X-Message-Number: 30347 Date: Tue, 22 Jan 2008 21:33:27 -0800 (PST) From: Subject: The most effective cryoprotectant is ... [Lactamide has outperformed all other cryoprotectants that it has been tested against (see below). However at $17,390 per kilogram it is understandible if this cryoprotectant has never become popular. Compare this price to dimethylsulfoxide's price of $155 per liter.] DL-Lactamide: 10g (Spectum Branded) Category: Fine Chemicals CAS: 65144-02-7 Characteristics: Functional Use: Grade: Details: Formula: C3H7NO2 Formulat Weight: F.W. 89.09 DOT PSN: Storage: Store Below 0?C; keep tightly closed. Keywords: DL-Lactic Acid Amide SKU: L3611-10GM PRICE: 173.90 Dimethyl Sulfoxide, USP: 20L (Spectum Branded) Category: Natural Products/Extracts CAS: 67-68-5 Characteristics: Functional Use: Grade: USP Details: Formula: C2H6OS Formulat Weight: F.W. 78.13 DOT PSN: Storage: LIGHT SENSITIVE, HYGROSCOPIC: Keep tightly closed in light-resistant containers. Keywords: Methyl Sulfoxide; DMSO SKU: D1258-20LT PRICE: 3,109.05 J Reprod Dev. 2006 Aug;52(4):511-6. Epub 2006 May 8. Comparison of glycerol, lactamide, acetamide and dimethylsulfoxide as cryoprotectants of Japanese white rabbit spermatozoa. Kashiwazaki N, Okuda Y, Seita Y, Hisamatsu S, Sonoki S, Shino M, Masaoka T, Inomata T. Laboratory of Animal Reproduction, School of Veterinary Medicine, Azabu University, Japan. The rabbit is considered to be a valuable laboratory animal. We compared glycerol, lactamide, acetamide, and dimethylsulfoxide (DMSO) as cryoprotectants in egg-yolk diluent of ejaculated Japanese white rabbit spermatozoa for improvement of sperm cryopreservation methods. Rabbit semen was frozen with 1.0 M glycerol, lactamide, acetamide, or DMSO in plastic straws. Forward progressive motility and plasma membrane integrity of the post-thaw spermatozoa were examined. The rate of forward progressive motile spermatozoa in lactamide (37.8 +/- 3.0%) was significantly (P<0.05) higher than in glycerol (17.0 +/- 3.3%). In addition, the rates of sperm plasma membrane integrity in lactamide and acetamide (35.9 +/- 3.3% and 30.2 +/- 3.0%, respectively) were significantly (P<0.05) higher than in glycerol (17.0 +/- 2.6%). The results indicate that 1.0 M lactamide and acetamide have higher cryoprotective effects than 1.0 M glycerol for cryopreservation of Japanese white rabbit spermatozoa. PMID: 16679717 J Reprod Fertil. 1980 Sep;60(1):247-52. Cryoprotective effects of some amides on rabbit spermatozoa. Hanada A, Nagase H. Semen was diluted 1:9 with egg yolk-citrate medium containing 0.31--3.1 M (final concentration) formamide, butyramide, acetamide, propionamide, dimethylformamide, lactamide, malomide, ethylene glycol, trimethylene glycol, dimethylsulphoxide (DMSO) or glycerol. After 30 min incubation at 20 degrees C, sperm motility was superior in hypertonic solutions of acetamide, lactamide, dimethylsulphoxide, trimethylene glycol and ethylene glycol. Some of these compounds were added to semen diluted 1:2 in an isotonic egg-yolk-glucose-lactose-raffinose solution and frozen by the pellet method. Relatively good survival of motility was obtained in 1.0 M-DMSO, -lactamide or -acetamide. Dimethylformamide (0.5 M), ethylene glycol (0.5--1.5 M), trimethylene glycol (1.5 M) and propionamide (0.75 M) also gave some protection. Insemination of does with semen frozen and thawed with 1.0 M-DMSO, -lactamide or acetamide gave fertilization rates of 68--88%, and 84% (38/45) of does gave birth to an average of 5.3 young. PMID: 7431324 Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=30347