These results demonstrate that depending on the tissue and the experimental conditions, vasoconstrictor and vasodilator factors possess dilator or constrictor properties, and can hyperpolarize
or depolarize vascular smooth muscle cells (VSMCs) (28, 44).
Activation of the receptor can hyperpolarize
neurons through the influx of negative charges at membrane potentials below the threshold for action potential generation.
Since acetylcholine did not hyperpolarize
the LC neurons (181), it was proposed (186) that the actual inhibition of REM-OFF neurons in the LC might be caused by an inhibitory neurotransmitter, which might be triggered by acetylcholine, leading to the generation and regulation of REM sleep.
During an action potential, the plasma membrane depolarizes to approximately 0 V and the vacuolar membrane hyperpolarizes
to approximately -0.050 V.
In contrast, the rods and cones of vertebrates respond to light via c-opsins that interact with [G[alpha].sub.i] proteins and hyperpolarize
in response to light through the closing of leaky Na+ channels (Fain et al., 2010).
Opening of sarc[K.sub.ATP] channels produced by hypoxia, ischemia, or pharmacological [K.sub.ATP] openers would hyperpolarize
cell membrane, shorten action potential duration, inhibit calcium influx, and finally lead to a cardioprotective effect by depression of contractility [11-13].
DISCUSSION: Retina acts as a transducer to convert light energy to neuronal signals and which is directly propotinal to illuminance Light sensitive photo receptors cones hyperpolarize
in response to light and these cells translate the visual image impinging upon the retina into continuous action potentials which propagates along the optic pathway to the visual centers within the brain.
Hair cells in back of the centrifugal force vector hyperpolarize
in response to rotation.
Nodal cells spontaneously depolarize ("pace'), and activation of the adenosine Al receptor triggers outward [K.sup.+] currents that hyperpolarize
the nodal cell and oppose pacing.
Its effect on the muscle potential is inhibitory-that is, it produces ionic permeability changes that hyperpolarize
the muscle membrane and move its excitability away from the threshold for contraction , thereby modifying the nature of the contraction produced by exciter activity.
At temperatures greater than 15[degrees]C, May axons become progressively more depolarized, while August axons continue to hyperpolarize
until approximately 20[degrees]C, after which they level out.