We evaluated the effect of Tu-Chung (Eucommia ulmoides OLIV.) extract on anabolic action in castrated exercise and non-exercise rats in which the effects of male sex hormone from the testis were excluded. Castration was performed on 32 male Wistar rats aged 4 weeks. The rats were then divided into 4 groups: a non-exercise group treated with Tu-Chung extract (non Ex. Tu-chung G, n = 8), on exercise group treated with the extract (Ex. Tu-Chung G, n = 8), a non-exercise control group not treated with the extract (non Ex. Cont. G, n8), = and an untreated exercise control group (Ex. Cont. G, n=8) .
The Tu-Chung extract was administered orally at a dose of 1g/kg body weight once daily for 4 weeks. Distilled water was given by a similar method to the control groups. As the exercise load, the rats exercised on an animal treadmill at a starting speed of 20 m/min with an increase of 10 m/min every week for 30 min without rest daily for 4 weeks.
The following results were obtained:
1. The relative weight of the adrenal gland (gland weight/100 g body weight ) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and in the Ex. Tu-Chung G than in the Ex. Cont. G or the non Ex. Cont. G (p<0.001 each) .
2. The relative weight of the kidneys (kidney weight/100 g body weight) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and was slightly higher in the Ex. Tu-Chung G than in the Ex. Cont. G.
3. The relative weight of the musculus levator ani (muscle weight/100g body weight) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.001) .
4. The 17-KS level in a 24h urine sample after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G or the Ex. Tu-Chung G (p<0.001 each) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.001) .
5. The total urinary nitrogen level after 4 weeks was significantly lower in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) or the exercise group treated with the extract (p<0.05) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.05) .
These results suggest that administration of Tu-Chung extract significantly increases the relative weight of the adrenal gland, enhances androgen secretion from the reticular layer of the adrenal cortex, and promotes protein anabolic action in castrated rats. In addition, this extract appears to increase the adaptation ability of the adrenal cortex to the stress caused by exercise.

This study examined the secretion capacity of the gonadal and adrenal cortex systems and the morphology of the adrenal cortex in male rats treated with Tu-chung (Eucommia ulmoides O_LIV) extract, the main component of Tu-chung extract, geniposide, or both agents during exercise load testing.
Twenty-four 4-week-old male Wistar rats were used. The rats were divided into four groups : those treated with Tu-chung extract and geniposide (n=7), those treated with Tu-chung extract (n=6), those treated with geniposide (n=7) and a control group treated with distilled water. The dose of each agent was 0.1 ml/100g body weight. The agents were administered orally for 25 days. For the exercise load test, a treadmill for small animals was used, with a tilting angle set at 0. Exercise load testing was performed for 30 min (2-min warm up and 28-min running) daily for 25 days. The running speed was 20 m/min for the first 5 days, and then increased by 5 m/min every 5 days.
The following results were obtained.
1. The relative weight of the adrenal gland (gland weight/100 g body weight) in the group treated with Tu-chung extract and geniposide was significantly higher than that in the group treated with geniposide or the control group (p<0.01) . The relative weight of the adrenal gland in the group treated with Tu-chung extract was significantly higher than that in the group treated with geniposide or the control group (p<0.01, p<0.001) . Furthermore, the relative gland weight in the group treated with geniposide was significantly higher than that in the control group (p<0.05) .
2. In the group treated with Tu-chung extract and geniposide, the group treated with Tu-chung extract and the group treated with geniposide, the relative gland weight of the testis (testis weight/100g body weight) was significantly higher than that in the control group (p<0.001) . However, there were no significant differences among the three groups.
3. The 24-h urinary excretion of 17-ketosteroid (17-KS) in the group treated with Tu-chung extract and geniposide was significantly higher than that in the group treated with Tu-chung extract, the group treated with geniposide or the control group (p<0.01, p<0.01, p<0.001) . In the group treated with geniposide, the 24-h urinary excretion of 17-KS was significantly higher than that in the control group (p<0.05) .
4. In the three groups treated with Tu-chung extract and/or geniposide, serum testosterone levels were significantly higher than those in the control group (p<0.001, p0.05, p<0.05) .
5. Concerning the morphology of the adrenal cortex, the thickness of the reticular layer of the adrenal cortex was most markedly increased in the group treated with Tu-chung extract and geniposide, followed in order by the group treated with Tu-chung extract, the group treated with geniposide and the control group.
Administration of Tu-chung extract and the main component of Tu-chung extract, geniposide, during exercise load testing significantly increased the weights of the adrenal gland and testis, and promoted testosterone secretion in the adrenal cortex reticular layer and testis.
These findings suggest that geniposide plays an important role in the pharmacological action of Tu-chung.

We evaluated the effect of Tu-Chung (Eucommia ulmoides OLIV.) extract on anabolic action in castrated exercise and non-exercise rats in which the effects of male sex hormone from the testis were excluded. Castration was performed on 32 male Wistar rats aged 4 weeks. The rats were then divided into 4 groups: a non-exercise group treated with Tu-Chung extract (non Ex. Tu-chung G, n = 8), on exercise group treated with the extract (Ex. Tu-Chung G, n = 8), a non-exercise control group not treated with the extract (non Ex. Cont. G, n8), = and an untreated exercise control group (Ex. Cont. G, n=8) .
The Tu-Chung extract was administered orally at a dose of 1g/kg body weight once daily for 4 weeks. Distilled water was given by a similar method to the control groups. As the exercise load, the rats exercised on an animal treadmill at a starting speed of 20 m/min with an increase of 10 m/min every week for 30 min without rest daily for 4 weeks.
The following results were obtained:
1. The relative weight of the adrenal gland (gland weight/100 g body weight ) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and in the Ex. Tu-Chung G than in the Ex. Cont. G or the non Ex. Cont. G (p<0.001 each) .
2. The relative weight of the kidneys (kidney weight/100 g body weight) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and was slightly higher in the Ex. Tu-Chung G than in the Ex. Cont. G.
3. The relative weight of the musculus levator ani (muscle weight/100g body weight) after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.001) .
4. The 17-KS level in a 24h urine sample after 4 weeks was significantly higher in the non Ex. Tu-Chung G than in the non Ex. Cont. G or the Ex. Tu-Chung G (p<0.001 each) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.001) .
5. The total urinary nitrogen level after 4 weeks was significantly lower in the non Ex. Tu-Chung G than in the non Ex. Cont. G (p<0.001) or the exercise group treated with the extract (p<0.05) and also in the Ex. Tu-Chung G than in the Ex. Cont. G (p<0.05) .
These results suggest that administration of Tu-Chung extract significantly increases the relative weight of the adrenal gland, enhances androgen secretion from the reticular layer of the adrenal cortex, and promotes protein anabolic action in castrated rats. In addition, this extract appears to increase the adaptation ability of the adrenal cortex to the stress caused by exercise.

Allantoin is one of the oxidation products of uric acid resulting from attack by oxygen free radicals. In this study we attempted to clarify the antioxidant effect of uric acid during exercise, and the influence of other antioxidants on urate in vitro. Seven healthy male subjects performed exhaustive (100%VO_2max) and mild endurance (40%VO_2max) cycling exercise, and serum uric acid and allantoin were measured before and up to 24 h after the exercise. Various radicals were added to uric acid, ascorbic acid and glutathione were mixed with phosphate buffer or fresh human serum, and changes in each of the antioxidants (protein sulfhydryl groups in serum were measured instead of glutathione in buffer) and allantoin were examined. The serum allantoin level increased immediately after exhaustive exercise and remained high for up to 2 h, while uric acid increased at 0.5 h and remained at a high level at 24 h during recovery. On the other hand, no significant changes in allantoin and uric acid were observed after mild endurance exercise. Superoxide anion radicals (O₂^-) generated by a hypoxanthine-xanthine oxidase (HX-XOD) system formed allantoin with decreasing levels of other antioxidants in buffer and serum, although uric acid was generated by this system. To determine the influence of uric acid newly produced by the HX-XOD system, different kind of antioxidants in buffer were used to examine allantoin generation. Allantoin was generated in the order uric acid only>no antioxidants>three kinds of antioxidants during 20 min of reaction. Hydroxyl radicals (·OH) generated by the Fenton reaction also formed allantoin as other antioxidants decreased, while hydrogen peroxide did not oxidize uric acid to allantoin despite the fact that other antioxidants were consumed in the buffer and serum. These results suggest that O₂^- and ·OH oxidize uric acid to allantoin during exhaustive exercise, whereas, ascorbic acid, glutathione and protein sulfhydryl groups inhibit allantoin generation. Moreover, uric acid previously present in the body may be used for radical scavenging more effectively than that newly generated by exhaustive exercise.

The purpose of this research was to study the effects of Tu-Chung extract (Eucommia ulmoides OLIV.) administration on serum testosterone and the possible mechanisms in hindlimb- suspended rats. 25 five-week old male Wistar rats were used. All rats were randomly divided into two groups : those treated with Tu-Chung extract (Tu-Chung G, n=suspended for 37 days in hindlimb. 1 mg/ml Tu-Chung extract was administered orally once daily at a dose of 1 ml/100 g body weight. Distilled water was administered in a similar way to the control group. The following results were observed :
1. Serum testosterone concentration in Tu-Chung G was significantly higher than in Cont. G (P<0.001) .
2. There was no significant difference between Tu-Chung G and Cont. G in serum LB concentrations.
3. The Testicular cAMP level in Tu-Chung G was significantly higher than that in Cont. G (P<0.01) .
4. 24-h urinary excretion of 17-ketosteroid in Tu-Chung G was significantly higher than that in Cont. G (P<0.001) .
5. There were no significant differences between the two groups in the weights per body weight of the kidneys, adrenal grand and testes. These results suggest that the adininstration of Tu-Chung extract inducing high serum testosterone concentrations in hindlimb-suspended rats might be due to enhanced testicular and adrenal functions, not pituitary.