Comparation between proteins extracted from different seasonal reproductive stages in Lagostomus maximus maximus (Viscacha)

AGUILERA MERLO C; MONCLUS MA; DOMINGUEZ S; FORNÉS MW.

Merlo, San Luis

Congreso; Reunión Conjunta de: XXII Reunión Científica Anual de la Sociedad de Biología de Cuyo y II Reunión Científica de la Sociedad Argentina de Microscopía (SAMIC); 2004

Sociedad de Biología de Cuyo

The viscacha, seasonal rodent, is native of the pampas and Mesopotamia areas of Argentina. The male exhibits an annual reproductive cycle characterized by a short period of gonadal regression in July-August (winter), a recovery period during September-November (spring) and a period of gonadal activity during January-May (summer-autumn). The aim of this work was to determine the different protein expression in capacitated sperm. Sperm were collected from epididymis cauda in HECM-3 medium, and capacitated in the same medium during differents periods (5, 7 and 11 hs). Proteins were obtained according to Laemmli and were separated by 10 % SDS Polyacrylamide gel electrophoresis. The number of sperm in each determination was equivalent. Significant changes associated with seasonal cycles were found. The most intensive bands were observed in samples obtained from May (active period) comparing with the samples corresponding to August (regressed period) and September (recovery period). This seasonal variation in protein expression is correlated with the seasonal morphological changes observed in the epididymis of viscacha and the decrease of sperm number during the gonadal regression.