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Volume 51, Issue 3
Displaying 1-12 of 12 articles from this issue
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1. Metabolic Pathways of Androgens in Rat Submaxillary GlandHideo KATSUKAWA, Takao NAKAMURA, Yuichi TANABE1980 Volume 51 Issue 3 Pages 159-164
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIt has been known that the submaxillary glands of rats and mice are androgen-sensitive. However, there are few detailed reports on the androgen metabolism by the submaxillary glands of rats and mice. The purpose of this study is to elucidate the metabolic pathways of androstenedione and testosterone in rat submaxillary glands. [4-14C] Androstenedione and [4-14C] testosterone were incubated with submaxillary gland homogenate of adult male rats in the presence of NADPH or NAD+ for 5, 15, 30, 60 and 120min. Androstenedione was converted to 5α-dihydro-testosterone and testosterone in large amounts, and 5α-androstane-3, 17-dione, androsterone and 5α-androstane-3α, 17β-diol in small amount after the incubations of 5-120min. Testosterone was converted mainly to 5α-androstane-3α, 17β-diol and, to a lesser extent, androstenedione, 5α-an-drostane-3, 17-dione, androsterone and 5α-dihydrotestosterone after the incubations of 5-120min. A mixture of [1, 2, 6, 7-3H] androstenedione and [4-14C] testosterone was incubated with submaxillary gland homogenate of adult male rats in the presence of NADPH for 5, 15, 30, 60 and 120min.3H:14C Ratios in isolated 5α-dihydrotestosterone at 5, 15, 30, 60 and 120min, divided by 3H:14C ratio of the substrates, were 0.99, 2.22, 4.38, 2.99 and 1.16. The results indicate that 5α-dihydrotesterone was produced not only by 5α-reduction of testosterone but also by 17β-reduction of 5α-androstane-3, 17-dione which was produced from androstenedione.View full abstractDownload PDF (439K) -
2. Changes in Activities of 5-Reductase and 17-Hydroxysteroid Dehydrogenase of Rat Submaxillary Gland with AgeHideo KATSUKAWA, Takao NAKAMURA, Yuichi TANABE1980 Volume 51 Issue 3 Pages 165-170
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn our previous report, the in vitro metabolism of androstenedione and testosterone by the submaxillary glands of adult male rats was demonstrated. This paper deals with the metabolism of these two androgens by the submaxillary glands of younger rats and changes of the enzymes involved in their metabolism with age. Submaxillary gland homogenates of male rats at 1, 2, 3, 4, 5, 7 and 10 weeks of age were incubated with [1, 2, 6, 7-3H] androstenenedione and [4-14C] testosterone in the presence of NADPH for 60min. Identification of metabolites was made by thin layer chromatography, derivative formation and radiorecrystallization to constant specific activity or constant 3H:14C ratio. Activity of an enzyme was expressed as the yield of the product in the reaction in which this enzyme was involved. The metabolism of androstenedione and testosterone in the submaxillary glands of these rats was largely reductive: these two androgens were rapidly converted to 5α-androstane-3, 17-dione, 5α-dihydrotesyosterone, androsterone and 5α-androstane-3α, 17β-diol. In this case, 5α-reductase and 17β-hydroxysteroid dehydrogenase were involved in these reactions. Activity of 5α-reductase, the sum of yield of 5α-androstan-3, 17-dione, 5α-dihydrotestosterone, androsterone and 5α-androstane-3α, 17β-diol from androstenedione or testosterone, decreased gradually with advancing age from 1 to 5 weeks after birth and, thereafter, increased at 7 and 10 weeks after birth. When androstenedione was used as a substrate, activity of 17β-hydroxysteroid dehydrogenase, the sum of yield of 5α-dihydrotestosterone, testosterone and 5α-androstane-3α, 17β-diol, was nealy constant in the range from l to 5 weeks after birth and became high at 7 and 10 weeks after birth. When testosterone was used as a substrate, activity of this enzyme, the sum of yield of 5α-androstane-3, 17-dione, androstenedione and androsterone, decreased with increasing age.View full abstractDownload PDF (402K) -
Masanori OKAMOTO, Yutaka TOYODA1980 Volume 51 Issue 3 Pages 171-177
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe present investigation was designed to determine the effects of glucose and pyruvate on the sperm penetration in intact and cumulus-free (denuded) mouse eggs in vitro. The basic medium used for the experiments was a chemically defined medium for the in vitro fertilization of mouse eggs (Toyoda et al., 1971), from which glucose and sodium pyruvate were omitted. Newly ovulated eggs in cumulus clot were obtained from mature females (JCL:ICR strain) treated with 10IU PMSG and 10 IU HCG 48 hr apart. In order to get denuded eggs, the intact eggs were treated with hyaluronidase solution, washed twice and then pooled. Spermatozoa were obtained from the cauda epididymidis of mature males (JCL:ICR strain), suspended into 0.4m1 medium and preincubated at 37°Cunder 5%CO2 in air for 1 hr before being mixed with the eggs. Eggs were examined for evidence of sperm penetration and fertilization 4 to 5 hr after insemination. When only pyruvate (1.0mM) was present in the medium, sperm penetration was never observed in both intact and denuded egg. By contrast, when only glucose (5.56mM) was present in the medium for sperm preincubation and fertilization, 95% of intact eggs were penetrated but only 14% of denuded eggs were penetrated. When pyruvate was present in the medium for sperm preincubation and glucose was present in the medium for fertilization, the rates of sperm penetration were very high in both intact (98%) and denuded (88%) eggs. When glucose was present in the medium for sperm preincubation and pyruvate was present in that for fertilization, the rate of sperm penetration was relatively high (64%) in intact eggs inseminated with spermatozoa prein-cubated for 1 hr, but the fertilization rate was greatly reduced when preincubation time was shortened (6-12 min) or denuded eggs were used. Sperm penetration started immediately after the introduction of glucose into the pyruvate medium containing preincubated spermatozoa and denuded eggs. The rates of sperm penetration at 1, 2, 3 and 4 hr after addition of glucose were 38, 57, 70 and 85%, respectively. These results demonstrate that glucose is needed for the sperm penetration of mouse eggs in vitro even if pyruvate, bovine serum albumin and cumulus cells are present, while pyruvate is necessary for the maintenance of the fertilizability of the gametes. It is considered that glucose acts on the final stage of sperm capacitation or on the gamete interaction during sperm penetration of zona pellucida.View full abstractDownload PDF (554K) -
Masahiko OKUBO1980 Volume 51 Issue 3 Pages 178-184
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSTo investigate milkability indices, sources of their variation and their relation to tonus of sphincter muscle of teat, Holstein cows in the herd of Hokkaido Univ. Farm were milked with bucket milker and milkability was measured with kymograph (Milk-O-Graph). Milking procedure and condition, including fore-treatment and stripping method, were constant throughout the experiment. The results obtained were as follows: 1) Maximum milk flow rate (MR), average milk flow rate (AR), milk yields in the first two and three minutes (M2m and M3m) were positively correlated to milk yield and were negatively correlated to milking time when those indices were adjusted for milk yield. Relative milk yields in the first two and three munutes expressed as a percent of total milk yield (%M2m and %M3m) were not correlated to milk yield, but were negatively correlated to milking time. Correlation between milking time and milk yield was significant only within cows. 2) Partitioning the total variance into component of cow, milking hour, interaction and within-cows, the among-cows variations in adjusted -MR, -M2m, -M3m, and unadjusted -%M2m and -%M3m were largest. Adjusted-AR had a large within-cows variation. As the index for milking time, main machine milking time-2 (T'1), the time from starting milking until flow rate dropped below 0.2kg per 30 seconds, is considered to be the most adequate, since among-cows variation in T'1 after adjusting for milk yield was large. 3) According to the relation of measures used in the present study to milking time, source of variation and measuring method, M2m, M3m, %M2m, %M3m are considered to be suitable as milkability index. 4) Tonus of sphincter muscle of teat measured by suction method was negatively correlated to MR and M2m.View full abstractDownload PDF (549K) -
Masahiko OKUBO1980 Volume 51 Issue 3 Pages 185-191
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSIn previous paper, milkability indices, source of their variation and their relation to tonus of sphincter muscle of the teat of Holstein cows measured under the constant condition were reported. The purpose of this study is to investigate milkability of Holstein cows measured under the field condition in herd of Hokkaido Univ. Farm and Niikappu Livestock Breeding Station, in which milking routine was not constant. Cows were milked with pipeline milker and milking rate was measured with weighing dish type (Milk-O-Meter) and cylinder type milk meter (MilkO-Scope and True-Test). In Nikkappu Station the teat size of cows was measured and its relation to milkability was examined. The results obtained were as follows: 1) The measured values of milkability indices were generally lower than those in previrus paper and were influenced obviously by milking routine, especially method of fore-treatment. 2) Correlations among indices were almost the same as those in previous report. Maximum milk flow rate (MR), average milk flow rate (AR), milk yield in the first two and three minutes (M2m and M3m) were positively correlated to milk yield and were negatively correlated to adjusted milking time. Relative milk yields in the first two and three minutes expressed as a percent of total milk yield (%M2m and %M3m) were not correlated to milk yield, but were negatively correlated to unadjusted milking time. Differed from previous report, correlation between milking time and milk yield was significant only among cows. 3) The percentage components of variance for measures of indices in Hokkaido Univ. Farm were almost the same as those in the previous report. In adjusted-MR, -M3m and unadjusted -%M2m and -%M3m, among-cows variations were largest. Adjusted-AR had a large within-cows variation. In Niikappu Station, among-cows variation in M3m and %M3m and within-cows variation in AR were large. Adjustment for milk yield has not changed the percentage component of variance. 4) Teat length and diameter in Niikappu Station increased with advancing lactation number and was negatively correlated to AR.View full abstractDownload PDF (527K) -
Sueo NIIMURA, Hiroyuki SASAKI, Kazuo ISHIDA1980 Volume 51 Issue 3 Pages 192-196
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSHistocheical demonstration of Δ5-3β-hydroxysteroid dehydrogenase (Δ5-3β-HSD), NADH2 dehydrogenase (NADH2-DH), NADPH2 dehydrogenase (NADPH2-DH) and glucose-6-phosphate dehydrogenase (G-6-PDH), as well as electron-histochemical demonstration of adenylate cyclase, was performed on hanster eggs in primordial through Graafian foliicles. The activity of Δ5-3β-HSD first came to appear in the eggs in large secondary follicles, getting stronger in those in Graafian follicles. The activities of NADH2-DH, NADPH2-DH and G-6-PDH first appeared in the eggs in small secondary follicles: the activities of the former two enzymes became gradually stronger along with follicular growth, while that of the last was always strong. A moderate activity of adenylate cyclase was recognised as lead granules on the cytoplasmic membrane of eggs in small secondary through Graafian follicles. These results suggest that (1) steroid synthesis starts in hamster eggs when they are in large secondary follicles, and (2) NADPH2 produced by G-6-PDH is used for steroid synthesis in the eggs.View full abstractDownload PDF (995K) -
Kazuaki TAKAHASHI, Yukio AKIBA, Tatsuro MATSUMOTO1980 Volume 51 Issue 3 Pages 197-203
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe effects of lard feeding on the carcass lipid deposition were investigated using margaric acid and lauric acid as indices of the fatty acid mobilization in 14 days old male chicks. Two kinds of experimental diet, glucose- or lard-diet, were supplemented with margaric acid and lauric acid, and were kept isocaloric and isonitrogenous. Carcass lipid deposition was markedly elevated by feeding the lard-diet. The disappearance rates of deposited lauric acid and margaric acid from the carcass lipid were not affected by feeding the lard-diet. The incorporation rate of margaric acid was increased by feeding the lard-diet and this incorporation rate fairly corresponded to the rate of increase in carcass lipid deposition. These results indicate that the increased lipid deposition after feeding of the lard-diet is attributable to the increase in direct incorporation of dietary fatty acids. It was also suggested that about 60% of carcass lipid was derived from the dietary fat in the chicks fed the lard diet (12% fat content), whereas about 90% of carcass lipid was de novo synthesized from non-fat precursors in the chicks fed the glucose-diet (2% fat content).View full abstractDownload PDF (451K) -
Mamoru SAITOH, Seiya TAKAHASHX, Kenichi KAMEOKA1980 Volume 51 Issue 3 Pages 204-214
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSNutrient requirements for the maintenance of maternal body during pregnancy of rats were examined. Total 80 of virgin female rats (about 200g body weight) of Wistar strain were used for the experiment. It was assumed that ME and DCP requirements for the maintenance corresponded to ME and DCP intakes when both energy and protein retentions were zero. ME requirement (129 kcal/day/Wkg0.76) for the maintenance of maternal body was similar to that (127 kcal/day/Wkg0.75) of non-pregnant rats. This fact shows that ME requirement for the maintenance was not affected by pregnancy. On the contrary, DCP requirement (6.91g/day/Wkg0.76) for the maintenance of maternal body was 5 times higher than that (1.30g/day/Wkg0.75) of non-pregnant rats, inn spite of positive protein retention. It was considered that DCP requirement for maintenance determined in this experiment includes a part of protein consumed for production (fetus and placenta). Therefore, it is necessary to subtract the amount of protein consumed for production from DCP requirement for maintenance determined in this experiment.View full abstractDownload PDF (578K) -
Masanori KOMATSU, Tsuneo ABE, Kou NAKAJIMA, Takao OISHI, Misao KANEMAK ...1980 Volume 51 Issue 3 Pages 215-222
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSThe potassium concentrations of red cells and the frequencies for HK gene were investigated in five cattle breeds, two goat breeds and sheep, and the properties of the HK red cell membrane were compared with those of the LK red cells. The concentrations of potassium in red cells were determined by flame photometry. In several red cell samples of cattle and goats, 50% haemolytic score, osmotic fragility and recovery rates of frozen red cells were determined on HK and LK-type red cells. The gene frequencies for HK were as follows; Japanese Black cattle: 0.138, Japanese Brown cattle: 0.190, Japanese Polled cattle: 0.239, Jersey cattle: 0.263, "Shiba" goats: 0.500, Saanen goats: 1.000. But in Holstein cattle the HK gene was absent. The average gene frequency in four breeds of sheep was 0.356. The differences of HK gene frequency were found among the five cattle breeds and the two goat breeds. HK-type red cells had a lower 50% haemolytic score and a lower recovery rate of frozen red cells than LK-type red cells in both cattle and goats. These results evidenced that there existed the difference of membrane properties between HK and LK red cells. But there was no relationship between osmotic fragility and potassium types. In respect of the association between potassium types and Ma antigen, it was shown that goat Ma antigen was a partial sheep Ma antigen and consisted of two subtypes, HK-type goat red cells were not wholly Mapositive, and HK-type cattle red cells were Ma-negative.View full abstractDownload PDF (444K) -
Hideo KATSUKAWA1980 Volume 51 Issue 3 Pages 223-225
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSDownload PDF (806K) -
Takao OISHI, Kozaburo ESAKI, Takeshi TOMITA1980 Volume 51 Issue 3 Pages 226-228
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSDownload PDF (192K) -
Tadashi KYUMA, Takeaki KIKUCHI, Masayoshi TAKAHASHI, Shizuo TAKIZAWA1980 Volume 51 Issue 3 Pages 229-232
Published: March 25, 1980
Released on J-STAGE: March 10, 2008
JOURNAL FREE ACCESSDownload PDF (260K)
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