Aldosterone-progesterone relationship in sexually intact Chihuahua bitches

Abstract Background Aldosterone represents an important target of heart failure therapy and may be a valuable indicator of the renin-angiotensin-aldosterone system activity. However, its assessment might be challenging because of the effect of individual factors. In a recent study, intact female dogs showed the highest value of urinary aldosterone-to-creatinine ratio (UAldo:C) compared to other sex categories. In humans and rodents, an influence of progesterone has been reported by several studies. To our knowledge, the relationship between aldosterone and progesterone has not yet been investigated in dogs. The aim of this prospective study was to investigate this relationship in sexually intact Chihuahua females, measuring both hormones twice in the same bitch, that is in anoestrus when progesterone concentrations are baseline and in dioestrus when they are high. Results The study population consisted of 14 sexually intact Chihuahua bitches. Serum progesterone (34.06 (21.17–44.90) vs. 0.19 [0.13–0.38] ng/ml; P