A modified hypotonic treatment for increasing the frequency and quality of meiotic metaphases from spermatocytes of the Syrian hamster.

A modified hypotonic treatment for the spermatocytes of the Syrian hamster (Mesocricetus auratus) has been developed using a micro-osmometer to determine optimum conditions for the frequency and quality of Metaphase I and II figures. A suspension of germinal cells from the tubules is made in 3.2% sodium citrate solution and allowed to stand for 5 minutes. Water is then added until the concentration of the sodium citrate is reduced to 1.4%. This is followed after 15 minutes by fixation and air drying. The number and quality of the metaphase figures is enhanced considerably by this technique. A comparison is made of blood, plasma and testicular osmolality in several animal species and corresponding values for various solutions used for cytogenetic techniques.