1. The effect of capsaicin on bladder motility in vivo (urethane anaesthesia) and in vitro, plasma extravasation (Evans blue leakage technique) and content of substance P-like immunoreactivity (SP-LI) of the urinary bladder was investigated in various mammalian species. 2. Systemic capsaicin desensitization (rat and hamster, 50 mg/kg s.c. 4 days before; guinea-pig 55 mg/kg s. c. 4-7 days before) increased bladder capacity in rats and guinea-pigs and reduced voiding efficiency in guinea-pigs. All other urodynamic parameters were unaffected in both rats, guinea-pigs and hamsters. 3. Reflex bladder voiding was abolished by spinal cord transection in anaesthetized rats and hamsters. On the other hand, hexamethonium-(20 mg/kg i.v.)sensitive voiding contractions were obtained in response to saline filling 45 min from cord transection in guinea-pigs, indicating a profound interspecies variation in the basic organization of micturition. 4. Exposure to capsaicin (1 μM) produced a contraction of...
Species-related variations in the effects of capsaicin on urinary bladder functions: relation to bladder content of substance P-like immunoreactivity
ABELLI, Luigi;
1987
Abstract
1. The effect of capsaicin on bladder motility in vivo (urethane anaesthesia) and in vitro, plasma extravasation (Evans blue leakage technique) and content of substance P-like immunoreactivity (SP-LI) of the urinary bladder was investigated in various mammalian species. 2. Systemic capsaicin desensitization (rat and hamster, 50 mg/kg s.c. 4 days before; guinea-pig 55 mg/kg s. c. 4-7 days before) increased bladder capacity in rats and guinea-pigs and reduced voiding efficiency in guinea-pigs. All other urodynamic parameters were unaffected in both rats, guinea-pigs and hamsters. 3. Reflex bladder voiding was abolished by spinal cord transection in anaesthetized rats and hamsters. On the other hand, hexamethonium-(20 mg/kg i.v.)sensitive voiding contractions were obtained in response to saline filling 45 min from cord transection in guinea-pigs, indicating a profound interspecies variation in the basic organization of micturition. 4. Exposure to capsaicin (1 μM) produced a contraction of...I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


