Figure Q10-23 shows an example of endocannabinoid modulation of synaptic strength after high frequency stimulation (indicated by the horizontal bar above the large amplitude activity) to the presynaptic CA3 neurons. What would happen to the response if the CB1 receptors were blocked? Figure Q10-23
A) The frequency of spontaneous IPSPs immediately after the stimulus would decrease compared to their frequency prior to the stimulation.
B) The frequency of spontaneous IPSPs immediately after the stimulus would increase compared to their frequency prior to the stimulation.
C) The frequency of the spontaneous IPSPs would not change immediately after the stimulus compared to the frequency of spontaneous IPSPs prior to the stimulation.
D) The amplitude of the spontaneous IPSPs would increase immediately after the stimulus, compared to their amplitude prior to the stimulation.
E) The amplitude of the spontaneous IPSPs would decrease immediately after the stimulus, compared to their amplitude prior to the stimulation.

Question

Figure Q10-23 shows an example of endocannabinoid modulation of synaptic strength after high frequency stimulation (indicated by the horizontal bar above the large amplitude activity) to the presynaptic CA3 neurons. What would happen to the response if the CB1 receptors were blocked?  Figure Q10-23
A) The frequency of spontaneous IPSPs immediately after the stimulus would decrease compared to their frequency prior to the stimulation. 
B) The frequency of spontaneous IPSPs immediately after the stimulus would increase compared to their frequency prior to the stimulation. 
C) The frequency of the spontaneous IPSPs would not change immediately after the stimulus compared to the frequency of spontaneous IPSPs prior to the stimulation. 
D) The amplitude of the spontaneous IPSPs would increase immediately after the stimulus, compared to their amplitude prior to the stimulation. 
E) The amplitude of the spontaneous IPSPs would decrease immediately after the stimulus, compared to their amplitude prior to the stimulation.

Quizplus · Accepted Answer

If the endocannabinoid receptors are blocked, the retrograde signal would be blocked and therefore the depolarization-induced suppression of the presynaptic inhibition would be removed. This would result in a lack of change of spontaneous transmitter release in the presynaptic neuron.

Figure Q10-23 Shows an Example of Endocannabinoid Modulation of Synaptic