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

Buenos Aires, Argentina

Congreso; XXII Congreso Latinoamericano y I Congreso Ibero-americano de Ciencias Fisiológicas; 2006

Sociedad Argentina de Fisiología

Neutral alpha-glucosidase activity in mouse: a marker of epididymal function. Martini Ana Carolina, Molina Rosa I, Vincenti Laura M, Santillán María Emilia, Stutz Graciela, Ruiz Rubén D, Fiol de Cuneo Marta. Instituto de Fisiología, Fac Cs Méd, Universidad Nacional de Córdoba. Lab Androl Reprod (LAR). Córdoba, Argentina. 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. To evaluate mouse NAG activity, epididymis (whole or in parts) were incubated in presence or absence of testosterone (T; 10-5 M) and compared with known positive controls. To explore the feasibility of using mouse epididymal NAG activity as functional marker, we compared enzyme activity from well-fed or undernourished mice (50% food restriction for 21 days), model that alters epididymal sperm maturation processes. Activity of NAG (evaluated by a spectrophotometric technique) revealed that: there exists NAG activity in mice epididymis, being higher in the caput portion (caput: 30.7±4.2, corpus: 11.7±2.8 and cauda: 10.6±4.4 mU/g of tissue; n=4, caput vs corpus or cauda: p< 0.05). In undernourished mice, we confirmed the epididymal sperm maturation alterations previously observed in our laboratory (increase in immature spermatozoa and diminution in sperm concentration); concordantly, epididymal NAG activity was lesser than in control ones and it increased by addition of T to the incubation medium (control: 22.47±2.59, n=7; 50 % undernourished: 12.45±0.98, n=9; 50 % undernourished + T: 22.45±3.73 mU/g of tissue, n=9; p< 0.05 vs 50 % undernourished). In conclusion, in mice epididymis we detected NAG activity; moreover, changes in such enzyme activity could be responsible –among other factors-, for the alterations in sperm epididymal maturation processes previously described in undernourished mice. Grants from SECyT-UNC and Agencia Córdoba Ciencia .SE.