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Autonomic Innervation of Selected Body Structures
| Structure | Sympathetic | Parasympathetic |
|---|---|---|
| eye - pupil (iris): | dilation | constrictiion |
| heart: | increased rate & force | decreased rate |
| lung bronchioles: | dilation | constriction |
| gut wall: | decreased motility | increased motility |
| gut sphincter: | constrict | relax |
| bladder detrusor: | relax | contraction |
| bladder-urethra smooth sphincter: | constrict | relax |
| penis etc.: | ejaculation | erection |
| gallbladder bile & duct: | relax | contract |
| salivary glands: | concentrated viscous saliva | abundant watery saliva |
| nasal & lacrimal glands: | vasoconstriction | abundant secretion |
| liver: | glucose production | --- |
| kidney: | renin secretion | --- |
| vessels within muscle: | dilation | --- |
| cutaneous & visceral vessels: | constriction | --- |
| piloerector muscles: | contraction | --- |
| sweat glands (cholinergic): | secretion | --- |
| adipose cells: | lipolysis | --- |
| adrenal medulla: | epinephrine secretion | --- |
NOTE: Parasympathetic postganglionic effects are produced by release of acetycholine which binds to muscarinic receptors linked to G proteins. Sympathetic postganglionic effects are produced by release of norepinephrine which binds to alpha or beta adrenergic receptors linked to G proteins. The alpha adrenergic receptors are associated with vasoconstriction and sphincter contraction. The beta adrenergic receptors are associated with smooth muscle relaxation. Some sympathetic postganglionic neurons release acetylcholine rather than norepinephirtine (e.g., those innervating sweat glands). There are multiple subtypes of all of the above receptors.