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M. V. L. BENNETT
scopic examination reveals that the innervation is very dense (Fig. 10).
The organ discharges of a large Torpedo are monophasic pulses, positive
on the dorsal surface and about 5 msec in duration and SO V in amplitude recorded in air (Bennett et al., 1961). The internal resistance of
the organs is low, and the power output at the peak of the pulses can
exceed 1 kW.
Because the electrocytes of Torpedo are very thin, it is difficult to
use two or more electrodes for differential recording across the two
faces and the entire cell. However, a single electrode can be advanced
into a column of cells, and successive changes in resting potential and
response can be used to determine electrode position as described in
Fig. 10. Fine structure of torpedinid electrocytes ( Torpedo murmorutu). The
central portion of the figure shows a perpendicular section through three electrocytes ( E P ) , dorsal surface upwards. The ventral surface is densely covered with
nerve endings ( n ) . On the left is shown a region of the uninnervated surface at
higher magnification. Several external openings of the many canaliculi are seen ( A ? ) .
The rectangles (Bt) indicate branch points of the canaliculi. Basement membrane
material extends deeply into the canalicular network. On the right is shown a
higher magnification of the innervated surface. Nerve profiles contain vesicles ( v )
as well as small granules ( g ) , possibly glycogen, and lie embedded in the electrocyte. Occasion folds ( j ) extend quite deeply into the postsynaptic cell. From
Sheridan et al. (1966).
M. V. L. BENNETT
scopic examination reveals that the innervation is very dense (Fig. 10).
The organ discharges of a large Torpedo are monophasic pulses, positive
on the dorsal surface and about 5 msec in duration and SO V in amplitude recorded in air (Bennett et al., 1961). The internal resistance of
the organs is low, and the power output at the peak of the pulses can
exceed 1 kW.
Because the electrocytes of Torpedo are very thin, it is difficult to
use two or more electrodes for differential recording across the two
faces and the entire cell. However, a single electrode can be advanced
into a column of cells, and successive changes in resting potential and
response can be used to determine electrode position as described in
Fig. 10. Fine structure of torpedinid electrocytes ( Torpedo murmorutu). The
central portion of the figure shows a perpendicular section through three electrocytes ( E P ) , dorsal surface upwards. The ventral surface is densely covered with
nerve endings ( n ) . On the left is shown a region of the uninnervated surface at
higher magnification. Several external openings of the many canaliculi are seen ( A ? ) .
The rectangles (Bt) indicate branch points of the canaliculi. Basement membrane
material extends deeply into the canalicular network. On the right is shown a
higher magnification of the innervated surface. Nerve profiles contain vesicles ( v )
as well as small granules ( g ) , possibly glycogen, and lie embedded in the electrocyte. Occasion folds ( j ) extend quite deeply into the postsynaptic cell. From
Sheridan et al. (1966).