The term "anodal opening tetanus" may sound complicated, but its spelling is actually quite simple when broken down phonetically. "Anodal" is pronounced as [æ'nəʊdəl], with the emphasis on the first syllable and the "a" being pronounced as "æ". "Opening" is pronounced as ['əʊpənɪŋ], with the stress on the second syllable and the "o" being pronounced as [əʊ]. Finally, "tetanus" is spelled as [ˈtɛtənəs], with the stress on the first syllable and the "a" being pronounced as [ə]. Put it all together and you have "ænəʊdəl 'əʊpənɪŋ ˈtɛtənəs".
Anodal opening tetanus is a term used in the field of neuromuscular physiology to describe a phenomenon that occurs during electrical stimulation of a muscle. It refers to the sustained contraction of a muscle fiber upon repeated stimulation with short-duration electrical pulses, specifically when the anode (positive electrode) is placed closest to the muscle fiber.
In normal muscle stimulation, a single electrical pulse triggers a brief contraction of the muscle fiber, followed by relaxation. However, during anodal opening tetanus, rapid and repetitive stimulation with short-duration pulses at the anode causes the muscle fiber to remain in a contracted state without relaxation.
This phenomenon is believed to occur due to the accumulation of intracellular calcium ions within the muscle fiber. As the electrical pulses at the anode depolarize the muscle fiber, calcium ions are released from intracellular stores, leading to a sustained contraction. The continuous influx of calcium ions into the fiber keeps the contractile machinery activated, preventing relaxation.
Anodal opening tetanus is commonly used in experimental studies to investigate the properties and characteristics of skeletal muscle fibers. Understanding the factors that influence the occurrence and maintenance of anodal opening tetanus can provide valuable insights into the mechanisms underlying muscle contraction and the function of the neuromuscular system as a whole.
A tonic contraction in a muscle, to which the anode is applied, when the circuit is opened.
A practical medical dictionary. By Stedman, Thomas Lathrop. Published 1920.