who discovered it?
H Reuter and N Seitz.
Sodium-calcium exchanger
In 1968, H Reuter and N Seitz 
the function of the transverse tubules is to T-tubules permit rapid transmission of the action potential into the cell, and also play an important role in regulating cellular calcium concentration. when was it first introduced? They were discovered in 1897. what is it's significance clinically? They may be lost or disrupted following a myocardial infarction, and are also disrupted in the ventricles of patients with heart failure, contributing to reduced force of contraction and potentially decreasing the chances of recovery. why is the control of calcium important in this case? To continue cardiac contraction. does it lead to any type of failure? Yes, heart failure. name some of it's symptoms? Shortness of breath, excessive tiredness, and leg swelling. how can it be diagnosed? The National Institute for Health and Care Excellence recommends measuring brain natriuretic peptide (BNP) followed by an ultrasound of the heart if positive. This is recommended in those with shortness of breath. In those with worsening heart failure, both a BNP and a troponin are recommended to help determine likely outcomes. what is the structure of the former mentioned tubule They are formed of a phospholipid bilayer. They have sections running both perpendicular (transverse) to and parallel (axially) to sarcolemma.The membrane that forms T-tubules is highly active, being studded with proteins including L-type calcium channels, sodium-calcium exchangers, calcium ATPases and Beta adrenoceptors. name some uses of the exchanger. It  is only one of the systems by which the cytoplasmic concentration of calcium ions in the cell is kept low.
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Sodium-calcium exchanger [SEP] History
In 1968, H Reuter and N Seitz published findings that, when Na is removed from the medium surrounding a cell, the efflux of Ca is inhibited, and they proposed that there might be a mechanism for exchanging the two ions. In 1969, a group led by PF Baker that was experimenting using squid axons published a finding that proposed that there exists a means of Na exit from cells other than the sodium-potassium pump. Digitalis, more commonly known as foxglove, is known to have a large effect on the Na/K ATPase, ultimately causing a more forceful contraction of the heart.