ADMS 3502 Lecture Notes - Lecture 20: Adenylyl Cyclase, Vascular Smooth Muscle, Protein Kinase A

• School: York University
• Department: Administrative Studies
• Course: ADMS 3502
• Professor: Cristobal Sanchez- Rodriguez

Document Summary

Alpha receptors: a1 receptors liked to gq proteins that stimulate contraction of vascular smooth muscle through ip3 signal transduction pathway. Increase in ca2: alpha 2 linked to gi proteins- decreases adenyl cycles causing the contraction of smooth muscle, beta receptors linked to gs proteins- increase camp which causes dilation, methoxamine- alpha 1 agonist, clonidine alpha 2 agonist. When blood volume in body is low, kidney"s release renin. And ras causes blood vessels to constrict: beta receptors act by adrenoreceptor-adenyly cyclase protein kinase a cascade to increase camp. Increase in camp levels induces cardiac myocyte contraction: beta 1- contraction of cardiac cells; beta 2 receptors involved in smooth muscle relaxation, bronchodilator, albuterol- beta 1 agonist, metoprolol- beta 2. Similarities b/t alpha & beta receptors: they are adrenergic receptors, both alpha & beta stimulated by epinephrine and norepinephrine. Beta receptors: vasodilation, relaxation of bronchial & uterine smooth muscles, increase hr.