English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Tools annual

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Presents the access of premium content as premium feature

Premium Content

Global: Zendy Plus annual

Global: Zendy Free Plan

Since estradiol attenuates cannabinoid-induced increases in energy intake, energy expenditure, and transmission at proopiomelanocortin (POMC) synapses in the hypothalamic arcuate nucleus (ARC), we tested the hypothesis that neuronal nitric oxide synthase (nNOS) plays an integral role. To this end, whole animal experiments were carried out in gonadectomized female guinea pigs. Estradiol benzoate (EB; 10 μg sc) decreased incremental food intake as well as O2 consumption, CO2 production, and metabolic heat production as early as 2 h postadministration. This was associated with increased phosphorylation of nNOS (pnNOS), as evidenced by an elevated ratio of pnNOS to nNOS in the ARC. Administration of the cannabinoid receptor agonist WIN 55,212-2 (3 μg icv) into the third ventricle evoked hyperphagia as early as 1 h postadministration, which was blocked by EB and restored by the nonselective NOS inhibitor N-nitro-L-arginine methyl ester hydrochloride (L-NAME; 100 μg icv) when the latter was combined with the steroid. Whole cell patch-clamp recordings showed that 17β-estradiol (E2; 100 nM) rapidly diminished cannabinoid-induced decreases in miniature excitatory postsynaptic current frequency, which was mimicked by pretreatment with the NOS substrate L-arginine (30 μM) and abrogated by L-NAME (300 μM). Furthermore, E2 antagonized endocannabinoid-mediated depolarization-induced suppression of excitation, which was nullified by the nNOS-selective inhibitor N5-[imino(propylamino)methyl]-L-ornithine hydrochloride (10 μM). These effects occurred in a sizable number of identified POMC neurons. Taken together, the estradiol-induced decrease in energy intake is mediated by a decrease in cannabinoid sensitivity within the ARC feeding circuitry through the activation of nNOS. These findings provide compelling evidence for the need to develop rational, gender-specific therapies to help treat metabolic disorders such as cachexia and obesity.

Role of neuronal nitric oxide synthase in the estrogenic attenuation of cannabinoid-induced changes in energy homeostasis