Abstract
To compare actual spaceflight to ground-based simulation (hindlimb-suspension), we measured the norepinephrine (NE) content in A1, A2, A5 and A6 (locus coeruleus) and the vasopressin content in the neurohypophysial system. The experimental period was of 9 days' duration. The NE content in the locus coeruleus decreased significantly in rats flown for 9 days (67 %,p<0.001), but showed no significant changes after hindlimb-suspension. These results demonstrated that suspended rats adapted better to weightlessness-simulation than flown rats to actual microgravity. In rats flown aboard SLS-1, the vasopressin content was significantly increased in the posterior pituitary (71 %,p<0.01), and was decreased in the hypothalamus (49 %, p<0.05). In 9-day suspended rats pituitary vasopressin levels were unchanged, while in the hypothalamus a significant decrease was noted (21 %, p<0.05). It was concluded that spaceflight changes in pituitary vasopressin levels and in the locus coeruleus NE content were consistent with a stress reaction, occurring during and/or after landing. These results confirmed that hindlimb-suspension model constitutes a valid and lesstressful ground-based simulation of microgravity in rats.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call