Decreased Anti-Müllerian hormone and Anti-Müllerian hormone receptor type 2in hypothalami of old Japanese Black cows

摘要

Cow fertility decreases with age, but the hypothalamic pathomechanisms are notunderstood. Anti-Müllerian hormone (AMH) stimulates gonadotropin-releasing hormone (GnRH)neurons via AMH receptor type 2 (AMHR2), and most GnRH neurons in the preoptic area (POA),arcuate nucleus (ARC), and median eminence (ME) express AMH and AMHR2. Therefore, wehypothesized that both protein amounts would differ in the anterior hypothalamus(containing the POA) and posterior hypothalamus (containing the ARC and ME) between youngpost-pubertal heifers and old cows. Western blot analysis showed lower( <0.05) expressions of AMH and AMHR2 in the posterior hypothalamus,but not in the anterior hypothalamus, of old Japanese Black cows compared to youngheifers. Therefore, AMH and AMHR2 were decreased in the posterior hypothalami of oldcows.