RESUMO

While the role of the ascending dopaminergic system in brain function and dysfunction has been a subject of extensive research, the role of the descending dopaminergic system in spinal cord function and dysfunction is just beginning to be understood. Adenosine plays a key role in the inhibitory control of the ascending dopaminergic system, largely dependent on functional complexes of specific subtypes of adenosine and dopamine receptors. Combining a selective destabilizing peptide strategy with a proximity ligation assay and patch-clamp electrophysiology in slices from male mouse lumbar spinal cord, the present study demonstrates the existence of adenosine A1-dopamine D1 receptor heteromers in the spinal motoneuron by which adenosine tonically inhibits D1 receptor-mediated signaling. A1-D1 receptor heteromers play a significant control of the motoneuron excitability, represent main targets for the excitatory effects of caffeine in the spinal cord and can constitute new targets for the pharmacological therapy after spinal cord injury, motor aging-associated disorders and restless legs syndrome.

Assuntos

Cafeína/farmacologia , Neurônios Motores/efeitos dos fármacos , Receptores de Dopamina D1/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Adenosina/farmacologia , Células Cultivadas , Dopamina/farmacologia , Humanos , Neurônios Eferentes/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacos

RESUMO

Background: The purpose of this study was to determine energy drink (ED) consumption patterns among Hispanic college students. We measured the prevalence and frequency of ED consumption according to gender, degree programs, and specific university-related and social situations. In addition, we assessed the frequency of consumption of EDs mixed with alcoholic beverages. Methods: A total of 508 college students from the University of Puerto Rico, the largest Hispanic institution of higher education statewide, completed an online questionnaire. Results: Twenty-one percent of participants reported consuming EDs with the majority consuming EDs either occasionally (every 2-3 months) or at least once or twice a month. Men were found to be more likely to consume EDs than women. Undergraduate students were found less likely to consume EDs than graduate students. Most students consumed EDs while studying and during social activities. More than one-third of participants that consume EDs admitted mixing them with an alcoholic beverage. Graduate students were found to consume EDs mixed with alcohol more often. Conclusions: The majority of students consumed EDs occasionally and while studying. Most side effects reported after consuming EDs were similar to previous findings. The higher consumption of EDs and of EDs mixed with alcohol by students in graduate programs could be explained by a higher and more complex study load requiring longer periods of wakefulness and concentration. Future studies looking at the consumption patterns of EDs in more competitive graduate programs such as medical and/or dentistry school should be considered.