fact, it appears that TPA can enhance the survival of neuronal and nonneuronal cells in culture. Although neurite outgrowth is prevented, established neurites do not retract in the presence of TPA. After 24 hr, ganglia can slowly overcome the block, even in the presence of fresh TPA; thus, inhibition is transient. The concentration of NGF that does induce a half-maximal neurite outgrowth response in sensory ganglia is approximately 0.6 X 10(-11) M. The antagonism of NGF by TPA is dose dependent and apparently noncompetitive. TPA concentrations that extensively inhibit neurite outgrowth do not affect the amount of 125I-labeled NGF bound to specific sites on dissociated dorsal root ganglion cells, which supports the contention that TPA acts at a stage beyond the initial interaction of the factor with its receptive site.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009414	Nerve Growth Factors	Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.	Neurite Outgrowth Factor,Neurite Outgrowth Factors,Neuronal Growth-Associated Protein,Neuronotrophic Factor,Neurotrophic Factor,Neurotrophic Factors,Neurotrophin,Neurotrophins,Growth-Associated Proteins, Neuronal,Neuronal Growth-Associated Proteins,Neuronotrophic Factors,Neurotrophic Protein,Neurotrophic Proteins,Proteins, Neuronal Growth-Associated,Factor, Neurite Outgrowth,Factor, Neuronotrophic,Factor, Neurotrophic,Factors, Nerve Growth,Factors, Neurite Outgrowth,Factors, Neuronotrophic,Factors, Neurotrophic,Growth Associated Proteins, Neuronal,Growth-Associated Protein, Neuronal,Neuronal Growth Associated Protein,Neuronal Growth Associated Proteins,Outgrowth Factor, Neurite,Outgrowth Factors, Neurite,Protein, Neuronal Growth-Associated
D010703	Phorbol Esters	Tumor-promoting compounds obtained from CROTON OIL (Croton tiglium). Some of these are used in cell biological experiments as activators of protein kinase C.	Phorbol Diester,Phorbol Ester,Phorbol Diesters,Diester, Phorbol,Diesters, Phorbol,Ester, Phorbol,Esters, Phorbol
D010704	Phorbols	The parent alcohol of the tumor promoting compounds from CROTON OIL (Croton tiglium).	Tigliane,Tiglianes
D002470	Cell Survival	The span of viability of a cell characterized by the capacity to perform certain functions such as metabolism, growth, reproduction, some form of responsiveness, and adaptability.	Cell Viability,Cell Viabilities,Survival, Cell,Viabilities, Cell,Viability, Cell
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005724	Ganglia	Clusters of multipolar neurons surrounded by a capsule of loosely organized CONNECTIVE TISSUE located outside the CENTRAL NERVOUS SYSTEM.
D005725	Ganglia, Autonomic	Clusters of neurons and their processes in the autonomic nervous system. In the autonomic ganglia, the preganglionic fibers from the central nervous system synapse onto the neurons whose axons are the postganglionic fibers innervating target organs. The ganglia also contain intrinsic neurons and supporting cells and preganglionic fibers passing through to other ganglia.	Autonomic Ganglia,Ganglion, Autonomic,Autonomic Ganglion