Previous studies have shown that ethanol feeding to rats alters methionine metabolism by decreasing the activity of methionine synthetase. This is the enzyme that converts homocysteine in the presence of vitamin B12 and N5-methyltetrahydrofolate to methionine. The action of the ethanol results in an increase in the hepatic level of the substrate N5-methyltetrahydrofolate but as an adaptive mechanism, betaine homocysteine methyltransferase, is induced in order to maintain hepatic S-adenosylmethionine at normal levels. Continued ethanol feeding, beyond 2 months, however, produces depressed levels of hepatic S-adenosylmethionine. Because betaine homocysteine methyltransferase is induced in the livers of ethanol-fed rats, this study was conducted to determine what effect the feeding of betaine, a substrate of betaine homocysteine methyltransferase, has on methionine metabolism in control and ethanol-fed animals. Control and ethanol-fed rats were given both betaine-lacking and betaine-containing liquid diets for 4 weeks, and parameters of methionine metabolism were measured. These measurements demonstrated that betaine administration doubled the hepatic levels of S-adenosylmethionine in control animals and increased by 4-fold the levels of hepatic S-adenosylmethionine in the ethanol-fed rats. The ethanol-induced infiltration of triglycerides in the liver was also reduced by the feeding of betaine to the ethanol-fed animals. These results indicate that betaine administration has the capacity to elevate hepatic S-adenosylmethionine and to prevent the ethanol-induced fatty liver.

Abstract. Eighty-five male Han-Wistar rats were arranged into three groups: CCl 4 -exposed rats, CCl 4 ϩ betaine-exposed rats, and control rats. To see the effect of betaine alone, five rats of the control and of the CCl 4 ϩ betaine groups were sacrificed after 7 days, before exposure to CCl 4 . After that, two of the groups (the CCl 4 and CCl 4 ϩ betaine groups) were exposed to CCl 4 (1 ml/kg per day subcutaneously [SC] for 4 consecutive days), and one of the groups (control group) was given olive oil (1 ml/kg per day SC for 4 consecutive days). At the start of the study (day 0), day 1, day 2, day 3, day 4, and 3 days after the last CCl 4 and olive oil injections (day 7), samples of five rats per group were sacrificed, and the livers were taken for chemical analyses and histological examination. Oral betaine, after the acclimation period of a week, increased the number of mitochondria but not mitochondria size (day 0), compared with the case in control rats. Exposure to CCl 4 resulted in centrilobular hepatic steatosis, and the administration of betaine significantly reduced this. Morphometric analyses also revealed that the addition of betaine increased the volume density of rough endoplasmic reticulum (RER) in the perinuclear areas of liver cell cytoplasm (day 7). Additionally, the administration of betaine prevented the reduction of Golgi complexes and mitochondrial figures in the cytoplasm observed after the exposures to CCI 4 . Also, the volume density of mitochondria was smallest in the CCI 4 -group, but the difference was not statistically significant. The results indicate that oral betaine either improves recovery or reduces the toxic effects of CCl 4 on cell organelles in liver cells of male Han-Wistar rats.

Summary In a preliminary experiment, betaine was added in concentrations ranging from 0 to 3.0 percent to stallion semen diluted with 4 % glycerol extender. Motility of frozen‐thawed semen was better in the extenders with high betaine concentration than in those of low concentration or the control. In a subsequent experiment, betaine was added to extended semen from five stallions to make a 2.5 % betaine concentration. Two different cooling rates were used. The effect of betaine on spermatozoal motility was positive at both cooling rates studied. Motility of frozen‐thawed 2.5 % betaine semen samples was significantly (p < 0.001) higher than that of the control samples. Zusammenfassung Vorläufige Untersuchungen zur Verwendung von Betain als cryoprotektives Agens beim Tiefgefrieren von Hengstsamen In einer vorläufigen Untersuchung wurde 0 bis 3 % Betain dem mit 4 % Glycerin enthaltenden Extender verdünnten Hengstsamen zugefügt. Die Spermienmotilität des tiefgefrorenen und wieder aufgetauten Samens war im Extender mit hoher Betainkonzentration besser als im Extender mit niedriger Betainkonzentration oder ohne Betain. In einem weiteren Experiment wurde Betain dem verdünnten Samen von 5 Hengsten zugefügt, bis eine Betain‐Konzentration von 2,5 % erreicht war. Dabei wurden zwei verschiedene Abkühlraten verwendet. Bei beiden Abkühlraten wirkte sich diese 2,5%ige Betain‐Konzentration im Vergleich zu Kontrollbedingungen positiv auf die Spermienmotilität aus (p < 0,001).

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