Diverse midbrain dopaminergic neuron subtypes and implications for complex clinical symptoms of Parkinson's disease.

Parkinson's disease (PD), the most common degenerative movement disorder, is clinically manifested with various motor and non-motor symptoms. Degeneration of midbrain (SNc) dopaminergic neurons (DANs) is generally attributed to the motor syndrome. The underlying neuronal mechanisms of non-motor syndrome are largely unexplored.

Function and Regulation of ALDH1A1-Positive Nigrostriatal Dopaminergic Neurons in Motor Control and Parkinson's Disease.

Dopamine is an important chemical messenger in the brain, which modulates movement, reward, motivation, and memory. Different populations of neurons can produce and release dopamine in the brain and regulate different behaviors. Here we focus our discussion on a small but distinct group of dopamine-producing neurons, which display the most profound loss in the ventral of patients with Parkinson's disease.

Gas chromatography - Mass spectrometry as a preferred method for quantification of insect hemolymph sugars.

Insects, due to their small size, have limited energy storage space, but they also have high metabolic rate, so their hemolymph sugars are incredibly dynamic and play a number of important physiological functional roles in maintaining energetic homeostasis. In contrast to vertebrates, trehalose is generally the primary sugar found in insect hemolymph, which is followed by glucose and fructose. Many analytical chemistry methods exist to measure sugars, yet a direct comparison of methods that can measure all three simultaneously, and trehalose in particular, from low sample volumes, are sparse.

Appetite is correlated with octopamine and hemolymph sugar levels in forager honeybees.

Insects have rapidly changing energy demands, so they primarily rely on hemolymph and other carbohydrates to carry out life activities. However, how gustatory responsiveness and hemolymph sugar levels coordinate with one another to maintain energetic homeostasis in insects remains largely unknown for the highly social honeybee that goes through large physiological and behavioral changes. The potential role of biogenic amines and neuropeptides in the connection between the regulation of appetite and fluctuating sugar levels in the hemolymph, due to starvation, as the bee ages, was investigated.