Effects of oral administration of chlormadinone acetate on canine prostatic hypertrophy.

Seven of the 25 dogs (4 to 15 years old) with benign prostatic hypertrophy (BPH) at the teaching hospital of Nippon Veterinary and Animal Science University from 1989 through 1990 were treated orally with chlormadinone acetate (CMA), a synthetic anti-androgen, 2 mg/kg/day, twice a day for 3 or 4 weeks. Prostatic size was measured by radiography and ultrasonography before and after CMA treatment, and prostatic volume was calculated from the images. Semen quality was examined in 3 of the dogs with BPH. Peripheral blood samples were collected and plasma levels of LH, 4-androstenedione, 5 alpha-dihydrotestosterone, testosterone and estradiol-17 beta were measured. Clinical signs disappeared within 10 days after the start of CMA treatment. The mean (+/- S.E.) prostatic volume 3 or 4 weeks after treatment decreased to 39 +/- 4% of the pretreatment volume. The mean level of plasma testosterone in the dogs with BPH before treatment was significantly lower than that in the normal dogs (P < 0.01). In 6 of the CMA-treated dogs the levels of all hormones examined, except LH, were significantly lower after CMA treatment than before (P < 0.05). The sperm count and motility decreased and the percentage of abnormal sperms increased after CMA treatment. These results demonstrate that, although CMA treatment in dogs with BPH inhibits testicular function, the prostatic volume is markedly reduced and clinical signs disappear in a short period after the therapy. However, a relapse of BPH was observed approximately 6 months after oral CMA treatment in some dogs.

Vitamin C administration attenuates overload-induced skeletal muscle hypertrophy in rats.

AIM: This study aimed to investigate the effects of vitamin C administration on skeletal muscle hypertrophy induced by mechanical overload in rats. METHODS: Male Wistar rats were randomly assigned to three groups: (i) sham-operated group (n = 8), (ii) placebo-administered group (n = 8) and (iii) vitamin C-administered group (n = 8). In the placebo-administered and vitamin C-administered groups, the gastrocnemius and soleus muscles of the right hindlimb were surgically removed to overload the plantaris muscle. Vitamin C (500 mg kg(-1)) was orally administered to the vitamin C-administered group once a day for 14 days. RESULTS: Synergist muscle ablation caused significant increases in wet weight and protein concentration of the plantaris muscle in both the placebo-administered (P < 0.01) and vitamin C-administered groups (P < 0.01) compared with the sham-operated group (SHA). However, the magnitude of plantaris muscle hypertrophy (expressed as a percentage of the contralateral plantaris muscle) was significantly smaller (P < 0.01) in the vitamin C-administered group (141%) than in the placebo-administered group (PLA) (152%). Compared with the SHA, only the PLA showed higher expressions of phosphorylated p70s6k and Erk1/2 (positive regulators of muscle protein synthesis) and a lower expression of atrogin-1 (a muscle atrophy marker). Concentrations of vitamin C and oxidative stress markers in the overloaded muscle were similar between the placebo-administered and vitamin C-administered groups. CONCLUSION: Oral vitamin C administration can attenuate overload-induced skeletal muscle hypertrophy, which may have implications for antioxidant supplementation during exercise training.