Griffin P G, Ginther O J
Department of Veterinary Science University of Wisconsin-Madison Madison, WI 53706 USA.
Theriogenology. 1993 May;39(5):997-1008. doi: 10.1016/0093-691x(93)90001-l.
One-minute continuous ultrasonic scans of longitudinal sections of the uterine body were videotaped, and contractility scores (1 to 5, minimal to maximal contractility) were assigned without knowledge of mare identity, day of the estrous cycle or pregnancy status. Contractility was assessed, and plasma progesterone concentrations were determined for each of 3 daily examinations (at 0800, 1600 and 2400 hours) from Day 9 to Day 19 (Day 0 = day of ovulation). For both the nonbred (n=11) and pregnant (n=11) mares, there was no effect of hour of scan on the extent of uterine contractility. When data for the nonbred mares were normalized to the onset of luteolysis (defined for each mare as the first >/=25% decrease in plasma progesterone concentrations between successive samples), there was an abrupt increase (P<0.05) in contractility 24 hours prior to the onset of luteolysis. Contractility was also assessed daily in 20 nonbred and 27 pregnant mares from Day 0 to Day 17. For the nonbred mares, a biphasic profile in contractility occurred during the estrous cycle as indicated by the following significant changes: a decrease between Days 0 and 2, an increase between Days 2 and 4, a plateau between Days 4 and 7, a decrease between Days 7 and 11, an increase between Days 11 and 13, and a decrease between Days 14 and 16. For pregnant mares, contractility increased (P<0.05) prior to the late-diestrous increase for nonbred mares. In addition, a significant reduction in contractility was detected on Day 5 in these mares compared with that in the nonbred mares. Contractility in the uterine body in 7 mares was assessed every 5 minutes after departure of the embryonic vesicle from the uterine body. Levels of contractility in the uterine body were lower (P<0.05) 55 minutes after the vesicle had exited the body than </= 5 minutes after exit. Mean contractility scores in the body decreased in a linear fashion (r(2)=0.77; P<0.0001) over the 60 minutes following vesicle exit. Contractility was enhanced in the uterine body when the embryonic vesicle was present and then progressively decreased with time after the vesicle departed from the uterine body.
对子宫体纵切面进行一分钟的连续超声扫描并录像，在不知道母马身份、发情周期天数或妊娠状态的情况下给出收缩力评分（1至5分，收缩力从最小到最大）。从第9天到第19天（第0天=排卵日），每天进行3次检查（分别在08:00、16:00和24:00），评估收缩力并测定血浆孕酮浓度。对于未受孕母马（n = 11）和怀孕母马（n = 11），扫描时间对子宫收缩力程度均无影响。当将未受孕母马的数据以黄体溶解开始时为基准进行标准化处理（将每匹母马连续样本间血浆孕酮浓度首次下降≥25%定义为黄体溶解开始），在黄体溶解开始前24小时收缩力出现突然增加（P<0.05）。从第0天到第17天，还对20匹未受孕母马和27匹怀孕母马的收缩力进行了每日评估。对于未受孕母马，发情周期中收缩力呈双相变化，具体表现为以下显著变化：第0天至第2天下降，第2天至第4天增加，第4天至第7天平稳，第7天至第11天下降，第11天至第13天增加，第14天至第16天下降。对于怀孕母马，在未受孕母马发情后期收缩力增加之前，其收缩力就已增加（P<0.05）。此外，与未受孕母马相比，这些怀孕母马在第5天收缩力显著降低。在胚泡离开子宫体后，对7匹母马子宫体的收缩力每5分钟评估一次。胚泡离开子宫体55分钟后的子宫体收缩力水平低于离开后≤5分钟时（P<0.05）。在胚泡离开后的60分钟内，子宫体的平均收缩力评分呈线性下降（r² = 0.77；P<0.0001）。当胚泡存在时子宫体收缩力增强，胚泡离开子宫体后随时间逐渐下降。
