title: Immediate mechanical reactions of isolated human detrusor muscle on x-irradiation.
abstract: The mechanical activity (isotonic registration) of isolated detrusor (smooth) muscle preparations from the human urinary bladder (surgical material) is investigated. The preparations reacted on X-irradiation (50 kV) with an immediate dose-dependent tonic contraction at threshold-doses of 100 to 1000 R (1 to 3 kR/min). The contraction was either reversible, semireversible or persistent, and the basal muscle tone was elevated. A tachyphylactic reaction was observed. The phasic activity of the preparations was temporarily increased, then inhibited after irradiation. The radiation-induced changes of the human and guinea-pig detrusor muscle are compared and their possible relation to the functional disturbances of the urinary bladder after radiotherapy is discussed.
mesh_terms: D000818:Animals; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008297:Male; D009119:Muscle Contraction; D009129:Muscle Tonus / Q000528:radiation effects; D009130:Muscle, Smooth / Q000528:radiation effects*; D011829:Radiation Dosage; D001743:Urinary Bladder / Q000528:radiation effects