Biomaterial Database

The role of thiamine on excitable membrane of crayfish giant axon. 1976

M Sasa, and I Takemoto, and K Nishino, and Y Itokawa

Electrophysiological and biochemical studies were performed to determine the role of thiamine in the excitable membrane of the crayfish giant axons, as it has been suggested that thiamine plays a role in the excitability of the membrane which is unrelated to the metabolic process. Thiamine (5mM) significantly increased the rising rate of the action potential without affecting the resting membrane potential and threshold potential. A recovery of the enhancement was evidenced by a wash of the axon with physiological solution. Pyrithiamine (10 mM) reduced the rising rate of the action potential without affecting the membrane and threshold potential. The reduction of dV/dt by pyrithiamine remained unchanged after a wash of the axon with physiological solution, while dV/dt increased after thiamine treatment. The amount of thiamine found in the crayfish axons was comparable to that observed in the rat sciatic nerve. In addition, pyrithiamine reduced the thiamine content in axons and protein binding thiamine of the axons. It is thus concluded that thiamine in the excitable membrane of crayfish axons plays a significant role in production of the action potential and is essential for maintaining the membrane excitability of crayfish axons.

UI	MeSH Term	Description	Entries
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D011745	Pyrithiamine	A thiamine antagonist due to its inhibition of thiamine pyrophosphorylation. It is used to produce thiamine deficiency.	Heterovitamin B 1,Neopyrithiamine,1, Heterovitamin B,B 1, Heterovitamin
D003400	Astacoidea	A superfamily of various freshwater CRUSTACEA, in the infraorder Astacidea, comprising the crayfish. Common genera include Astacus and Procambarus. Crayfish resemble lobsters, but are usually much smaller.	Astacus,Crayfish,Procambarus,Astacoideas,Crayfishs
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
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
D013831	Thiamine	3-((4-Amino-2-methyl-5-pyrimidinyl)methyl)-5-(2- hydroxyethyl)-4-methylthiazolium chloride.	Aneurin,Vitamin B 1,Thiamin,Thiamine Mononitrate,Vitamin B1,Mononitrate, Thiamine