Preparation and maintenance of living house cricket (Acheta domesticus) spermatocytes.

A simple and efficient method for the maintenance of Acheta domeslicus spermatocytes in vitro while permitting microscopic observation during meiotic maturation is described. The method allows the study of the factors effecting normal maturation and is applicable to other organisms. Three media are described: MM 100 contains only salts in the concentrations found in Acheta hemolymph; MMIOI contains in addition, amino acids; MMIO2 contains sugars, vitamins and peptone as well. In the first medium (MMIOO) diplotene primary spermatocytes developed to metaphase II and spermatocytes in metaphase I completed meiosis II, but not consistently. Development to metaphase II was more consistent in the second medium (MMIO1). In the third medium spermatocytes in the diplotene state rarely reached metaphase I while spermatocytes in diakinesis always developed to metaphase II. The optimal tonicity of all the media was 320 milliosmoles. The spermatocytes appear to tolerate the high concentrations of magnesium and calcium present in media MMIOO and MM 101 and also the low concentration present in medium MM 102 where tonicity was maintained by the addition of carbohydrates and peptone.