Experimental study of sensitization to catecholamines after lumbar sympathectomy

Area of Science:

• Cardiovascular Physiology
• Autonomic Nervous System
• Surgical Research

Background:

• Lumbar sympathectomy is a surgical procedure affecting the sympathetic nervous system.
• Catecholamines, such as epinephrine and norepinephrine, play crucial roles in cardiovascular regulation.
• Understanding the physiological responses post-sympathectomy is vital for clinical applications.

Purpose of the Study:

• To investigate the supersensitivity to catecholamines following lumbar sympathectomy.
• To establish a protocol for studying these phenomena in arteritic patients.
• To assess the duration and potential adverse effects of this sensitization.

Main Methods:

• Intravenous injections of standardized doses of epinephrine and norepinephrine.
• Comparative analysis of electrocardiogram (E.C.G.), arterial blood pressure, and rheographic records.
• Measurements conducted before and at intervals after lumbar sympathectomy in dogs and arteritic patients.

Main Results:

• Demonstrated significant supersensitivity to catecholamine action post-lumbar sympathectomy.
• Observed lasting sensitization for up to 4 months after the operation.
• Identified compensating reflex reactions to arterial hypertension, leading to improved blood flow in denervated areas.

Conclusions:

• Lumbar sympathectomy induces a temporary, non-noxious supersensitivity to catecholamines.
• This sensitization elicits beneficial reflex responses, enhancing blood flow in denervated territories.
• The findings support a potential therapeutic application in managing vascular conditions.