Blood pressure and mesenteric resistance arterial function after spaceflight.
Ground studies indicate that spaceflight may diminish vascular contraction. To examine that possibility, vascular function was measured in spontaneously hypertensive rats immediately after an 18-day shuttle flight. Isolated mesenteric resistance arterial responses to cumulative additions of norepinephrine, acetylcholine, and sodium nitroprusside were measured using wire myography within 17 h of landing. After flight, maximal contraction to norepinephrine was attenuated (P < 0.001) as was relaxation to acetylcholine (P < 0.001) and sodium nitroprusside (P < 0.05). At high concentrations, acetylcholine caused vascular contraction in vessels from flight animals but not in vessels from vivarium control animals (P < 0.05). The results are consistent with data from ground studies and indicate that spaceflight causes both endothelial-dependent and endothelial-independent alterations in vascular function. The resulting decrement in vascular function may contribute to orthostatic intolerance after spaceflight.
Hatton
Daniel C
DC
Department of Nephrology, Hypertension, and Clinical Pharmacology, Oregon Health Sciences University, Portland, Oregon 97201, USA. hattond@ohsu.edu
Yue
Qi
Q
Chapman
Justin
J
Xue
Hong
H
Dierickx
Jacqueline
J
Roullet
Chantal
C
Coste
Sarah
S
Roullet
Jean Baptiste
JB
McCarron
David A
DA
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001794:Blood Pressure / Q000502:physiology*; D008297:Male; D008638:Mesenteric Arteries / Q000033:anatomy & histology / Q000502:physiology*; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects; D009599:Nitroprusside / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR; D013026:Space Flight; D013152:Splanchnic Circulation / Q000502:physiology*; D014655:Vascular Resistance / Q000502:physiology*; D014665:Vasodilator Agents / Q000494:pharmacology
D014665:Vasodilator Agents; D009599:Nitroprusside; D000109:Acetylcholine