ABSTRACT
Objective To study the impact of hypothyroidism on sperm motility in male rat.Methods According to body weight,20 male Wistar rats were randomly divided into control group and hypothyroidism group (1 ml/100 g/day,0.1％ propylthiouracil by intragastric administration for 60 days) 10 rats in eachgroup.Body weight of these rats was observed every 3 days.After the last intragastric administration,all rats were killed.The levels of thyroid hormones [total triiodothyronine (T3),total thyroxine (T4),and thyroid stimulating hormone (TSH)] were measured by radioimmunoassay.Sperm motility parameters[average path velocity(VAP),straight fine velocity (VSL),straightness (STR),amplitude of lateral head displacement (ALH),sperm density(p),curvilinear velocity (VCL),linearity(LIN),wobble (WOB),mean angular deviation (MAD) and beat cross frequency (BCF)] were measured by a WLJY-9000 color-detection system.Results Compared with the control groups[(298.20 ± 12.15) g,(344.00 ± 13.73)g],the weights of hypothyroidism group of the 30 days[(239.00 ± 15.02) g] and the 60 days [(232.67 ± 17.86)g] were significantly lower(t =7.704,11.380,all P ＜ 0.05).The levels of T3[(373.3 ± 101.3) ng/L] and T4 [(4.00 ± 0.89) × 103 ng/ml] of hypothyroidism group were significantly decreased compared with that of the control groups [(1000.0 ± 273.5)ng/L,(44.33 ± 7.84)× 103 ng/L,t =5.262,12.520,all P ＜ 0.05].Level of TSH[(5.77 ± 0.89) × 103 U/L] of hypothyroidism group was significantly increased compared with that of the control group[(1.87 ± 0.70) × 103 U/L,t =8.413,P ＜ 0.05].Values of VAP[(27.45 ± 1.59)μm/s],VSL [(21.08 ± 1.10)μm/s],STR[(70.53 ± 3.48)％] and ALH[(1.96 ± 0.26)μm] of hypothyroidism group were significantly increased compared with that of the control groups[(24.38 ± 2.59)μm/s,(17.99±2.06)μm/s,(65.93 ± 2.71)％,(1.53 ± 0.27)μm,t =2.687,2.404,2.420,3.175,all P ＜ 0.05].p[(5.07 ± 0.74)109/L] of hypothyroidism group was significantly decreased compared with that of the control group [(8.76 ± 1.01)109/L,t =6.463,P ＜ 0.05].VCL[(52.83 ± 5.56)μm/s],LIN[(38.58 ± 3.41)％],WOB[(52.64 ± 3.24)％],MAD [(64.21 ± 6.71) radian/s] and BCF [(8.93 ± 0.62) Hz] of hypothyroidism group were not significantly different compared with that of the control groups[(49.92 ± 6.43) μm/s,(36.52 ± 2.73)％,(52.49 ± 3.49)％,(62.77 ± 7.34)radia/s,(9.32 ± 0.61)Hz,t =0.805,1.089,0.037,0.341,1.033,all P ＞ 0.05].Conclusion Hypothyroidism can affect sperm activity in male rats,decrease sperm density and cause damage to the reproductive system.