Together, these studies provide us with an excellent—though incomplete—neural framework to understand how converging sensory inputs are interpreted to induce a selection between alternative behavioral outputs. The available data point to the P1 cluster as the critical central neurons that trigger singing (and other aspects of the courtship routine), but how might these neurons weigh up positive and negative sensory influences
on the decision to initiate courtship? A hint is offered by finer-scale thermal activation experiments of von Philipsborn et al. (2011), who found that Venetoclax at least ten out of 20 individual P1 neurons must express TrpA1 to induce singing. While it is unknown whether these cells are functionally homogeneous, it is intriguing to speculate that attainment of this threshold number of activated P1 neurons in wild-type flies may be what tips INCB018424 purchase the balance in their mind in favor of courting. Future high-resolution anatomical mapping and physiological characterization of excitatory and inhibitory synaptic inputs to these neurons from different sensory systems, as well as their precise output pathways may reveal the cellular mechanisms by which neural circuits make decisions. “
“Given the increasing prevalence of obesity and the devastating comorbidities associated with obesity, identifying effective antiobesity strategies is
more imperative than ever. Although the underlying causes of the obesity epidemic are multifactorial, exposure to high-caloric diet (Western diet) is thought to be one of the major reasons. In order to mimic human obesity in animal models, a widely accepted strategy involves inducing obesity in rodent models with high-fat diet (HFD) feeding. The HFD feeding can induce obesity and metabolic disorders in rodents that resemble the human metabolic syndrome (Buettner et al., 2007). Thus, important antiobesity drug targets can be identified with HFD-induced obesity models. Research efforts in the last decades have established that the hypothalamus plays a central role in body weight regulation.
The hypothalamus contains diverse groups of body weight-regulating neurons that release distinct neurotransmitters, the most studied of which are neuropeptides (Elmquist others et al., 2005). Recent evidence suggests that the oxytocin-releasing neurons, located in the paraventricular hypothalamus (PVH) and the supraoptic nucleus, are implicated in body weight regulation in addition to their well-established role in social cognition (Donaldson and Young, 2008). Reduced oxytocin expression has been associated with mouse models of obesity (Kublaoui et al., 2008); pharmacological studies demonstrate that oxytocin inhibits feeding involving a projection from the PVH to the hindbrain, where meal size is regulated (Blevins et al.