Smooth muscle pacemaker potential

A pacemaker potential involves gradual depolarization of the cell membrane to threshold. The subsequent generation of an action potential causes smooth muscle contraction. This type of spontaneous depolarization is referred to as a "pacemaker potential" because it creates a regular rhythm of contraction. 

Another principal means of action potential generation consists in spontaneous, rhythmic membrane depolarization. This occurs in specialized pacemaker cells in heart and smooth muscle. Therefore, while these tissues are modulated by neuronal and hormonal influences, they are capable of self-stimulation in the absence of any neuronal control. 

Four types of calcium channels, differing in location and function, have been identified (a) L type, located in skeletal, cardiac, and smooth muscles, causing contraction of mascle cells (bt T type, found in pacemaker cells, caasing Ca entry, inactivated at more negative potentials and more rapidly than the L type (c) N type, found in neurons and acting in transmitter release and (d) P type, located in Purkinje cells but whose function is unknown at this lime. 

Smooth muscle Slow wave potential changes Pacemaker activity for Myogenic rhythm... 

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