No abstract available.
Animals ; Clomipramine* ; Preoptic Area* ; Rats* ; Serotonin Uptake Inhibitors* ; Serotonin*

A growing number of studies have identified sex differences in response to general anesthesia; however, the underlying neural mechanisms are unclear. The medial preoptic area (MPA), an important sexually dimorphic structure and a critical hub for regulating consciousness transition, is enriched with estrogen receptor alpha (ERα), particularly in neuronal clusters that participate in regulating sleep. We found that male mice were more sensitive to sevoflurane. Pharmacological inhibition of ERα in the MPA abolished the sex differences in sevoflurane anesthesia, in particular by extending the induction time and facilitating emergence in males but not in females. Suppression of ERα in vitro inhibited GABAergic and glutamatergic neurons of the MPA in males but not in females. Furthermore, ERα knockdown in GABAergic neurons of the male MPA was sufficient to eliminate sex differences during sevoflurane anesthesia. Collectively, MPA ERα positively regulates the activity of MPA GABAergic neurons in males but not in females, which contributes to the sex difference of mice in sevoflurane anesthesia.
Anesthesia ; Animals ; Estrogen Receptor alpha/metabolism* ; Female ; Male ; Mice ; Preoptic Area ; Sevoflurane/pharmacology* ; Sex Characteristics

The present study investigated the sedative effects of Sophora flavescens (SF) and its bioactive compound, matrine through performing locomotor activity test and the electroencephalography (EEG) analysis in the rat. The underlying neural mechanism of their beneficial effects was determined by assessing c-Fos immunoreactivity and serotonin (5-HT) in the brain utilizing immunohistochemical method and enzyme-linked immunosorbent assay. The results showed that SF and matrine administration had an effect on normalization of caffeine-induced hyperactivity and promoting a shift toward non-rapid eye movement (NREM) sleep. c-Fos-immunoreactivity and 5-HT level in the ventrolateral preoptic nucleus (VLPO), a sleep promoting region, were increased in the both SF and matrine-injected groups. In conclusion, SF and its bioactive compound, matrine alleviated caffeine-induced hyperactivity and promoted NREM sleep by activating VLPO neurons and modulating serotonergic transmission. It is suggested that SF might be a useful natural alternatives for hypnotic medicine.
Animals ; Brain ; Electroencephalography ; Enzyme-Linked Immunosorbent Assay ; Eye Movements ; Hypnotics and Sedatives* ; Methods ; Motor Activity ; Neurons ; Preoptic Area ; Rats ; Serotonin ; Sophora*

The present study investigated the sedative effects of Sophora flavescens (SF) and its bioactive compound, matrine through performing locomotor activity test and the electroencephalography (EEG) analysis in the rat. The underlying neural mechanism of their beneficial effects was determined by assessing c-Fos immunoreactivity and serotonin (5-HT) in the brain utilizing immunohistochemical method and enzyme-linked immunosorbent assay. The results showed that SF and matrine administration had an effect on normalization of caffeine-induced hyperactivity and promoting a shift toward non-rapid eye movement (NREM) sleep. c-Fos-immunoreactivity and 5-HT level in the ventrolateral preoptic nucleus (VLPO), a sleep promoting region, were increased in the both SF and matrine-injected groups. In conclusion, SF and its bioactive compound, matrine alleviated caffeine-induced hyperactivity and promoted NREM sleep by activating VLPO neurons and modulating serotonergic transmission. It is suggested that SF might be a useful natural alternatives for hypnotic medicine.
Animals ; Brain ; Electroencephalography ; Enzyme-Linked Immunosorbent Assay ; Eye Movements ; Hypnotics and Sedatives* ; Methods ; Motor Activity ; Neurons ; Preoptic Area ; Rats ; Serotonin ; Sophora*

Within the medial preoptic area[MPOA], several cytoarchitectonically defined cell groups are sexually dimorphic in their morphology. Specially, the sexual dimorphic nucleus of the preoptic area[SDN-POA] is reported an example of a morphological sex difference in the rat hypothalamus which is influenced by gonadal steroid hormones. Thus, we detemined the distribution of Galanin-immunoreactive[Gal-I] cells and fibers within MPOA and their morphological response to gonadal steroids which is influenced by gonadectomy or prenatal restosterone treatments were observed. The Gal-I cells were appeared within the medial preoptic area. In the males, the volume and number of Gal-I nerve cell bodies were greater than that of females. But the female which treated prenatal testosterone injection had many Gal-I neurons than infact female. And the males that decreased the volume of gonadal hormone by gonadectomy were decreased the volume and number of Gal-I neurons than that of normal males. These results suggest that galaninergic cells within the medial preoptic area are influenced by gonadal steroid hormone[testosterone] in the regulation of sexually dimorphic function.
Animals ; Female ; Galanin* ; Gonadal Steroid Hormones ; Gonads ; Humans ; Hypothalamus ; Immunohistochemistry ; Male ; Neurons ; Preoptic Area* ; Rats* ; Sex Characteristics ; Steroids ; Testosterone*

Nonylphenol (NP) is a widespread environmental pollutant that has been shown to exert both toxic and estrogenic effects on mammalian cells. As the effects of NP on the reproductive system of adult male vertebrates are virtually unknown, we investigated not only the changes of reproductive hormone secretion in serum after chronic exposure to NP but also, in order to identify the site of its action, the reproductive hormone secretion in serum 48 hours after microinfusion of NP within hypothalamic preoptic area (POA). In the chronic exposure, the luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone in serum were decreased but prolactin (PRL) concentrations were increased. The LH, FSH, and testosterone in serum were decreased through the direct infusion of NP into POA, while there was no difference in mean serum prolactin between NP and control groups. These observations suggest that NP as endocrine disruptor has modulatory effects on hypothalamo-pituitary-gonadalaxis and that the site of action of NP could be hypothalamic POA.
Adult* ; Animals ; Estrogens ; Ethanol ; Follicle Stimulating Hormone ; Humans ; Luteinizing Hormone ; Male* ; Poa ; Preoptic Area ; Prolactin* ; Rats* ; Testosterone* ; Vertebrates

A current hypothesis of sleep-wake regulation proposes that the sleep process starts with the activation of sleep-promoting neurons located in the preoptic area of the anterior hypothalamus. This activation leads to the inhibition of wake-promoting neurons located in the posterior hypothalamus, basal forebrain, and mesopontine tegmentum, which, in turn removes inhibition from the sleep-promoting structures(i.e., disinhibition) to initiate the sleep process. Mutual inhibition between these wake- and sleep-promoting neurons results in switching properties that define discrete wakeful and sleep states with sharp transitions between them. Wake-promoting nuclei include the orexinergic lateral hypothalamic/perifornical area, the histaminergic tuberomammillary nucleus, the cholinergic pedunculopontine tegmental nucleus, the noradrenergic locus coeruleus, the 5-hydroxytryptaminergic raphe nuclei, and possibly the dopaminergic ventral tegmental area. The major sleep-promoting nucleus is the GABAergic ventrolateral preoptic nucleus of the hypothalamus. The regulation of sleep is classically viewed as the dual interaction of circadian(SCN-based) and homeostatic processes, and the propensity to be asleep or awake at any given time is a consequence of a sleep debt and its interaction with signals from the SCN circadian clock. To better understand the mechanisms of sleep and wakefulness, the focus of pharmacotherapy is on targeting specific therapies to the particular defect in sleep-wake regulation.
Circadian Clocks ; Circadian Rhythm ; Drug Therapy* ; Hypothalamic Area, Lateral ; Hypothalamus ; Hypothalamus, Anterior ; Hypothalamus, Posterior ; Locus Coeruleus ; Neuroanatomy* ; Neurons ; Pedunculopontine Tegmental Nucleus ; Preoptic Area ; Prosencephalon ; Raphe Nuclei ; Sleep Wake Disorders ; Ventral Tegmental Area ; Wakefulness

OBJECTIVETo investigate the effects of androgen on sexually dimorphism nucleus in preoptic area (SDN-POA) and anteroventral periventricular nucleus (AVPV) before sexual differentiation of the brain in female rats.

METHODSNeonatal female SD rats (n=12) were randomly divided into two groups: androgen group and control group. Twenty-four hours after birth animals were subjected to intraperitoneal injection of 50 microl of testosterone propionate (TP,10.0 g/L) or aseptic oil as control. The rats were sacrificed 60 days after the injection and the brains were collected for crystal violet staining. LEICA Q Win system was applied in detecting the boundaries of SDN-POA and AVPV, then the volumes of SDN-POA and AVPV were calculated.

RESULTSThe volumes of SDN-POA in androgen group were significantly larger than those in control group [(16.77+/-2.68) vs (8.99+/-1.42)mm(3)x10(-3), P<0.01], while the volumes of AVPV in androgen group were significantly smaller than those in control group [(9.14+/-1.16) vs (14.62+/-2.80)mm(3)x10(-3), P<0.01].

CONCLUSIONExogenous androgen rendered before sexual differentiation in female rats results in enlargement of SDN-POA volumes and reduction of AVPV.

Androgens ; pharmacology ; Animals ; Animals, Newborn ; Female ; Paraventricular Hypothalamic Nucleus ; anatomy & histology ; drug effects ; Preoptic Area ; anatomy & histology ; drug effects ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Sex Differentiation

AIMTo investigate the possible central mechanism of antipyretic effects of Chinese medicine gypsum.

METHODSGypsum was injected after the fever model was established. The firing rate of thermosensitive neurons in preoptic-anterior hypothalamus(PO/AH) region was recorded by using extracellular microelectrode technique.

RESULTSThe injection of pyrogen evoked decrease in firing rate of the warm-sensitive neurons and increase in the cold-sensitive neurons in the region of PO/AH; the changes of the firing rate of pyrogen- treated warm-sensitive and cold-sensitive neurons could be reversed by the injection of gypsum.

CONCLUSIONThe result may suggest that antipyretic action of gypsum is mediated by its influences on the thermosensitivity neurons in the region of PO/AH.

Action Potentials ; Animals ; Antipyretics ; pharmacology ; Calcium Sulfate ; pharmacology ; Cats ; Fever ; physiopathology ; Hypothalamus, Anterior ; physiopathology ; Male ; Materia Medica ; pharmacology ; Neurons ; physiology ; Preoptic Area ; physiopathology ; Pyrogens

Animals ; Arcuate Nucleus of Hypothalamus ; drug effects ; metabolism ; Body Temperature Regulation ; Cyclic AMP ; metabolism ; Dinoprostone ; metabolism ; Eugenol ; pharmacology ; Fever ; metabolism ; Preoptic Area ; drug effects ; metabolism ; Rabbits