AT1 receptors activate a large array of signal-transduction systems to produce effects that vary with cell type and that are a combination of primary and secondary responses (Figure 30-3). The relative importance of these myriad signal-transduction pathways in mediating biological responses to Angll is tissue-specific. Other receptors may alter the response to AT1-receptor activation (e.g., AT 1 receptors heterodimerize with bradykinin B2 receptors, which enhances Angll sensitivity in preeclampsia).
Signaling from AT2 receptors is mediated largely by G.. Consequences of AT2-receptor activation include activation of phosphatases, K+ channels, and bradykinin and NO production and inhibition of Ca2+ channel function.
Functions and Effects of the Renin-Angiotensin System
The renin-angiotensin system plays a major role in the regulation of arterial blood pressure. Modest increases in plasma concentrations of Angll. When a single moderate dose of Angll is injected intravenously, systemic blood pressure begins to rise within seconds, peaks rapidly, and returns to
Activation of PI3 kinase
Activation of adapter molecules
Modulation of cell cycle regulators
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Your heart pumps blood throughout your body using a network of tubing called arteries and capillaries which return the blood back to your heart via your veins. Blood pressure is the force of the blood pushing against the walls of your arteries as your heart beats.Learn more...