Gastroparesis is your answer which diabetes in the stomach I believe.
Protein, the building blocks of proteins are amino acids, different sequences and combinations of these amino acids result in huge numbers of proteins which have a variety of functions.
Cardiac muscle cells get all the oxygen they need from the coronary arteries. They do not gather oxygen from the blood flowing inside them but from the blood as received from the coronary arteries. Hope this answers the question. Have a nice day.