TY - JOUR
T1 - Enhanced coronary vasoconstriction in the syrian myopathic hamster supports the microvascular spasm hypothesis
AU - Conway, Robert S.
AU - Natelson, Benjamin H.
AU - Chen, Wen Hwei
AU - Ting, Windsor
N1 - Funding Information:
This research was funded by a grant-in-aid from the American Heart Association, New Jersey Affiliate. The authors would like to thank Pat Moore for her help in preparing this manuscript.
PY - 1994/3
Y1 - 1994/3
N2 - Objective: The heart of the young Syrian cardiomyopathic hamster (CMH) displays discrete patches of active myocytolytic necrosis and it has been hypothesised that these lesions are triggered by arteriolar spasm. Accordingly, we tested the theory that the coronary vasoconstrictor response to arginine vasopressin (AVP) infusion is more vigorous in the actively necrotising young (2-3 month old) CMH than in age matched normal hamsters, 5-6 month old CMHs in the histologically quiescent phase of the disease, or 5-6 month old normal hamsters. Methods: An isovolumetric isolated heart preparation was used in which the coronary arteries were perfused with Krebs-Henseleit buffer at constant flow by a syringe pump. Coronary vascular resistance was determined by the ratio of measured perfusion pressure to flow rate during extended diastoles. Results: There were no significant differences in baseline coronary vascular resistance among the four groups. The increase in resistance with AVP infusion (0.54 pressor units·min-1) was significantly greater (p < 0.01) in the young CMH [6.66(SEM 4.75) mm Hg·ml-1·min-1] than in the old CMH [1.66(0.78)], the young normal [1.10(1.07)], and the old normal [2.72(1.86)] groups. Conclusions: There is increased vasoconstrictive responsiveness in the young CMH coronary vasculature. The results suggest a broader coronary abnormality in this myopathic model and are consistent with the microvascular spasm hypothesis of myocytolytic lesion formation.Cardiovascular Research 1994;28:320-324.
AB - Objective: The heart of the young Syrian cardiomyopathic hamster (CMH) displays discrete patches of active myocytolytic necrosis and it has been hypothesised that these lesions are triggered by arteriolar spasm. Accordingly, we tested the theory that the coronary vasoconstrictor response to arginine vasopressin (AVP) infusion is more vigorous in the actively necrotising young (2-3 month old) CMH than in age matched normal hamsters, 5-6 month old CMHs in the histologically quiescent phase of the disease, or 5-6 month old normal hamsters. Methods: An isovolumetric isolated heart preparation was used in which the coronary arteries were perfused with Krebs-Henseleit buffer at constant flow by a syringe pump. Coronary vascular resistance was determined by the ratio of measured perfusion pressure to flow rate during extended diastoles. Results: There were no significant differences in baseline coronary vascular resistance among the four groups. The increase in resistance with AVP infusion (0.54 pressor units·min-1) was significantly greater (p < 0.01) in the young CMH [6.66(SEM 4.75) mm Hg·ml-1·min-1] than in the old CMH [1.66(0.78)], the young normal [1.10(1.07)], and the old normal [2.72(1.86)] groups. Conclusions: There is increased vasoconstrictive responsiveness in the young CMH coronary vasculature. The results suggest a broader coronary abnormality in this myopathic model and are consistent with the microvascular spasm hypothesis of myocytolytic lesion formation.Cardiovascular Research 1994;28:320-324.
KW - Arginine vasopressin
KW - Coronary vasoconstriction
KW - Micro-vascular spasm
UR - http://www.scopus.com/inward/record.url?scp=85047678259&partnerID=8YFLogxK
U2 - 10.1093/cvr/28.3.320
DO - 10.1093/cvr/28.3.320
M3 - Article
C2 - 8174151
AN - SCOPUS:85047678259
SN - 0008-6363
VL - 28
SP - 320
EP - 324
JO - Cardiovascular Research
JF - Cardiovascular Research
IS - 3
ER -