Neutral alpha-glucosidase activity in mouse: a marker of epididymal function?

MARTINI AC; MOLINA RI; VINCENTI LM; SANTILLÁN ME; STUTZ G; RUIZ RD; FIOL DE CUNEO M

REPRODUCTION FERTILITY AND DEVELOPMENT

CSIRO PUBLISHING

Año: 2007 vol. 19 p. 563 - 568

1031-3613

Neutral alpha-glucosidase (NAG) activity is considered a functional marker of epididymis in several species, including humans. Although NAG has been found in rat epididymis, no enzyme activity has been detected in mice. The objectives of our study were to evaluate NAG activity in mice epididymis and the feasibility of using it as functional epididymal marker. Epididymis (whole or in parts) were incubated in presence or absence of testosterone (10-5 M) and secretory NAG activity was compared with known positive controls. Furthermore, we compared enzyme activity in epididymis from well-fed or undernourished mice (50% food restriction for 21 days), a model that alters epididymal maturation processes.Spectophotometer NAG activity evaluation revealed that: there exist NAG activity in mice epididymis (22.6 +- 3.7 mU/g tissue; n=4), being higher in the caput. NAG activity was statistically higher in the caput than in corpus and in cauda. No significant differences existed between the caput NAG activity and complete epididymis NAG activity. In undernourished mice, we confirmed the epididymal maturation alterations previously observed in our laboratory (increase in immature spermatozoa and diminution in sperm concentration). Concordantly, their epididymis exhibited lesser enzyme activity, which increased to values similar than controls with the addition of testosterone to the incubation medium (22.5 +- 2.6, 12.5 +- 1.0 and 22.4 +- 3.7 mU/g tissue; in controls n=7, underdernourished n=9 and undernourished+testosterone n=9, respectively).In conclusion, we detected NAG activity in mice epididymis and it can be considered as a functional epididymal marker.