HYPOOSMOTIC SWELLING TEST (HOST) FOR ASSESSING THE INTEGRITY OF THE MOUSE SPERM MEMBRANE AND ITS RELATIONSHIP WITH OTHER FUNCTIONAL PARAMETERS - EFFECTS OF 2-DEOXYADENOSINE

The mouse is a widely employed experimental model in reproductive biol ogy. In the present work we developed the hypoosmotic swelling test (H OST) in mouse epididymal spermatozoa. The gametes were incubated in 50 , 100, 150, 200 or 250 mOsm solutions for 30, 60 or 90 min. The highes t percentage of swollen sperm was observed at 100 mOsm (68.3 +/- 3.8%; n = 6) at any incubation time. Quality control was performed. A clear positive correlation between percentage of swollen and progressive or motile spermatozoa (r = 0.898 and 0.850 respectively; n = 7) or ferti lization rate (r = 0.838; n = 6) was detected. The addition of 2-deoxy adenosine 2.5 mmol l(-1) after 60 or 180 min preincubation in capacita ting conditions significantly enhanced the percentage of motile cells. This drug did not modify the percentage of swollen sperm. After 180 m in preincubation, the correlation between swollen and motile cells was restored and the fertilization rate significantly increased.