FRINK Linked Data Fragments server

Matches in SemOpenAlex for { <https://semopenalex.org/work/W4301934688> ?p ?o ?g. }

• W4301934688 abstract "Article Figures and data Abstract Editor's evaluation Introduction Results Discussion Materials and methods Data availability References Decision letter Author response Article and author information Metrics Abstract In the striatum, acetylcholine (ACh) neuron activity is modulated co-incident with dopamine (DA) release in response to unpredicted rewards and reward-predicting cues and both neuromodulators are thought to regulate each other. While this co-regulation has been studied using stimulation studies, the existence of this mutual regulation in vivo during natural behavior is still largely unexplored. One long-standing controversy has been whether striatal DA is responsible for the induction of the cholinergic pause or whether DA D2 receptors (D2Rs) modulate a pause that is induced by other mechanisms. Here, we used genetically encoded sensors in combination with pharmacological and genetic inactivation of D2Rs from cholinergic interneurons (CINs) to simultaneously measure ACh and DA levels after CIN D2R inactivation in mice. We found that CIN D2Rs are not necessary for the initiation of cue-induced decrease in ACh levels. Rather, they prolong the duration of the decrease and inhibit ACh rebound levels. Notably, the change in cue-evoked ACh levels is not associated with altered cue-evoked DA release. Moreover, D2R inactivation strongly decreased the temporal correlation between DA and ACh signals not only at cue presentation but also during the intertrial interval pointing to a general mechanism by which D2Rs coordinate both signals. At the behavioral level D2R antagonism increased the latency to lever press, which was not observed in CIN-selective D2R knock out mice. Press latency correlated with the cue-evoked decrease in ACh levels and artificial inhibition of CINs revealed that longer inhibition shortens the latency to press compared to shorter inhibition. This supports a role of the ACh signal and it’s regulation by D2Rs in the motivation to initiate actions. Editor's evaluation The study addressed interactions between two key striatal transmitters dopamine and acetylcholine during an appetitive behavioral task. Helping to reconcile conflicting evidence in the literature, the data show that changes in both transmitters are correlated and that decreases in acetylcholine with reward and reward cues are only partially a consequence of elevated dopamine release acting at D2 dopamine receptors on striatal cholinergic interneurons. This manuscript will be of interest to those interested in the neural correlates of appetitive behavior and dopamine and striatal function. https://doi.org/10.7554/eLife.76111.sa0 Decision letter Reviews on Sciety eLife's review process Introduction Dopamine (DA) plays a key role in learning, serving as a teaching signal that reflects reward prediction error (Day et al., 2007; Mohebi et al., 2019; Nasser et al., 2017; Schultz et al., 1997; Steinberg et al., 2013). This teaching function is encoded in the phasic bursting of DA neurons, which induces a rapid but transient increase of extracellular DA. DA is initially released in response to an unpredicted reward, but with learning the response shifts away from the reward outcome toward reward-predicting cues (Schultz, 2007; Schultz et al., 1997). Like DA neurons, cholinergic interneurons (CINs) in rodents and their presumed counterparts, ‘tonically active neurons’ (TANs), in primates modulate their activity in response to reward-predicting cues and salient outcomes. CINs represent about 1–2% of the neurons in the striatum and regulate mental processes including reinforcement learning, action selection, associative learning, and cognitive flexibility (Aoki et al., 2015; Bradfield et al., 2013; Joshua et al., 2008; Matamales et al., 2016; Maurice et al., 2015; Morris et al., 2004; Okada et al., 2014). Pharmacogenetic inhibition of CINs in the nucleus accumbens (NAc) also increases the influence of appetitive cues on instrumental actions pointing to a role of striatal acetylcholine (ACh) in motivation (Collins et al., 2019). CINs are tonically active and show a multiphasic response to salient and conditioned stimuli that can include a short excitation followed by a prominent pause and rebound excitation (Aosaki et al., 1994a; Aosaki et al., 1994b; Apicella, 2007; Apicella et al., 2009; Apicella et al., 2011). This multiphasic response in CIN firing coincides with phasic activation of midbrain DA neurons that terminate in the striatum (Joshua et al., 2008; Morris et al., 2004; Schultz, 2007; Schultz et al., 1997). Furthermore, there is increasing evidence that DA and ACh regulate each other within the striatum (Cachope and Cheer, 2014; Cachope et al., 2012; Chuhma et al., 2014; Cragg, 2006; Helseth et al., 2021; Kharkwal et al., 2016; Straub et al., 2014; Sulzer et al., 2016; Threlfell et al., 2012; Yan and Surmeier, 1991). Here, we will focus on the DA regulation of the multiphasic ACh response. One long-standing discussion in this regard has been whether the cholinergic pause is dependent on DA via DA D2R receptor (D2R) mediated inhibition of CINs. Early evidence that the CIN pause is DA-dependent originate from studies in non-human primates (NHPs). In vivo electrophysiological recordings from TANs have revealed a pronounced pause in firing to a reward-predicting stimulus. This pause was entirely abolished by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine lesions of DA neurons and local administration of a D2R antagonist (Aosaki et al., 1994b; Watanabe and Kimura, 1998). Consistent with this, more recent slice physiology studies in rodents have shown that pauses in CIN activity can be induced by local application of DA or DA terminal stimulation, in which both are eliminated by pharmacological blockade of D2Rs (Augustin et al., 2018; Chuhma et al., 2014; Straub et al., 2014; Wieland et al., 2014). Additionally, optogenetic stimulation of NAc DA terminals results in a pause in CIN firing and this pause is prolonged when D2Rs are selectively overexpressed in CINs (Gallo et al., 2022). Lastly, pauses generated by DA or local stimulation of the striatum are eliminated in a selective CIN D2 knockout mouse (Augustin et al., 2018; Kharkwal et al., 2016). Taken together, the slice physiology experiments provide evidence that the CIN pause can be induced by DA activation in a CIN D2R-dependent manner while the NHP studies show the necessity for DA and D2Rs for the generation of the pause. However, more recent evidence suggests that the CIN pause is not induced by DA but by cortical, thalamic, or long-range GABAergic inputs (Brown et al., 2012; Cover et al., 2019; Ding et al., 2010; Doig et al., 2014; English et al., 2012; Matsumoto et al., 2000; Zhang et al., 2018). Consistent with this, stimulation of cortical and thalamic inputs to the striatum in slices or in vivo induces a triphasic cholinergic pause. One model suggests that the cholinergic pause is generated by intrinsic properties of CINs. When CINs come out of the early glutamatergic excitation, voltage-gated potassium channels (Kv7.2/7.3) open and induce an after-hyperpolarization that induces the pause. In this model DA plays a role in augmenting the intrinsically induced pause (Zhang et al., 2018). Consistent with this, thalamo-striatal stimulation induced a pause that was shortened but not fully abolished by a D2R antagonist (Cover et al., 2019). However, in earlier influential slice physiology experiments, the pause induced by thalamic stimulation was fully blocked by D2R antagonism suggesting that activation of DA release from intrastriatal DA terminals was responsible for pause generation (Ding et al., 2010). One limitation of the mechanistic studies in rodents has been that they relied on stimulation experiments rather than on DA evoked by natural stimuli. While the early NHP studies suggested necessity for DA in inducing the pause during behavior, these studies lacked the cellular specificity for excluding the possibility that the effects of pharmacological D2R blockage were due to inhibiting D2Rs on CINs vs other neuronal populations. Here, we used genetically encoded biosensors (Labouesse and Patriarchi, 2021) to simultaneously monitor DA and ACh in the dorsal striatum during behavior in mice with pharmacological blockade and/or selective ablation of D2Rs from CINs. Using this approach, we addressed the question of whether the natural stimulus-induced pause is fully dependent on DA or not. We first determined whether changes in DA and ACh levels occur simultaneously to reward-predicting stimuli in mice as has been shown in NHPs via electrophysiological recordings of DA and TAN neurons (Morris et al., 2004). In vivo imaging of ACh and DA levels revealed cue-induced decreases in striatal ACh and increases in DA levels, confirming the ability to measure concomitant ACh dips and DA peaks with functional imaging. Using a Pavlovian learning task, we confirmed that both signals co-occur and develop in parallel during the training of the task. Using a simpler reinforcement task that enables better quantification of the neuromodulator signals, we quantified cue-induced changes in DA and ACh changes after manipulating D2R function. We found that selective ablation of D2Rs from CIN or blocking D2Rs in control mice with the selective D2R antagonist eticlopride did not abolish the stimulus-induced decrease in ACh levels. Rather it shortened the duration of the decrease and enhanced ACh rebound levels in a dose-dependent manner. This indicates that DA is necessary for controlling the overall shape of the ACh signal. During simultaneous recordings experiments, the relationship between DA and ACh was strongest in response to reward-predicting cues but still present during the intertrial interval (ITI) supporting a general mechanism by which DA coordinates ACh levels. At the behavioral level, D2R antagonism increased latency to lever press to a reward-paired lever, but this relationship was abolished when we inactivated CIN D2Rs. Moreover, cue-evoked changes in ACh levels correlated with the latency to press, and short artificial inhibition of CINs at lever extension regulated the latency to press. Altogether this supports a role of the cue-induced ACh signal in the motivation to initiate actions. Results GACh3.0 allows for measuring fast decreases in task-evoked ACh levels First, we validated our experimental approach that uses fiber photometry and genetically encoded fluorescent indicators to simultaneously measure DA and ACh levels. Mice were imaged in separate hemispheres within the same animal as shown in Figure 1A during a continuous reinforcement (CRF) task (Figure 1B). We aligned our photometry signals to the lever extension, which with training becomes a reward-predicting cue. After 3 days of training, we observed an increase in DA (red) and a decrease in ACh (blue) at lever extension presentation (Figure 1C). To confirm that the fluorescent indicator, GACh3.0, is measuring changes in ACh levels (and not movement artifacts or electrical noise), we measured the GACh3.0 signal in the presence of 15 mg/kg scopolamine, a muscarinic antagonist, which targets the GACh3.0 parent receptor (M3R). We found that the competitive antagonist scopolamine abolished the early increase and the subsequent decrease in the fluorescent signal, indicating that GACh3.0 indeed quantifies ACh binding and thus surrounding ACh levels (Figure 1D). Figure 1 with 1 supplement see all Download asset Open asset GACh3.0 reliably measures fast decreases in acetylcholine (ACh) during an instrumental task. (A) Schematic of the surgery setup. All mice were injected with both biosensor viruses (GACh3.0 and dLight1.2) in separate hemispheres of the dorsal medial striatum (DMS) and counterbalanced across mice. Fiber photometry lenses were bilaterally implanted at the site of viral injection to simultaneously monitor ACh and dopamine (DA) in the same mouse. (B) Continuous reinforcement (CRF) task design. Mice were trained to press a lever to retrieve a milk reward for 60 trials/day with a variable intertrial interval (ITI) (40 s). (C) Changes in fluorescence (ΔF/F[%]) aligned to lever extension (time point = 0 s). DA levels (red) increased and ACh levels (blue) decreased, N=5 mice in trained mice. (D) 15 mg/kg of scopolamine (green), an mAChR antagonist, blunts the initial ACh peak and dip compared to saline (black) confirming that the GACh3.0 sensor is reporting changes in ACh levels. N=4 mice. (E) Heatmap of ACh responses aligned to lever extension (time = 0 s) and sorted by the duration of ACh decrease for 300 individual trials (60 trials in 5 mice). (F) Schematic of the surgery setup. ChAT-ires-Cre mice were co-injected with GACh3.0 and Cre-dependent halorhodopsin into the DMS and a fiber photometry lens was implanted at the site of viral injection. (G) Approximation of trials with short dips (bottom) and long dips (top) using the short and long optogenetic inhibition protocol (100 trials, 20 trials/5 mice). To confirm that the GACh3.0 sensor has the kinetics to measure a rapid decrease in ACh levels, we expressed the inhibitory opsin eNpHR3.0 in ChAT-IRES-Cre mice to selectively inhibit CINs. Lever extension induced decreases in ACh levels within 250 ms (Figure 1E). Light activation of eNpHR3.0 in a home cage induced a decrease with even shorter latency (latency to decrease onset 206.4 [186.8–226.1] ms, n=5 mice), which was followed by a rebound in ACh levels (Figure 1F). The rebound is consistent with CINs displaying rebound activity after injecting hyperpolarizing currents in brain slices (Wilson, 2005) and optogenetic inhibition in vivo (English et al., 2012). These data show that GACh3.0 can measure fast decreases in ACh levels. It also indicates that ACh levels are tightly controlled by CIN neuron activity. Variability between animals While analyzing the ACh signals we found that some mice showed an initial peak in ACh levels (Figure 1D) while others did not (Figure 1C). This has been described at the neuronal level when recording from individual neurons (Apicella et al., 1997; Kimura et al., 1984) but here it is observed at the level of ACh levels released by a population of neurons. While the origin of the between animal variability is unclear, we believe that it is related to the location of recording. Generally, more lateral/dorsal recording location showed an initial peak in ACh levels while more medial/ventral location did not show the initial peak (Figure 1—figure supplement 1). The origin for this variability should be addressed in a more systemic way in the future. Simultaneous development of DA and ACh signals in response to a reward-predicting stimulus To determine whether changes in DA and ACh levels in response to reward-predicting stimuli are co-incident, we measured the release of DA and ACh during a Pavlovian reward learning task (Figure 2A). On day 1 of training, we observed an increase in DA (red) and a decrease in ACh (blue) during unexpected reward following the offset of the CS+ (Figure 2C). Over training, we saw these changes in both DA and ACh shift to the onset of the CS+ tone, while decreasing to the now expected reward. We did not observe these changes during CS− trials. We then related the changes in DA and ACh to changes in anticipatory head entries during the CS+ as a measure of learning. We found that both DA and ACh signals correlated well with anticipatory head entries in one animal (Figure 2C). However, other mice did not show any anticipatory responding as this task is non-contingent and head poking is not required to obtain the reward during CS+ trials. These findings indicate that DA and ACh signals co-develop with learning in response to a reward-predicting stimulus. Figure 2 Download asset Open asset Co-development of dopamine (DA) and acetylcholine (ACh) signals to a reward-predicting cue. (A) Pavlovian task design. Mice were trained on 24 (12 CS+, 12 CS−) trials/day for 5 days. Each trial starts with a 10 s tone (CS+ or CS−). At the end of the CS+ a dipper comes up presenting a milk food reward for 5 s. There is an intertrial interval (ITI) variable in length (100 s). (B) Changes in fluorescence (ΔF/F [%]) over 5 days of training for DA (red) and ACh (blue) aligned to CS+ (left) and CS− (right) onset. Signals were averaged over 12 CS+ and 12 CS− trials/day, N=3 mice. (C) Maximum change in DA peak (blue) and ACh dip (red) after CS+ onset over 5 days of training (60 trials) for mouse A (left). Anticipatory responding (black) is calculated as the difference in nose poking during the CS+ quintile with the maximum responses (Q4 or 5) and the first quintile. Correlations between DA and ACh maxima and behavioral responding: r=0.4, p<0.002 and r=–0.41, p<0.002 in mouse A, respectively. Correlation between DA and ACh signals: r=–0.7041, p<0.0001. We did not observe the same correlation between DA/ACh and anticipatory responses in mouse B (middle) or mouse C (right). Correlation between DA and ACh signals: mouse B (r=0.03997, p=0.7617) and mouse C (r=–0.6687, p<0.0001). D2 receptor blockade dose dependently shortens the decrease and enhances the rebound in ACh levels To determine if the cue-induced ACh decrease is dependent on DA activation of D2Rs, we used the CRF task as it allows for more trials per session aiding the quantification of the signal. After systemic delivery of the D2R antagonist eticlopride we found a dose-dependent shortening of the ACh decrease, which uncovered a rebound following the decrease (Figure 3A). We quantified these changes by calculating the area under the curve (AUC), dip duration and dip amplitude. We found that eticlopride significantly reduced the negative AUC (Figure 3B), increased the rebound AUC (Figure 3C), increased the total AUC (Figure 3D), and decreased the dip duration (Figure 3E), while the dip amplitude was not affected by D2R antagonism (Figure 3F). This suggests that D2Rs do not participate in the initial induction of the ACh decrease but do increase the duration of the decrease and prevent rebound activity following the ACh decrease. Since DA neurons are inhibited by D2 auto-receptors, we also analyzed the effect of D2R antagonism on cue-induced DA release and quantified changes in peak amplitude and AUC (Figure 3—figure supplement 1A). We found an overall effect of drug increasing the peak amplitude (Figure 3—figure supplement 1B) with the most prominent increase between saline and 0.1 mg/kg eticlopride. There was no overall effect of drug on the AUC (Figure 3—figure supplement 1C). These results confirm that blocking D2 auto-receptors on DA neurons increases phasic DA release. Figure 3 with 1 supplement see all Download asset Open asset D2R antagonism decreases acetylcholine (ACh) dip duration and enhances rebound. (A) Changes in ACh fluorescence (ΔF/F [%]) aligned to lever extension with saline (black) and increasing doses of eticlopride: 0.1 mg/kg (pink), 0.25 mg/kg (green), 1.0 mg/kg (red), 2.5 mg/kg (orange), and 5.0 mg/kg (blue). N=5 mice. (B) Negative area under the curve (AUC) is reduced by eticlopride in a dose-dependent manner (RM ANOVA: F(1.694, 6.777)=8.756, p=0.0150). (C) The rebound AUC is increased by eticlopride in a dose-dependent manner ( F(1.549, 6.197)=8.833, p=0.0181). (D) Total AUC is increased by eticlopride in a dose-dependent manner (F(1.612, 6.448)=8.724, p=0.0170). (E) Dip duration is decreased by eticlopride in a dose-dependent manner (F(1.392, 5.569)=36.37, p=0.0009). (F) The dip amplitude was not affected by eticlopride (F(2.063, 8.251)=1.864, p=0.2147). Individual CRF trials revealed varying durations of lever extension aligned ACh decreases that we sorted by lever press latency using a heatmap (Figure 4A). Based on this heatmap, we observed longer decreases associated with quick press latencies and two smaller decreases with slower press latencies with the second decrease co-occurring with the lever press. Thus, for press latencies <2 s the ACh decrease is a combination of a cue induced and movement associated pause. To separate the cue induced pause from the movement induced pause, we analyzed trials with press latencies >2 s. We still observed a decrease in the ACh dip duration with increasing doses of eticlopride (Figure 4B). Quantification of the negative AUC revealed a non-significant but trending decrease with increasing doses of eticlopride (Figure 4C), while the rebound AUC increased (Figure 4D), the total AUC increased (Figure 4E), and the dip duration (Figure 4F) decreased. Eticlopride had no effect on the ACh dip amplitude (Figure 4G). We also examined the effect of D2R antagonism on cue-induced DA release for trials with press latencies >2 s (Figure 4—figure supplement 1). Quantification of DA peak amplitude (Figure 4—figure supplement 1B) and AUC (Figure 4—figure supplement 1C) revealed an overall increase in both measures. Moreover, we found a significant increase between saline and 0.1 mg/kg eticlopride for DA peak amplitude (Figure 4—figure supplement 1B). Taken together, these results demonstrate that the cue-induced ACh decrease and rebound levels are regulated by cholinergic D2Rs. Figure 4 with 1 supplement see all Download asset Open asset D2R antagonism shortens cue-evoked acetylcholine (ACh) dip and enhances rebound. (A) Heatmap of ACh responses aligned to lever extension (time = 0 s) for 300 individual trials (60 trials in 5 mice) and sorted by response length (bottom). Blue dots show the lever press, and the pink dots show the head entry for each trial. White dashed box represents the cue-evoked ACh response to the lever extension where press latencies are >2 s. N = 5 mice. (B) Changes in ACh fluorescence (ΔF/F [%]) aligned to lever extension for only trials with press latencies >2 s with increasing doses of eticlopride. (C) Negative area under the curve (AUC) is reduced by eticlopride in a dose-dependent manner (RM ANOVA: F(2.237, 8.950)=3.911, p=0.0569). (D) Rebound AUC is enhanced by eticlopride in a dose-dependent manner (F(1.667, 6.668)=8.143, p=0.0184). (E) Total AUC was increased by eticlopride in a dose-dependent manner (F(1.597, 6.387)=8.542, p=0.0182). (F) Dip duration was significantly decreased by eticlopride in a dose-dependent manner (F(1.657, 6.628)=6.729, p=0.0284). (G) Eticlopride had no effect on the dip amplitude (F(2.722, 10.89)=0.5379, p=0.6503). D2R blockade decreases negative and enhances positive correlations between DA and ACh We further determined the relationship between ACh and DA levels within trials using a Pearson’s correlation analysis. Using a lag analysis, we temporally shifted the ACh recording behind or in front of the DA recording to identify maximal points of correlation. During CRF trials, the strongest correlation is a negative correlation (Figure 5A, label 1, saline: Pearson’s r=–0.475 ± 0.037, N=5) that occurs when ACh lags DA (Lag = –178.92 ± 14.38 ms), which accounts for 22% of the variance in the decrease in ACh being explained by the DA peak. This negative correlation, which reflects the decrease in ACh levels that follows the DA peak, is reduced with eticlopride in a dose-dependent manner (Figure 5B). Next, we found a small positive correlation (Figure 5A, label 2, saline: Pearson’s r=0.039 ± 0.014) when ACh lags DA (Lag = –1.5 ± 0.138 s), which accounts for 0.15% of the variance in the ACh peak being explained by the DA peak. This positive correlation, which reflects the rebound in ACh, is significantly increased with eticlopride (Figure 5C). Figure 5 Download asset Open asset Task-dependent acetylcholine-dopamine (ACh-DA) interactions are altered by D2R antagonism at lever extension. (A) Correlation between ACh and DA during continuous reinforcement (CRF) trials with increasing doses of eticlopride in 5 C57BL/6J mice. The ACh signal moved in front of or behind the DA signal to identify points of highest correlation. The first correlation is a negative correlation (1) with ACh lagging DA (Lag = –178.92 ± 14.38 ms) and the second correlation is a positive correlation (2) with ACh lagging DA (Lag = –1.5 ± 0.138 s). N=5 mice. (B) The negative correlation with the DA peak leading the ACh dip (inset) is significantly reduced dose dependently by eticlopride (RM ANOVA: F(2.596, 10.38)=18.67, p<0.0001). (C) The positive correlation with the DA peak leading the ACh rebound (inset) is enhanced by eticlopride in a dose-dependent manner (F(2.326, 9.303)=4.694, p=0.0352). We then analyzed these correlations during the ITI to determine whether they are only present during stimulus-induced DA/ACh signals or may represent a more general mechanism or coordination (Figure 6A). Of note, we looked for any interaction between DA and ACh regardless of event size. Like CRF trials, we observed two correlations during the ITI; DA peak leads ACh dip (Pearson’s r=–0.355 ± 0.065 and Lag = –212.34 ± 16.91 ms) and DA peak leads ACh peak/rebound (Pearson’s r=0.058 ± 0.021 and Lag = –1.41 ± 0.19 s), which accounts for 12.6% of the decrease in ACh being explained by the DA peak and 0.34% of the ACh peak by the DA peak, respectively. We found that eticlopride decreases the negative correlation in a dose-dependent manner (Figure 6B). Eticlopride also increased the positive correlation, which represents the ACh rebound (Figure 6C). These results indicate that DA-ACh correlations are dependent on D2Rs. While they are strong during salient cue presentations the relationship between both signals still exists during the ITI reflecting a general mechanism of co-regulation. Figure 6 Download asset Open asset Acetylcholine-dopamine (ACh-DA) interactions are altered by D2R antagonism during the intertrial interval (ITI). (A) Correlation between ACh and DA during the ITI with increasing doses of eticlopride in C57BL/6J mice. We observe the same two correlations during the ITI: a negative correlation (1) with ACh lagging DA (Lag = –212.34 ± 16.91 ms) and a positive correlation (2) with ACh lagging DA (Lag = –1.41 ± 0.19 s). N = 5 mice. (B) The negative correlation with the DA peak leading the ACh dip (inset) is decreased by eticlopride in a dose-dependent manner (RM ANOVA: F(1.850, 7.400)=4.689, p=0.0502). (C) The positive correlation with the DA peak leading the ACh rebound (inset) is increased dose dependently by eticlopride (F(2.129, 8.515)=4.877, p=0.0373). Genetic inactivation of D2Rs from CINs shortens the decrease in ACh levels Systemic eticlopride injections block all D2Rs. To determine the specific modulatory role that D2Rs present in CINs play in the cholinergic pause, we used mouse genetics to selectively inactivate D2Rs from CINs (ChATDrd2KO mice). We measured a smaller and shorter decrease in ACh levels in ChATDrd2KO mice compared to control mice in trials with press latencies >2 s (Figure 7A–C) or when taking all trials into account (data not shown). Note that the effects of D2R deletion differed from the highest dose of eticlopride in that ChATDrd2KO mice showed differences in the dip amplitude while eticlopride did not. Figure 7 with 1 supplement see all Download asset Open asset Selective D2R ablation from cholinergic interneurons (CINs) alters the cue-evoked acetylcholine (ACh) dip. (A) Changes in ACh fluorescence (ΔF/F [%]) aligned to lever extension for only trials with press latencies >2 s for Drd2fl/fl control (black) and ChATDrd2KO (blue) mice, N=4 mice/genotype. (B) Dip amplitude is significantly smaller in ChATDrd2KO animals compared to controls (t-test: p=0.0107). (C) Dip duration is significantly shorter in ChATDrd2KO mice compared to Drd2fl/fl controls (p=0.0351). In contrast to ACh levels, stimulus-induced DA release was not altered in ChATDrd2KO mice (Figure 7—figure supplement 1). This result indicates that loss of cholinergic D2Rs does not affect stimulus-induced DA release and confirm that the effects of DA regulation of the ACh dip are mediated by CIN D2Rs and not an indirect effect by potential changes in DA levels. DA-mediated changes in ACh levels are dependent on CIN D2Rs Next, we determined if D2Rs present in CINs are necessary for the effect of D2R antagonism on modulating the cue-induced changes in ACh levels. Control Drd2fl/fl mice were more sensitive to eticlopride than the C57BL/6J wild-type mice of Figure 4 as they did not complete any trials with the two highest doses, 2.5 and 5.0 mg/kg (Figure 8A–F). Quantification of the ACh signal using the 3 lower doses revealed a decrease in the negative AUC (Figure 8B), an increase in the rebound AUC (Figure 8C), an increase in the total AUC (Figure 8D), and a decrease in dip duration (Figure 8E) that were comparable to what we measured in the C57BL/6J mice (Figure 4). Like the C57BL/6J mice, there was no effect on ACh dip amplitude with eticlopride (Figure 8F). In contrast, in ChATDrd2KO mice, we observed no effect of eticlopride on cue-induced changes in ACh levels (Figure 8G) neither on the negative AUC (Figure 8H), the rebound AUC (Figure 8I), total AUC (Figure 8J), dip duration (Figure 8K), or dip amplitude (Figure 8L). When Drd2fl/fl and ChATDrd2KO mice were analyzed together we measured a gene × eticlopride interaction for negative AUC (genotype × dose: F(3, 18)=3.113, p=0.0522), rebound AUC (genotype × dose: F(3,18)=4.600, p=0.0147), total AUC (genotype × dose: F(3,18)=8.106, p=0.0013), dip duration (genotype × dose: F(3,18)=10.41, p=0.0003) but not dip amplitude (genotype × dose: F(3,18)=1.611, p=0.2219). These results confirm that CIN D2Rs are responsible for the modulation of the ACh signal elicited by D2R antagonism. Figure 8 Download asset Open asset D2R antagonism does not alter the cue-evoked acetylcholine (ACh) d" @default.
• W4301934688 created "2022-10-06" @default.
• W4301934688 creator A5085620061 @default.
• W4301934688 date "2022-02-15" @default.
• W4301934688 modified "2023-09-30" @default.
• W4301934688 title "Editor's evaluation: Dopamine D2Rs coordinate cue-evoked changes in striatal acetylcholine levels" @default.
• W4301934688 doi "https://doi.org/10.7554/elife.76111.sa0" @default.
• W4301934688 hasPublicationYear "2022" @default.
• W4301934688 type Work @default.
• W4301934688 citedByCount "0" @default.
• W4301934688 crossrefType "peer-review" @default.
• W4301934688 hasAuthorship W4301934688A5085620061 @default.
• W4301934688 hasBestOaLocation W43019346881 @default.
• W4301934688 hasConcept C134018914 @default.
• W4301934688 hasConcept C15744967 @default.
• W4301934688 hasConcept C169760540 @default.
• W4301934688 hasConcept C2775910092 @default.
• W4301934688 hasConcept C513476851 @default.
• W4301934688 hasConcept C71924100 @default.
• W4301934688 hasConceptScore W4301934688C134018914 @default.
• W4301934688 hasConceptScore W4301934688C15744967 @default.
• W4301934688 hasConceptScore W4301934688C169760540 @default.
• W4301934688 hasConceptScore W4301934688C2775910092 @default.
• W4301934688 hasConceptScore W4301934688C513476851 @default.
• W4301934688 hasConceptScore W4301934688C71924100 @default.
• W4301934688 hasLocation W43019346881 @default.
• W4301934688 hasOpenAccess W4301934688 @default.
• W4301934688 hasPrimaryLocation W43019346881 @default.
• W4301934688 hasRelatedWork W1983138582 @default.
• W4301934688 hasRelatedWork W2070604861 @default.
• W4301934688 hasRelatedWork W2072920560 @default.
• W4301934688 hasRelatedWork W2114715627 @default.
• W4301934688 hasRelatedWork W2794928967 @default.
• W4301934688 hasRelatedWork W3114196304 @default.
• W4301934688 hasRelatedWork W4320006214 @default.
• W4301934688 hasRelatedWork W4366981411 @default.
• W4301934688 hasRelatedWork W4382874531 @default.
• W4301934688 hasRelatedWork W4385696977 @default.
• W4301934688 isParatext "false" @default.
• W4301934688 isRetracted "false" @default.
• W4301934688 workType "peer-review" @default.