What effect does neurohormonal activation have in heart failure?

Neurohormonal activation in heart failure plays a crucial role in the body's compensatory mechanisms. When the heart's ability to pump effectively is compromised, neurohormonal systems such as the renin-angiotensin-aldosterone system (RAAS) and the sympathetic nervous system become activated. This activation leads to vasoconstriction and increased blood volume, which help to maintain blood pressure and perfusion to vital organs in the short term.

Specifically, the balance of blood pressure is maintained through mechanisms that involve retention of fluid and constriction of blood vessels, which are critical during the early stages of heart failure. These adaptations can help to stabilize the patient's condition initially but often lead to detrimental effects over time, contributing to the progression of heart failure and associated symptoms.

The other options do not capture the primary effect of neurohormonal activation in heart failure as well. For instance, inhibition of vasodilation runs contrary to the effects of vasoconstriction that typically occurs, while promoting diuresis is not aligned with the water-retaining aspect of neurohormonal activation. Additionally, while subjective symptoms may increase, the statement focuses on hydraulics rather than direct symptomatic effects.