Coronary reflex
Coronary reflex is the change of coronary diameter in response to chemical, neurological or mechanical stimulation of the coronary arteries.
The coronary reflexes are stimulated differently from the rest of the vascular system.{{cn|date=March 2021}}
Causes of coronary constriction
=Chemical=
- N-nitro L-arginine
- indomethacin
- glibenclamide
- tetraethylammonium chloride
- caffeine
=Other=
- Cold
Causes of coronary dilation
Cocaine abuse frequently can cause a coronary spasm, resulting in a spontaneous myocardial infarction.{{cn|date=March 2021}}
=Chemical=
- Versed (Midazolam): a coronary dilator. In midazolam's presence, dilation was unaffected by N-nitro L-arginine, indomethacin and glibenclamide.
- Tetraethylammonium chloride, an inhibitor of the BKCa K+ channel (a high conductance Ca2+-sensitive K+ channel), dose dependently attenuated the vasodilating effect of midazolam {{cite journal | title = N-nitro L-arginine causes coronary vasoconstriction and inhibits endothelium-dependent vasodilatation in anaesthetized greyhounds|author1=O.L. Woodman |author2=G.J. Dusting | journal = Br. J. Pharmacol. | year = 1991 | volume = 103 | pages = 1407–1410 | pmid = 1909199 | issue = 2 | pmc = 1908370 | doi=10.1111/j.1476-5381.1991.tb09802.x}}
- Estrogen has been shown to abolish abnormal cold-induced coronary constriction.{{cite journal | doi = 10.1378/chest.114.6.1556 | title = Estrogen Acutely Abolishes Abnormal Cold-Induced Coronary Constriction in Men* |author1=Steven E. Reis, MD |author2=Richard Holubkov |author3=Kathleen A. Zell, BSN |author4=AJ. Conrad Smith, MD |author5=Howard A. Cohen, MD |author6=Marc D. Feldman, MD |author7=Roger S. Blumenthal, MD | journal = Chest | year = 1998 | volume = 114 | pages = 1556–1561 | pmid = 9872188 | issue = 6| doi-access = free }}