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NEUROPHYSIOLOGY

Synaptic Transmission: Yisceral Efferenł Endings

■ A. Smooth musclc

B. Gland (submandibular)

■ C. Neurosecretory -(posterior piluitary)

Pituicyte processes Axon

Schwann celi cap Smooth muscle cells

Varicoslties

Terminal endings

Collagen space Basement membranę

Figurę 2.6 Viscerai Efferent Endings

Neuronal efferent endings on smooth muscle <A> and glands (B and C) exhibit unique endings unlikc the presynaptic and postsynaptic terminals observed in neuronal and ncuromuscular junction synapses. Rather, neurotransmitter substances are released into interstitial spaces <A and B) or inlo the bloodstream (C, neuroseere-tion) from expanded nerve terminal endings. This arrangement allows for the stimulation of numerous target cells over a wide area. Not all smooth muscle cells are innervated. They are connected to adjacent cells by gap junctions and can therefore contract together with the innervated cells.

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