Episodic nature of the delta 4-ene and delta 5-ene steroidogenic pathways and their relationship to the adreno-gonadal axis in stallions.

This study investigates the daily secretory patterns of various hormones in stallions and how they correlate with each other. It concludes that there are episodic fluctuations in the secretion of these hormones, with a significant relationship observed between certain ones.

Objective of the Study

• The researchers aimed to study the daily secretory patterns of testosterone, other 17 beta-hydroxyandrogen, total oestrogens, and total corticoids in stallions.
• The study focused on the episodic or pulsatile nature of these hormone secretions and their correlation with one another.

Methodology

• Seven stallions were involved in the research.
• The research team collected serial blood samples on an hourly basis over a 24-hour period from each animal.

Findings

• The results showed pulsatile fluctuations in plasma hormone levels of all the stallions. This indicates an episodic secretion of corticoids, oestrogens, and androgens at all times in these horses.
• There was a significant correlation observed between the precursor and products of delta 4-ene and delta 5-ene pathways. These pathways are involved in steroid biosynthesis, wherein delta 4-ene leads to the production of cortisol and corticosterone while delta 5-ene leads to the production of androgens and estrogens.
• A notable inverse correlation (r = -0.68; P less than 0.01) was found between total androgens and total corticoids. This implies that, as the total androgen levels increase, the total corticoid levels decrease, and vice versa.

Significance

• The findings of this study are crucial in understanding the hormone secretion patterns in stallions, which has potential implications in various areas such as animal behavior, health, and breeding.
• The observed episodic fluctuations and interdependencies of these hormones provide insights into the effects they may have on physiological functions like metabolism, immune response, stress reaction, reproduction, and growth.