Neural and Hormonal Control of Cardiac Activity

Flashcards on neural and hormonal control of cardiac activity.

Extrinsic Control

Signals that exert control or regulation of an organ come from outside that organ.

Intrinsic Regulation

Stimuli for changes in activity of the organ originate from within that organ itself.

Cardiac Accelerator Nerves

Branches of specific sympathetic nerves that innervate and form synapses with various parts of the heart.

Sympathetic Nerves Function

Communicate with conductive and contractile cells, influencing both the rate and force of heart contraction.

Parasympathetic Nerve Branches

Innervate SA nodal and AV nodal cells, influencing heart rate but not directly affecting the force of ventricular contraction.

Norepinephrine

The primary neurotransmitter used by postganglionic sympathetic neurons.

Adrenergic Receptors

Receptors that bind to norepinephrine and/or epinephrine.

Beta One Adrenergic Receptor

Full name for the receptor subtype on the heart muscle that binds norepinephrine/epinephrine.

Contractility

The effect that the sympathetic system has on the contractile myocardium, making it contract with more force.

Acetylcholine

The primary neurotransmitter used by postganglionic parasympathetic neurons.

Cholinergic Receptor

Any receptor that is able to bind to acetylcholine.

Muscarinic Receptor

A subtype of cholinergic receptor on the heart muscle that has an inhibitory effect, helping to slow the heart rate down.

Epinephrine

Hormone that is able to bind and activate beta one adrenergic receptors, similar to norepinephrine.