The body has quite a number of regulatory systems and many of these can affect the circulation. That is not the topic here. The various regulations operate through changing parameters of the circulation model. This page is about which parameters and how their changes affect the outcome of the model.
Parameters were: compliances C, periferal resistances TPR and Rp, and properties of the heart, in particular, the systolic curve(s). But there are also indirect influences, the most obvious one being the (blood) volume - more volume implies higher pressures - and any regulatory system affecting the volume will also influence blood pressures. The body must counteract with another regulating system. So, treatment of low or high blood pressure can be quite complicated.
As said before, a computer model is needed for calculations on the system, but some results are quite understandable. Lets start with the compliances C. These must be high to allow blood vessel volumes to vary enough without too much change in pressure. In particular, if aortic compliance is too low, the highest - systolic - pressure will go up and the lowest - diastolic - down.
Also, resistance is straightforward: a high resistance means high pressure before, so high pressures in the arteries. Also here, the pressure after the resistance will decrease but only minor because venous pressures are low anyhow.
Finally, the heart. Here, two regulations are possible: frequency and strength. Both can be regulated but the effects depend on the simultaneous co-regulations. Regulation of strength is by shifting the systolic curve upward; the diastolic curve is hardly or not affected.
Since the important regulations are to the systemic cirulation it is possible to incorporate regulations already in the basic model.
Conclusion:
Incorporating regulations in the circulation model at least should involve
influencing:
– heart rate
– systolic curve of the left heart
– total blood volume
– systemic arterial compliance
– Total Peripheral Resistance