Identification of the uterine factor(s) which induce the acrosome reaction in buffalo (Bubalus bubalis) spermatozoa

This study characterizes factors present in uterine fluid from oestrous buffaloes which induce the acrosome reaction in buffalo spermatozoa. Characterization was performed by dialysis, heat treatment (90 degrees C, 30 min) and deproteinization of uterine fluid. The % motility and viability of sperm was maintained better in unfractionated uterine fluid than in dialysed fluid. Heating and deproteinization of the dialysed uterine fluid significantly reduced the % motility and viability of sperm. The percentage of sperm showing different stages of the acrosome reaction (swelling, and vesiculation) was significantly higher for sperm incubated in dialysed than in neat uterine fluid. There was no significant difference in the % of sperm showing acrosome shedding in both dialysed and neat uterine fluid. Heat treatment destroyed the ability of uterine fluid to induce the acrosome reaction. Sperm incubated in the protein precipitate from uterine fluid showed all stages of the acrosome reaction. Thus, the uterine factor(s) responsible for inducing the acrosome reaction in buffalo sperm was associated with the non-dialysable, albumin-like protein fraction and was heat-labile.

["In vitro" stimulation of TBArs. Production by carbon tetrachloride in MH1C1 hepatoma (author's transl)]

It is well known that lipid peroxidation is absent or extremely low in tumour tissues. So the lack of lipid peroxidation is so far considered as a peculiar characteristic of tumour cells. Studying lipid peroxidation in three different hepatomas, we have found, however, results suggesting that the lack of lipid peroxidation cannot be retained anymore as a constant attribute of hepatoma cells. In fact, we studied the TBArs production in homogenates of the following hepatomas: AH-130 Yoshida , 3924 A Morris, MH1C1 hepatomas, in comparison with normal liver. Whereas we were able to confirm that TBArs production in Yoshida tumour is extremely low, we found that Morris 3924 A hepatoma, growing subcutaneously in the rat, displays a rather consistent TBArs production. Moreover, MH1C1 hepatoma, grown in cell culture, produces more TBArs than normal liver. AH-130 Yoshida tumour is unable to metabolize CC14. Consequently, the addition of CC14 to the homogenate doesn't stimulate TBArs production, as this substances does in the case of normal liver homogenate. A good increase in TBArs production was seen, however, with MH1C1 homogenate.