A SIMPLE METHOD USING THE LIGHT-MICROSCOPE TO VISUALIZE SPERMATOZOON TAIL SWELLING IN THE HYPOOSMOTIC TEST

The functional integrity of the sperm (SPTZ) membrane is believed to b e an important factor in fertilization. This function was assessed by Jeyendran et al. (Journal of Reproduction and Fertility, 70: 219-228, 1984), who concluded that when SPTZ from normal fertile men are expose d to a hypo-osmotic solution with an ionic strength of 0.15 mol/l, 60% or more will exhibit tail swelling Essentially no changes have occurr ed in the test procedure since it was first published, except that SPT Z could be fixed after exposure to the hypo-osmotic solution and obser ved at a later time using a phase-contrast microscope. We describe her e a simple test which does not require phase-contrast microscopy to re ad a stained preparation after the hypo-osmotic test. A drop of semen preincubated in the hypoosmotic medium of Jeyendran et al. and fixed w ith 18.5% formalin is placed on an albumin-coated slide. A second (spr eader) slide is placed on the first as a coverslip and pulled forward at moderate speed until all the sperm has been spread into a moderatel y thin film. The preparation is then air dried and submitted to Papani colaou staining. The slide can be read at any time after staining with a light microscope and provides permanent documentation.