Final answer:
Positive inotropic agents, like NE, can increase the maximum load on the length-tension curve in the heart.
Step-by-step explanation:
Positive inotropic agents, such as norepinephrine (NE), can have an effect on the maximum load on the length-tension curve in the heart. These agents increase the strength of contraction by stimulating the influx of calcium ions into the cardiac muscle cells, which leads to greater force production. This means that with the presence of NE, the heart can generate a higher maximum load on the length-tension curve.