BIOLOGY 3U03 Chapter Notes - Chapter 4: Angiotensin-Converting Enzyme, Cerebral Cortex, Vascular Resistance

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 3U03
• Professor: Michael O' Donnell

Document Summary

Circulatory control mechanisms (ch 15, 16, 17, 18 & 19) Active controls on blood vessel radius: nerves. Generally important in overall, rather than local, distribution of blood flow. Innervates -adrenergic receptors in arteries & arterioles of most tissues especially kidney, gut, spleen, skin and all veins. Innervates 2-adrenergic re(cid:272)eptors of arteries & arterioles i(cid:374) a fe(cid:449) (cid:862)(cid:272)riti(cid:272)al(cid:863) tissues. Innervates -adrenergic constrictor receptors, 2-adrenergic dilatory receptors & Muscarinic cholinergic dilatory receptors in arterioles of various skeletal muscles. Parasympathetic nervous system: negligible role in controlling blood vessel radius, except for muscarinic cholinergic vasodilation of erectile tissue. Sympathetic vasomotor nerve fibers: leave spinal cord through all the thoracic spinal nerves and. 1st one or two lumbar spinal nerves: then to sympathetic chain, then to: heart or viscera/peripheral blood vessels. Overall influence of sns on most blood vessels is vasoconsrictory. I(cid:374)(cid:272)reased n (cid:862)to(cid:374)e(cid:863) increases trp/map: de(cid:272)reased n (cid:862)to(cid:374)e decreases trp/map. In most tissues, all the vessels except the capillaries are innervated: hormones.