[Correlations between the indices of the state of the sympathetic-adrenal and of the hypophyseal-adrenal systems and the level of insulin in horses under various exposures].

The research examines the relationship between certain hormonal indices and insulin level in horses, following physical and emotional stresses. Various factors like adrenaline, noradrenaline, cortisol and excretion of catecholamines were analyzed post-exposure to known and unknown emotional factors.

Investigation Process

• The researchers primarily studied the adrenaline, noradrenaline, ACTH (a hormone produced in the pituitary gland), cortisol and insulin contents in the horse’s blood.
• They also assessed the excretion of catecholamines, which are a group of hormones produced in the body’s stress system, through horse’s urine.
• This investigation process took place after the horses had undergone physical and emotional exposure.

Findings of the Study

• The investigation identified the highest activation of the sympathoadrenal system (SAS) and the hypophysioadrenal system (HAS) and corresponding decrease in insulin content after physical training.
• An exciting find was that known emotional exposure, such as the noise of a hippodrome, activated both parts of the SAS and HAS. This shows that familiar emotional stress can trigger these adrenal systems.
• The study also found out that unfamiliar emotional stress, such as exposure to electronic music, caused a strong reaction in the adrenal medulla of horses, which is the inner part of the adrenal gland that secretes hormones to manage stress.
• The analysis of the correlations indicated that the initial hormonal level could predetermine further activation of these systems when exposed to stress. This suggests the presence of a correlation between the baseline hormonal level and the response of the body to stress.

Correlations and Relationships

• The relationship between the hormonal and mediator sections of SAS changes from reciprocal under normal conditions to synchronised activation during physical training. This suggests that one part of SAS can control the level of activity of the other part.
• Moreover, relationships were found between SAS and HAS systems, and between insulin and catecholamine content when exposed to physical and emotional stress. This showcases a complex network and interaction between these hormones and adaptive systems of body when exposed to stress.