Do most antihypertensive agents have a sympatholytic action?

Area of Science:

• Cardiovascular Physiology
• Neuroendocrinology
• Pharmacology

Background:

• The sympathetic nervous system significantly influences cardiovascular functions.
• Essential hypertension is characterized by pre- and postsynaptic sympathetic dysfunctions.
• These dysfunctions often enhance sympathetic neurotransmission, increasing sympathetic tone and reactivity.

Purpose of the Study:

• To review the role of sympathetic nervous system dysfunction in essential hypertension.
• To examine the alterations in postsynaptic adrenergic receptor balance in hypertension.
• To discuss the implications of chronic sympathetic activation for cardiovascular complications and antihypertensive therapy.

Main Methods:

• Review of studies over the past three decades.
• Analysis of methodologies investigating sympathetic functions.
• Examination of human cardiovascular tissues for adrenergic receptor function.

Main Results:

• Hypertension is associated with enhanced sympathetic neurotransmission and increased sympathetic tone.
• A shift towards alpha1-adrenergic dominance and reduced beta-adrenergic function is observed in cardiovascular tissues.
• Chronic sympathetic activation contributes to cardiovascular complications.

Conclusions:

• Sympathetic nervous system dysfunction, particularly alpha1-adrenergic dominance, is a key feature of hypertension.
• Attenuating sympathetic tone is a critical goal of antihypertensive therapy.
• Current antihypertensive drugs effectively reduce sympathetic activity, especially postsynaptic alpha1-adrenergic functions.