Hypotonic KCl: An improved method of processing human testicular tissue for meiotic chromosomes

A suspension was made in isotonic Hanks solution of the contents of the tubules from a human testicular biopsy specimen. The germinal cells were sedimented by centrifugation and the supernatant was discarded. The cells were resuspended in hypotonic (0.42%) potassium chloride, left at 37oC for 20 minutes, then centrifuged again, and fixed in a mixture of 2 parts absolute methanol and 1 part glacial acetic acid. Air-dried preparations were made from the final suspension and stained in Giemsa solution. This method is suitable for all the stages of male meiosis. Its main advantage lies in the property of KCl which avoids cell clumps and unpredictable failures presumably related to the formation of a coagulum in the cellular suspension. KCl has been used advantageously to prepare meiotic cells with improved spreading and staining of the chromosomes.