Nervous and Hormonal Control of Smooth Muscle Contraction Although skeletal muscle fibers are stimulated exclusively by the nervous system, smooth muscle
can be stimulated to contract by multiple types of signals: by nervous signals, by hormonal
stimulation, by stretch of the muscle, and in several other ways. The principal reason for the difference
is that the smooth muscle membrane contains many types of receptor proteins that can initiate the
contractile process. Still other receptor proteins inhibit smooth muscle contraction, which is another
difference from skeletal muscle. Therefore, in this section, we discuss nervous control of smooth
muscle contraction, followed by hormonal control and other means of control.
