. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100- 50- ASW. 20 40 20 40 60 80 Minutes FIGURE 2. Effects of procaine on motility of Arbacia sperm suspended in a) FSW and b) MBL- ASW. Ordinate, percent of control motility rate; abscissa, time elapsed following dilution. Note that procaine-treated sperm suspended in MBL-ASW swim at a higher rate of speed for longer periods than do similarly treated sperm in FSW. phosphatase, is considered to impede Ca2+ efflux from cardiac muscle cells (Wood et al., 1972) and may similarly affect sperm cells (cf. review, Nelson and McGrady
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100- 50- ASW. 20 40 20 40 60 80 Minutes FIGURE 2. Effects of procaine on motility of Arbacia sperm suspended in a) FSW and b) MBL- ASW. Ordinate, percent of control motility rate; abscissa, time elapsed following dilution. Note that procaine-treated sperm suspended in MBL-ASW swim at a higher rate of speed for longer periods than do similarly treated sperm in FSW. phosphatase, is considered to impede Ca2+ efflux from cardiac muscle cells (Wood et al., 1972) and may similarly affect sperm cells (cf. review, Nelson and McGrady, 1981). The maximum effect of a 10-min incubation in ouabain in filtered sea water occurs at about 10~6 M. This is shown in Figure 3 and confirms the previous report (Nelson, 1972). Increasing the incubation periods in MBL-ASW shifts the maximum response to the left; incubation in 10~9 M ouabain produces a peak in 30 minutes. This is again a dramatic ( fold) increase over that of the initial rate of the FSW controls. Ouabain toxicity in the mammalian heart cell may be counteracted by the beta- adrenergic-blocking agent propranolol (which in itself exhibits some of the Ca-per- turbing properties of a local anesthetic). Propranolol and ouabain were therefore assayed singly and in combination; their interactive effects were tested on the pro- gressive motility of sperm in filtered sea water. Lower concentrations of propranolol have little effect except for a 20% increase at 10 6 M (Fig. 4). However, at mM a 40% decrease in motility occurs, while the inhibition increases to 80% at 1 mM. The peak effect of ouabain alone (at 10~6 M) was a 65% increase in the swimming rate over the controls. In the optimum concentration of ouabain (10 6 M), increasing amounts of propranolol tend to lower the motility response curve by about 5-10%. Above the optimum concentration of both drugs (10~6 M each), the ouabain did not significantly influence the response to propranolol. However, with
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
