کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2534004 1559073 2009 10 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Estrogen rapidly attenuates cannabinoid-induced changes in energy homeostasis
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب سلولی و مولکولی
پیش نمایش صفحه اول مقاله
Estrogen rapidly attenuates cannabinoid-induced changes in energy homeostasis
چکیده انگلیسی
We examined whether estrogen negatively modulates cannabinoid-induced regulation of food intake, core body temperature and neurotransmission at proopiomelanocortin (POMC) synapses. Food intake was evaluated in ovariectomized female guinea pigs abdominally implanted with thermal DataLoggers and treated s.c. with the cannabinoid CB1/CB2 receptor agonist WIN 55,212-2, the CB1 receptor antagonist AM251 or their cremephor/ethanol/0.9% saline vehicle, and with estradiol benzoate (EB) or its sesame oil vehicle. Whole-cell patch clamp recordings were performed in slices through the arcuate nucleus. WIN 55,212-2 produced dose- and time-dependent increases in food intake. EB decreased food intake 8-24 h after administration, but rapidly and completely blocked the increase in consumption caused by WIN 55,212-2. EB also attenuated the WIN 55,212-2-induced decrease in core body temperature. The AM251-induced decrease in food intake was unaffected. The diminution of the WIN 55,212-2-induced increase in food intake caused by EB correlated with a marked attenuation of cannabinoid receptor-mediated decreases in glutamatergic miniature excitatory postsynaptic current frequency occurring within 10-15 min of steroid application. Furthermore, EB completely blocked the depolarizing shift in the inactivation curve for the A-type K+ current caused by WIN 55,212-2. The EB-mediated, physiologic antagonism of these presynaptic and postsynaptic actions elicited upon cannabinoid receptor activation was observed in arcuate neurons immunopositive for phenotypic markers of POMC neurons. These data reveal that estrogens negatively modulate cannabinoid-induced changes in appetite, body temperature and POMC neuronal activity. They also impart insight into the neuroanatomical substrates and effector systems upon which these counter-regulatory factors converge in the control of energy homeostasis.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Pharmacology - Volume 622, Issues 1–3, 10 November 2009, Pages 15-24
نویسندگان
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