Nitric oxide and nitric oxide synthase during early lactation in water buffalo dams

Nitric oxide (NO) production and the presence of nitric oxide synthase (NOS) in the mammary gland of water buffaloes (n=34) was investigated. A local production of NO in the mammary gland during lactation was hypothesized by the presence of high amounts of nitrite plus nitrate (NO 2 - + NO 3 -) in colostrum and milk. The iNOS was the main isoform and was detected in the alveoli epithelial cells. The highest quantities of both NO 2 - + NO 3 - and NOS was detected at the first day of lactation, suggesting an increase of NO production during the synthesis of colostrum. The results suggest that NO is involved in the development of mammary gland and a local NO-generating system may be activated at the onset of lactation.