Complex sex and estrous cycle differences in spontaneous transient adenosine. Issue 2 (2nd March 2020)

• Record Type: Journal Article
• Authors: Borgus, Jason R.; Puthongkham, Pumidech; Venton, B. Jill
• Is Part Of: Journal of neurochemistry. Volume 153:Issue 2(2020)
• Page Start: 216
• Page End: 229
• Publication Date: 2020-03-02
• Subjects: adenosine -- estrous cycle -- fast scan cyclic voltammetry -- FSCV -- in vivo -- sex differences; Neurochemistry -- Periodicals; 616.8042
• DOI: 10.1111/jnc.14981
• Languages: English
• ISSNs: 0022-3042

Abstract

Abstract: Adenosine is a ubiquitous neuromodulator that plays a role in sleep, vasodilation, and immune response and manipulating the adenosine system could be therapeutic for Parkinson's disease or ischemic stroke. Spontaneous transient adenosine release provides rapid neuromodulation; however, little is known about the effect of sex as a biological variable on adenosine signaling and this is vital information for designing therapeutics. Here, we investigate sex differences in spontaneous, transient adenosine release using fast‐scan cyclic voltammetry to measure adenosine in vivo in the hippocampus CA1, basolateral amygdala, and prefrontal cortex. The frequency and concentration of transient adenosine release were compared by sex and brain region, and in females, the stage of estrous. Females had larger concentration transients in the hippocampus (0.161 ± 0.003 µM) and the amygdala (0.182 ± 0.006 µM) than males (hippocampus: 0.134 ± 0.003, amygdala: 0.115 ± 0.002 µM), but the males had a higher frequency of events. In the prefrontal cortex, the trends were reversed. Males had higher concentrations (0.189 ± 0.003 µM) than females (0.170 ± 0.002 µM), but females had higher frequencies. Examining stages of the estrous cycle, in the hippocampus, adenosine transients are higher concentration during proestrus and diestrus. In the cortex, adenosine transients were higher in concentration during proestrus, but were lower during all other stages. Thus, sex and estrous cycle differences in spontaneous adenosine are complex, and not completely consistent from region to region. Understanding these complex differences in spontaneous adenosine between the sexes and during different stages of estrous is important for designing effective treatments manipulating adenosine as a neuromodulator. Abstract : We investigated sex differences in spontaneous, transient adenosine release in three brain regions. In the hippocampus CA1 and basolateral amygdala, females had larger concentration transients, but males had a higher frequency of events. In the prefrontal cortex, the trends were reversed. In females, transient adenosine release varied in frequency and concentration during the estrous cycle. Thus, sex and estrous cycle differences in spontaneous adenosine are complex, and not consistent from region to region, and these complexities should be taken into account when considering the neuromodulatory effects of adenosine.