Assessment of Platelet and Plasma Serotonin in Canine Pulmonary Hypertension Secondary to Degenerative Mitral Valve Disease.

Abstract

Pulmonary hypertension (PH) is a common complication of degenerative mitral valve disease (DMVD), the most common cardiovascular disease in dogs. Serotonin has been suspected to play a role in the pathogenesis of PH, so this study aimed to investigate the differences in platelet and plasma serotonin between normal, DMVD and DMVD with PH (DMVD+PH) dogs.Sixty-two small-breed dogs were enrolled to the study and divided into the normal (= 22), DMVD (= 20), and DMVD+PH (= 20) groups. The platelet and plasma serotonin concentrations were measured by the competitive ELISA.The Kruskal-Wallis revealed the difference among the four groups of normal (179.73 [102.37-352.24] ng/10platelets), DMVD (325.99 [96.84-407.66] ng/10platelets), DMVD with intermediate probability of PH (291.11 [106.69-400.84] ng/10platelets) and DMVD with high probability of PH (35.82 [2.69-126.35] ng/10platelets) (= 0.014). The Dunn'stest showed a decrease in the platelet serotonin concentration of the DMVD dogs with high probability of PH compared to the DMVD group (= 0.008). The plasma serotonin concentration was not different between normal, DMVD, and DMVD+PH dogs.In conclusion, a decrease in platelet serotonin concentration, which is associated with a degree of PH probability was found in DMVD dogs with PH. Further studies investigating roles of platelet serotonin in PH secondary to DMVD should be performed.