The Ups and Downs of Firing Rate Homeostasis

Maintaining homeostasis requires that the body continuously maintain its internal conditions. Each physiological condition has a particular set point, from body temperature to blood pressure to levels of certain nutrients. A set point is the physiological value around which the normal range fluctuates. A normal range is a restricted set of values that is optimally healthful and stable. For example, the set point for normal human body temperature is approximately 37°C (98.6°F).

The regulation of heart rate is a complex process controlled by the autonomic nervous system (ANS), hormonal influences, and intrinsic cardiac mechanisms. The ANS has two main components: the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS).
The SNS increases heart rate through the release of norepinephrine and epinephrine, which act on beta-1 adrenergic receptors in the heart. This action increases the rate of depolarization in the sinoatrial (SA) node, the heart's...

Animal organs and organ systems constantly adjust to internal and external changes through a process called homeostasis ("steady state"). Examples of these changes include regulation of the level of glucose or calcium in the blood or internal responses to external temperatures. Homeostasis requires  maintaining an internal dynamic equilibrium:

Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction.
Humoral...

Homeostasis is the maintenance of a stable internal environment within the body, which is crucial for the proper functioning of cells, tissues, organs, and organ systems. The body has various control mechanisms that work together to regulate various physiological parameters such as temperature, blood pressure, pH balance, and fluid balance, to name a few. These control mechanisms are based on feedback loops that can be either positive or negative.
However, sometimes these feedback loops fail,...

In most cases, excessive hormone production is prevented by negative feedback—a loop that starts with a stimulus inducing the release of a particular substance, like a hormone, to maintain a certain level before triggering a signal that results in a decrease in further release of the hormone.