No abstract

Effects of gonadal hormones on dimorphic striated muscles such as the bulbocavernosus/levator ani complex related to male penile erection have been widely studied. However, the action of these hormones on pelvic nondimorphic muscles is not known. In the present study, the sensitivity of the male rat pubococcygeus muscle (Pcm) to gonadal hormones was studied measuring the cross-sectional area (CSA) of its fibers. For this, two experiments were done: in the first, the effect of castration, and in the second the effect of gonadal hormone administration was analyzed. We found that castration after 6 weeks significantly reduced the average CSA of the fibers of this muscle and that castration after 2 or 6 weeks reduced the percentage of fibers with higher CSAs, but only castration after 6 weeks increased the percentage of fibers with the lowest CSA. In comparison with castrated animals implanted with an empty Silastic capsule, Silastic implants of testosterone propionate or dihydrotestosterone significantly increased the average CSA of Pcm fibers, and the treatment with testosterone propionate, estradiol benzoate, or dihydrotestosterone decreased the percentage of fibers with low CSAs and increased the percentage with larger CSAs. Our results could be considered for therapy in patients with damage of the Pcm, and suffering urinary incontinence or ejaculatory dysfunctions. Anat Rec, 291:586-592, 2008. 2008 Key words: pubococcygeus muscle; dihydrotestosterone; cross-sectional area; estradiol benzoate; testosterone propionate Effects of gonadal hormones on dimorphic striated muscles related to male reproductive physiology have been studied widely, particularly the bulbocavernosus/ levator ani complex implicated in mechanisms of penile erection. It has been shown that androgens affect muscle weight (Tucek et al

Tensile properties of skin determine some important physical attributes of skin. They may be conveniently assessed using recent technologies. The aim of the study was to compare ex vivo the tensile properties of normal looking skin and striae distensae. The Cutometer was used with 2 and 4 mm diameter probes. Skin distensibility values were dependent on the suction force and area of the skin tested. Conversely, tensile ratios yielding elasticity parameters were not affected by the same variables. Although tensile properties of excised normal skin resembled those previously reported in vivo, striae distensae showed markedly different properties in vivo and ex vivo. The ex vivo and in vivo evaluations of the tensile properties and functions of skin are complementary particularly when the connective tissue is abnormal.

No abstract

No abstract