Heart Rhythm Disturbances Caused by Injection of Cholinesterase Inhibitor Physostigmine to Rats during the Early...

Area of Science:

• Cardiovascular Physiology
• Neuropharmacology
• Developmental Biology

Background:

• Cholinergic system plays a crucial role in regulating cardiac activity.
• Understanding the maturation of cardiac autonomic control is vital for neonatal health.
• Physostigmine, a cholinesterase inhibitor, can reveal the effects of acetylcholine excess on the heart.

Purpose of the Study:

• To investigate the cardiac and cardiovascular responses to physostigmine in newborn and 16-day-old rats.
• To determine the developmental stage at which cholinergic regulation of cardiac activity matures.
• To compare the magnitude of cardiovascular responses to acetylcholine excess between different postnatal ages.

Main Methods:

• Administration of physostigmine to newborn and 16-day-old rats.
• Monitoring of cardiac activity parameters.
• Analysis of cardiovascular responses to induced acetylcholine excess.

Main Results:

• Both age groups exhibited similar types of cardiovascular responses to physostigmine.
• A significant difference in the magnitude of these responses was observed between the two age groups.
• Newborn rats showed a less pronounced cardiovascular response compared to 16-day-old rats.

Conclusions:

• The maturation of cholinergic structures regulating cardiac activity is largely completed during early postnatal development (by day 16).
• While the qualitative response is similar, the quantitative cardiac adjustments mature postnatally.
• These findings highlight the dynamic development of autonomic cardiovascular regulation in early life.