The Modulation of Sperm Function by the Oviductal Epithelium(4)

Moreover, the effects of oAMV on sperm viability were tissue specific and were related to the hormonal status of the oviductal tissue at the time of collection. In addition, the viability-maintaining effect of equine oAMV was significantly reduced in the presence of antibody fragments that reduced oAMV binding to sperm, thus suggesting that a specific interaction between sperm and oAMV is required to mediate this effect (Fig. 2). ventolin inhaler

Direct contact between sperm and the apical plasma membrane of oviductal cells also appears to slow the rate of sperm capacitation. When equine sperm were incubated with oAMV derived from preovulatory isthmic oviductal epithelial cells, the percentage of capacitated sperm was significantly lower at 6 and 24 h than that of sperm incubated in capacitating medium alone or with oAMV in the presence of Fab that reduce oAMV binding to sperm (Fig. 3). When human sperm were incubated with oAMV derived from premenopausal women for up to 48 h, a similar pattern was observed. Under these conditions, human sperm capacitation was delayed by approximately 24 h but eventually reached control levels. These data suggest that sperm interaction with the apical plasma membrane of oviductal epithelial cells may provide a mechanism through which the timing of capacitation can be modulated in vivo. The biochemical basis for this modulation is unclear but is probably related to the regulation of sperm intracellular calcium.
Fig2The modulation of sperm
FIG. 2. Percentage of viable equine spermatozoa incubated with or without isolated isthmic oAMV in the presence or absence of antibody fragments (Fab) raised against equine periacrosomal sperm plasma membrane or antibody fragments from nonimmunized rabbit serum (cFab). Medium for culture was Tyrode’s albumin lactate pyruvate medium (TALP). Means ± SD, n = 6 ejaculates. Transformed data (1/sqrt[x|) were analyzed by ANOVA for the effects of time, treatment, and interactions. Pair-wise comparisons of means were made using Tukey’s studentized range test (HSD). Means with different letters are significantly different (p < 0.05). Adapted from Dobrinski et al., Biol Reprod 1997; 56:866, Figure 5a.

Fig3The modulation of sperm
FIG. 3. Percentage of capacitated equine spermatozoa incubated with or without isolated isthmic oAMV in the presence or absence of antibody fragments (Fab) raised against equine periacrosomal sperm plasma membrane or antibody fragments from nonimmunized rabbit serum (cFab). Medium for culture was Tyrode’s albumin lactate pyruvate medium (TALP). Means ± SD, n = 6 ejaculates. Transformed data (1/sqrt[x]) were analyzed by ANOVA for the effects of time, treatment, and interactions. Pair-wise comparisons of means were made using Tukey’s studentized range test (HSD). Means with different letters are significantly different (p < 0.05). Adapted from Dobrinski et al., Biol Reprod 1997; 56:866, Figure 5b.

This entry was posted in Sperm and tagged Epithelium, Modulation, Oviductal, Sperm Function.