Objective: To investigate counteracting effects of intermittent -Gx exposure on changes of responsiveness of basilar artery in tall-suspended rats.
Method: Rats tail-suspended for 3 wk were daily subjected to 1 h 1.5 G or 2.6 G centrifugation, simulating -Gx exposure of various G values. Responses of perfused isolated basilar arterial rings to KCl was examined.
Result: Maximal isometric contractile response to KCl were significantly enhanced in arterial rings isolated from 3 wk tail-suspended rats as compared with that from simultaneous control rats (P < 0. 05). However, maximal isometric contractile responses to KCl of arterial rings isolated from 3 wk tail-suspended plus daily -Gx exposure rats were no difference as compared with that from simultaneous control rats, and were significantly decreased (P < 0.05) as compared with that from 3 wk tail-suspended rats.
Conclusion: Daily intermittent -Gx exposure as a countermeasure to prevent the effects of simulated weightless on changes in responsiveness of basilar artery from tail-suspended rats was valid.