Vascular responsiveness to various vasoactive substances after exchange transfusion with pyridoxalated hemoglobin polyoxyethylene conjugate (PHP) solution in anesthetized rats.
Vascular responsiveness to various vasoactive substances after exchange transfusion with a modified hemoglobin (pyridoxalated hemoglobin polyxyethylene conjugate; PHP) was examined in anesthetized rats. The hindlimb region of the rat was perfused through the abdominal aorta with autologous blood at a constant flow rate, using a perfusion pump. Perfusion pressure (PP), systemic blood pressure (SBP), and heart rate were measured. Exchange transfusion with a 6% PHP solution (20 ml/kg) was performed and effects of intra-arterial injections of norepinephrine (NE), angiotensin-II (A-II), serotonin (5-HT), acetylcholine (ACh), and nitroglycerin (NG) on PP and SBP were examined. The NE and A-II induced a dose-dependent increase in PP, while ACh and NG induced a decrease in PP. There was no difference in vascular responsiveness to ACh, NG, A-II, and 5-HT before and after exchange transfusion with PHP solution, but NE-induced responses were augmented after exchange transfusion with PHP. Results suggest that the presence of PHP moiety in circulation would not alter vascular responsiveness to ACh, NG, A-II, and 5-HT in a significant manner.
Kida
Y
Y
Life Science Laboratories, Ajinomoto Co., Inc., Yokohama, Japan.
Iwata
S
S
Gyoutoku
Y
Y
Aikou
A
A
Yamakawa
T
T
Nishi
K
K
D000768:Anesthesia, General; D000818:Animals; D001802:Blood Substitutes / Q000494:pharmacology*; D006454:Hemoglobins / Q000494:pharmacology*; D006614:Hindlimb / Q000098:blood supply; D008297:Male; D010477:Perfusion; D011092:Polyethylene Glycols / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014655:Vascular Resistance / Q000187:drug effects*; D014662:Vasoconstrictor Agents / Q000494:pharmacology*; D014665:Vasodilator Agents / Q000494:pharmacology*
D001802:Blood Substitutes; D006454:Hemoglobins; D014662:Vasoconstrictor Agents; D014665:Vasodilator Agents; C050907:pyridoxalated-hemoglobin-polyethylene glycol conjugate; D011092:Polyethylene Glycols