Eta

Vasoconstriction

Vasodilation/vasoconstriction (ETB2)

cAMP inhibition; PLC/InsP3 calcium increase

Opioid

OP1 (delta), OP3 (mu)

Central cardiovascular regulation (OP1, 3); cardioprotection (OP1)

Gia1/3; Go

IK conductance activation; reduction in neuronal ICa; AC inhibition; PKC and KATP channel activation (cardioprotection)

AC, adenyl cyclase; ATI, AT2, angiotensin receptor 1, 2; ETA, endothelin A; ETB, endothelin B; Gi, inhibitory G protein; Gs, stimulatory G protein; Gq/11, Go, G15, other G proteins; ICa, voltage-dependent calcium channel (current); IK, voltage dependent potassium channel (current); InsP3, inositol triphosphate; KATP, potassium ATP channel; MAPK, MAP Kinase; OP1, delta-opioid receptor; OP3, mu-opioid receptor; PKC, protein kinase C; PLC, phospholipase C.

AC, adenyl cyclase; ATI, AT2, angiotensin receptor 1, 2; ETA, endothelin A; ETB, endothelin B; Gi, inhibitory G protein; Gs, stimulatory G protein; Gq/11, Go, G15, other G proteins; ICa, voltage-dependent calcium channel (current); IK, voltage dependent potassium channel (current); InsP3, inositol triphosphate; KATP, potassium ATP channel; MAPK, MAP Kinase; OP1, delta-opioid receptor; OP3, mu-opioid receptor; PKC, protein kinase C; PLC, phospholipase C.

ways characterize both p-AR (e.g., via Gs and AC) and ATI receptor signaling (e.g., via Gq/11 and PLC-p).

It was shown that selective blockade of p-AR inhibited angiotensin-induced contractility; selective blockade of ATI receptors reduced catecholamine-induced reduction in heart rate (30). These unusual transinhibitory effects were considered caused by underlying G protein-receptor uncoupling. Furthermore, direct interactions of these receptor systems were demonstrated in vivo, and it is speculated that such interactions may have a profound role in determining the ultimate responses to drugs designed to block a given receptor (e.g., pAR blockers, ATI receptor blockers). Cardiovascular receptor cross talk has been extensively reviewed by Dzimiri (31).

Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

Get My Free Ebook


Post a comment