Endocrine stress response in rats subjected to singular orbital puncture while under diethyl-ether anaesthesia

Area of Science:

• Veterinary Medicine
• Animal Physiology
• Endocrinology

Background:

• Assessing animal welfare is crucial in research.
• Diethyl-ether anaesthesia is commonly used but can induce stress.
• The impact of procedures like orbital puncture under anaesthesia requires evaluation.

Purpose of the Study:

• To determine the endocrine stress response in rats undergoing orbital puncture.
• To compare stress hormone levels between rats with and without orbital puncture under diethyl-ether anaesthesia.
• To ascertain if orbital puncture amplifies the anaesthesia-induced stress response.

Main Methods:

• Plasma samples collected via jugular catheter from rats.
• Concentrations of corticosterone, adrenaline, and noradrenaline measured.
• Comparison of hormone levels and return to baseline between anaesthetized rats with and without orbital puncture.

Main Results:

• Diethyl-ether anaesthesia alone caused significant increases in corticosterone, adrenaline, and noradrenaline.
• No significant differences in peak corticosterone and adrenaline levels or their return to baseline were observed between punctured and non-punctured rats.
• A slight decrease in the return rate of plasma noradrenaline to baseline was noted in punctured rats.

Conclusions:

• Diethyl-ether anaesthesia induces a substantial endocrine stress response in rats.
• Orbital puncture does not appear to amplify the stress hormone response induced by diethyl-ether anaesthesia.
• The pronounced effects of diethyl-ether anaesthesia may mask any additional stress from orbital puncture.