The dose and duration of endosulfan exposure were selected based on previous studies in rats.17,22 Sperm Parameter Analysis At the end of the treatment period, the animals were weighed and anesthetized with diethylether. Then, blood samples were collected via cardiac puncture, and their plasmas were separated and used to assay for testosterone and lactate dehydrogenase (LDH). The testes were removed, weighed, rinsed with in ice-cold saline. The relative weight of the

testes was reported as a percentage of Inhibitors,research,lifescience,medical the body weight. A fraction of the testes of each animal was stored at -20°C for malondialdehyde (MDA) determination, while the remaining fraction was used to determine DSP. For determination of DSP, the testes were decapsulated and homogenized for 4 min in 50 mL of phosphate buffer saline (PBS) solution. The number of homogenization resistant sperm nuclei was counted using a hemocytometer. The numbers were then divided by 6.1 (the duration in days of spermatogenic cycle in rats) to determine Inhibitors,research,lifescience,medical DSP.23 To analyze

the sperm Panobinostat mw motility and viability, the left epididymis was excised and placed in pre-warmed Petri dish. Caudal epididymes was minced in 4 ml of pre-warmed PBS at 37˚C. The Inhibitors,research,lifescience,medical minced tissue was placed in a 37˚C incubator for 5 min and then filtered through Inhibitors,research,lifescience,medical nylon mesh. To evaluate the sperm viability, a drop of the Eosin stain was

added to the sperm suspension on the slide, kept for 5 min at 37˚C, and then observed under microscope. The head of the dead spermatozoa was stained with red color while the live spermatozoa unstained with Eosin stain. Sperm viability was expressed as the live sperm percentage of as the total sperm counted. For the analysis of sperm motility, one drop of sperm suspension was placed on a Inhibitors,research,lifescience,medical warmed microscope slide and a cover slip was placed over the droplet. At least 10 microscopic fields were observed at 400 X magnification under a microscope and the percentage of motile sperm was calculated. The degree of sperm maturation was assessed by Aniline Blue (AB) staining. The protamine-rich nuclei of mature spermatozoa which contain abundant arginine and cysteine and low level of lysine STK38 react negatively with aniline blue stain and remain unstained whereas the histone-rich nuclei of immature spermatozoa with abundant lysine were stained by AB.24 To perform this staining, 5 µl of the sperm collected from the epididymis was smeared onto the glass slide and allowed to dry. The smears were fixed in 3% buffered glutaraldehyde in 0.2 M phosphate buffer (pH 7.2) for 30 min. The slides were then stained with 5% aqueous AB mixed with 4% acetic acid (pH 3.5) for 5 min. On each slide 200 sperms were examined for the proportion of sperm with unstained head.