Fiber type characterization of striated muscles related to micturition in female rabbits.
Pelvic and perineal striated muscles are relevant for reproduction and micturition in female mammals. Damage to these muscles is associated with pelvic organ prolapse and stress urinary incontinence. The fiber type composition of skeletal muscle influences the susceptibility for damage and/or regeneration. The aim of the present study was to determine the fiber type composition of a perineal muscle, the bulbospongiosus, and a pelvic muscle, the pubococcygeus. Both muscles were harvested from adult female rabbits (8-10 months old). NADH-TR (nicotinamide adenine dinucleotide tetrazolium reductase) histochemistry was undertaken to identify oxidative and glycolytic muscle fibers. Alkaline (pH 9.4) ATP-ase (actomyosin adenosine triphosphatase) histochemistry was used to classify type I, type IIb or type IIa/IId muscle fibers. Results showed that the content of glycolytic fibers in the bulbospongiosus muscle was higher than that of oxidative fibers. Meanwhile, the opposite was true for the pubococcygeus. In the bulbospongiosus muscle, the content of type IIb muscle fibers was higher than that of type I, but was similar to that of type IIa/IId. In contrast, the content of each fiber type was similar in the pubococcygeus muscle. The relative proportion of fibers in bulbospongiosus and pubococcygeus muscles is consistent with their function during voiding and storage phases of micturition.
Centro Tlaxcala de Biología de la Conducta, Universidad Autonóma de Tlaxcala, Carr. Fed. Tlaxcala-Puebla km 1.5 s/n, 90070 Tlaxcala, Tlaxcala, Mexico; Doctorado en Neuroetología, Universidad Veracruzana, Av. Dr. Luis Castelazo s/n, 91190 Xalapa, Veracruz, Mexico.
Kenia
K
López-García
Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco, Del. Gustavo A. Madero, C.P., 07360 México, D.F., Mexico.
Silvia
S
Mariscal-Tovar
Centro Tlaxcala de Biología de la Conducta, Universidad Autonóma de Tlaxcala, Carr. Fed. Tlaxcala-Puebla km 1.5 s/n, 90070 Tlaxcala, Tlaxcala, Mexico; Departamento de Biología Celular y Fisiología, Unidad Periférica Tlaxcala, Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Carr. Fed. Tlaxcala-Puebla km 1.5 s/n, 90070 Tlaxcala, Tlaxcala, Mexico.
Margarita
M
Martínez-Gómez
Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional, Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco, Del. Gustavo A. Madero, C.P., 07360 México, D.F., Mexico.
Ismael
I
Jiménez-Estrada
Centro Tlaxcala de Biología de la Conducta, Universidad Autonóma de Tlaxcala, Carr. Fed. Tlaxcala-Puebla km 1.5 s/n, 90070 Tlaxcala, Tlaxcala, Mexico. Electronic address: fcocastelan@uatx.mx.
Francisco
F
Castelán
D000009:Abdominal Muscles / Q000166:cytology*; D000818:Animals; D005260:Female; D018485:Muscle Fibers, Skeletal / Q000166:cytology*; D011817:Rabbits; D014554:Urination
Fiber type; Muscle ATPase; NADH-TR; Pelvic floor; Perineum; Rabbit