Effects
of acute nicotine (500 nm) on DA release probability and its sensitivity to activity were apparent. However, in NAc there was downregulation of the functional dominance of α6-nAChRs (α6α4β2β3), and an emergence in function of Z-VAD-FMK purchase non-α6* nAChRs. In CPu, there was no change in the control of DA release by its α6 nAChRs (α6β2β3) relative to non-α6. These data suggest that chronic nicotine subtly modifies the regulation of DA transmission, which, in NAc, is through downregulation of function of a susceptible population of α6α4β2β3 nAChRs. This imbalance in function of α6:non-α6 nAChRs might contribute to DA dysregulation in nicotine addiction. “
“The orbitofrontal cortex (oPFC) sends substantial projections to the ventrolateral striatum and aspects of the nucleus
accumbens that are, functionally, poorly understood. This is despite probable cortico-striatal involvement in multiple diseases such as addiction and obsessive-compulsive disorder. Here we surgically disconnected the oPFC from the ventrolateral striatum using unilateral asymmetric lesions in mice and classified instrumental decision-making strategies. Mice with symmetric lesions that spared one Everolimus supplier oPFC–striatal network served as controls. As a complementary approach, we selectively knocked down Brain-derived neurotrophic many factor (Bdnf) bilaterally in the oPFC and ascertained behavioral and neurobiological consequences within the downstream striatum. oPFC–striatal disconnection and oPFC Bdnf knockdown blocked sensitivity to outcome-predictive relationships in both food-reinforced and cocaine-associated settings. Bdnf knockdown simultaneously regulated striatal BDNF expression, and striatal c-Fos predicted sensitivity to action–outcome associative
contingencies. Previous evidence strongly implicates the dorsolateral striatum in stimulus–response habit formation. Our findings thus provide novel evidence for functional compartmentalisation within the lateral striatum, with the dorsal compartment subserving classical stimulus–response habit systems and a ventral compartment coordinating outcome-based decision-making via oPFC interactions. This compartmentalisation may apply to both ‘natural’, as in the case of food-reinforced behavior, and ‘pathological’, as in the case of cocaine-seeking, contexts. “
“Metformin is currently the first-line treatment drug for type 2 diabetes. Metformin is a well-known activator of AMP-activated protein kinase (AMPK). In experimental studies, metformin has been shown to exert direct vascular effects by increasing vascular endothelial growth factor expression and improving microvascular density.