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The Journal of Experimental Biology Sep 2020Social preferences enable animals to selectively interact with some individuals over others. One influential idea for the evolution of social preferences is that...
Social preferences enable animals to selectively interact with some individuals over others. One influential idea for the evolution of social preferences is that preferred signals evolve because they elicit greater neural responses from sensory systems. However, in juvenile plains spadefoot toad (), a species with condition-dependent mating preferences, responses of the preoptic area, but not of the auditory midbrain, mirror adult social preferences. To examine whether this separation of signal representation from signal valuation generalizes to other anurans, we compared the relative contributions of noradrenergic signalling in the preoptic area and auditory midbrain of and its close relative We manipulated body condition in juvenile toads by controlling diet and used high pressure liquid chromatography to compare call-induced levels of noradrenaline and its metabolite MHPG in the auditory midbrain and preoptic area of the two species. We found that calls from the two species induced different levels of noradrenaline and MHPG in the auditory system, with higher levels measured in both species for the more energetic call. In contrast, noradrenaline levels in the preoptic area mirrored patterns of social preferences in both and That is, noradrenaline levels were higher in response to the preferred calls within each species and were modified by diet in (with condition-dependent preferences) but not (with condition-independent preferences). Our results are consistent with a potentially important role for preoptic noradrenaline in the development of social preferences and indicate that it could be a target of selection in the evolution of condition-dependent social preferences.
Topics: Animals; Anura; Bufonidae; Norepinephrine; Preoptic Area; Reproduction
PubMed: 32647019
DOI: 10.1242/jeb.214148 -
International Journal of Molecular... Jul 2022The mammalian preoptic area (POA) has large populations of calbindin (CB), calretinin (CR) and parvalbumin (PV) neurons, but phenotypes of these cells are unknown....
The mammalian preoptic area (POA) has large populations of calbindin (CB), calretinin (CR) and parvalbumin (PV) neurons, but phenotypes of these cells are unknown. Therefore, the question is whether neurons expressing CB, CR, and/or PV are GABAergic or glutamatergic. Double-immunofluorescence staining followed by epifluorescence and confocal microscopy was used to determine the coexpression patterns of CB, CR and PV expressing neurons with vesicular GABA transporters (VGAT) as specific markers of GABAergic neurons and vesicular glutamate transporters (VGLUT 2) as specific markers of glutamatergic neurons. The guinea pig was adopted as, like humans, it has a reproductive cycle with a true luteal phase and a long gestation period. The results demonstrated that in the guinea pig POA of both sexes, ~80% of CB+ and ~90% of CR+ neurons coexpress VGAT; however, one-fifth of CB+ neurons and one-third of CR+ cells coexpress VGLUT. About two-thirds of PV+ neurons express VGAT, and similar proportion of them coexpress VGLUT. Thus, many CB+, CR+ and PV+ neurons may be exclusively GABAergic (VGAT-expressing cells) or glutamatergic (VGLUT-expressing cells); however, at least a small fraction of CR+ cells and at least one-third of PV+ cells are likely neurons with a dual GABA/glutamate phenotype that may coexpress both transporters.
Topics: Animals; Calbindin 2; Calbindins; Calcium-Binding Proteins; Female; GABAergic Neurons; Guinea Pigs; Humans; Male; Mammals; Parvalbumins; Phenotype; Preoptic Area
PubMed: 35887305
DOI: 10.3390/ijms23147963 -
Brain Research May 2019Normal glucose homeostasis depends on the capacity of pancreatic β-cells to adjust insulin secretion in response to a change of tissue insulin sensitivity. In cold...
Normal glucose homeostasis depends on the capacity of pancreatic β-cells to adjust insulin secretion in response to a change of tissue insulin sensitivity. In cold environments, for example, the dramatic increase of insulin sensitivity required to ensure a sufficient supply of glucose to thermogenic tissues is offset by a proportionate reduction of insulin secretion, such that overall glucose tolerance is preserved. That these cold-induced changes of insulin secretion and insulin sensitivity are dependent on sympathetic nervous system (SNS) outflow suggests a key role for thermoregulatory neurons in the hypothalamic preoptic area (POA) in this metabolic response. As these POA neurons are themselves sensitive to changes in local hypothalamic temperature, we hypothesized that direct cooling of the POA would elicit the same glucoregulatory responses that we observed during cold exposure. To test this hypothesis, we used a thermode to cool the POA area, and found that as predicted, short-term (8-h) intense POA cooling reduced glucose-stimulated insulin secretion (GSIS), yet glucose tolerance remained unchanged due to an increase of insulin sensitivity. Longer-term (24-h), more moderate POA cooling, however, failed to inhibit GSIS and improved glucose tolerance, an effect associated with hyperthermia and activation of the hypothalamic-pituitary-adrenal axis, indicative of a stress response. Taken together, these findings suggest that POA cooling is sufficient to recapitulate key glucoregulatory responses to cold exposure.
Topics: Animals; Blood Glucose; Body Temperature Regulation; Glucose; Homeostasis; Insulin; Insulin Resistance; Male; Neurons; Preoptic Area; Rats, Wistar
PubMed: 30610874
DOI: 10.1016/j.brainres.2019.01.002 -
Annals of Anatomy = Anatomischer... Oct 2023Decreased estrogen levels can cause abnormal thermosensitivity of the preoptic area (POA) in the hypothalamus during menopause, which may cause hot flashes....
BACKGROUND
Decreased estrogen levels can cause abnormal thermosensitivity of the preoptic area (POA) in the hypothalamus during menopause, which may cause hot flashes. Thermosensitive transient receptors (ThermoTRPs) affect the thermosensitivity of neurons. It is worth exploring whether ThermoTRPs change under low estrogen state and participate in the abnormal thermoregulation of POA.
METHODS
Adult female Sprague-Dawley rats were randomly divided into sham operation (SHAM), ovariectomy (OVX) and estrogen treatment after ovariectomy (OVX+E) groups. Under 10 ℃, 18 ℃, 25 ℃, 37 ℃ and 45 ℃ incubations, their skin temperature was monitored and the expression of TRPA1, TRPM8, TRPM2, and TRPV1 in POA were investigated.
RESULTS
The skin temperature of ovariectomized rats changed faster and more dramatically under different incubation temperatures. The results at mRNA level show that only the expression of TRPM2 decreased in POA of OVX group compared with the other two groups at 25 ℃, TRPA1 expression in POA of the three groups increased at 10 ℃, TRPM8 increased at 10 ℃ and 18 ℃, TRPV1 increased at 10 ℃ and 45 ℃, while the expression of TRPM2 decreased at 10 ℃ and 18 ℃ and increased at 37 ℃ and 45 ℃. In all these cases, the magnitudes of the changes were less in the OVX group relative to the other two groups. The further immunohistochemical and Western blot results of TRPM2 and the activated TRPM2 positive cells labeled by c-Fos were consistent with the results of mRNA level.
CONCLUSIONS
The expression and thermosensitivity of TRPM2 in POA changed greatly under different incubation temperatures, but the changes in ovariectomized rats were less. This may be the key factor triggering thermoregulation dysfunction under low estrogen and may cause hot flashes.
Topics: Rats; Female; Animals; Humans; Preoptic Area; Hot Flashes; Rats, Sprague-Dawley; Transient Receptor Potential Channels; TRPM Cation Channels; Estradiol; Hypothalamus; Menopause; Estrogens; Body Temperature Regulation; RNA, Messenger; Ovariectomy
PubMed: 37454827
DOI: 10.1016/j.aanat.2023.152132 -
Neurochemical Research Oct 2019The behavior of female rats changes profoundly as they become mothers. The brain region that plays a central role in this regulation is the preoptic area, and lesions in...
The behavior of female rats changes profoundly as they become mothers. The brain region that plays a central role in this regulation is the preoptic area, and lesions in this area eliminates maternal behaviors in rodents. The molecular background of the behavioral changes has not been established yet; therefore, in the present study, we applied proteomics to compare protein level changes associated with maternal care in the rat preoptic area. Using 2-dimensional fluorescence gel electrophoresis followed by identification of altered spots with mass spectrometry, 12 proteins were found to be significantly increased, and 6 proteins showed a significantly reduced level in mothers. These results show some similarities with a previous proteomics study of the maternal medial prefrontal cortex and genomics approaches applied to the preoptic area. Gene ontological analysis suggested that most altered proteins are involved in glucose metabolism and neuroplasticity. These proteins may support the maintenance of increased neuronal activity in the preoptic area, and morphological changes in preoptic neuronal circuits are known to take place in mothers. An increase in the level of alpha-crystallin B chain (Cryab) was confirmed by Western blotting. This small heat shock protein may also contribute to maintaining the increased activity of preoptic neurons by stabilizing protein structures. Common regulator and target analysis of the altered proteins suggested a role of prolactin in the molecular changes in the preoptic area. These results first identified the protein level changes in the maternal preoptic area. The altered proteins contribute to the maintenance of maternal behaviors and may also be relevant to postpartum depression, which can occur as a molecular level maladaptation to motherhood.
Topics: Animals; Behavior, Animal; Electrophoresis, Gel, Two-Dimensional; Female; Maternal Behavior; Neurons; Prefrontal Cortex; Preoptic Area; Proteomics; Rats
PubMed: 30847857
DOI: 10.1007/s11064-019-02755-y -
Journal of Neuroendocrinology Jan 2020In male songbirds, song functions to attract a mate or to defend a territory; it is therefore often produced in the context of reproduction. Testosterone of gonadal... (Review)
Review
In male songbirds, song functions to attract a mate or to defend a territory; it is therefore often produced in the context of reproduction. Testosterone of gonadal origin increases during the reproductive phase of the annual cycle and significantly enhances song production, as well as song development, via effects on song crystallisation. The neural control of birdsong production and learning is highly modular. We implanted testosterone or androgen antagonists into specific brain regions or in the periphery of castrated male canaries and, in this way, identified how androgen signalling in specific locations regulates a variety of birdsong features. For example, castrated male canaries treated with testosterone in the preoptic area only and exposed to long days sing at high rates compared to castrated male canaries not treated with testosterone. However, these birds with testosterone in the preoptic area still produce songs with substantially lower song stereotypy and amplitude; these features are controlled by testosterone acting in the song control nuclei HVC and robust nucleus of the arcopallium. Specific aspects of the learned singing behaviour are thus regulated by androgens acting at multiple levels in the brain in a non-redundant fashion. The action of testosterone in the preoptic area is related to the hormonal regulation of the motivation to sing but not to various aspects of song performance. Multiple aspects of song quality are instead precisely regulated by steroids acting in distinct song control nuclei. Females exert a strong choice for specific features of male song in canaries and this choice is influenced by the endocrine state of the female. The female song system is also involved in song production, as well as song perception, although the specificity of this hormone action has not yet been investigated.
Topics: Androgen Receptor Antagonists; Animals; Preoptic Area; Signal Transduction; Songbirds; Testosterone; Vocalization, Animal
PubMed: 31514252
DOI: 10.1111/jne.12793 -
Hormones and Behavior Jul 2017Since Arnold Adolph Berthold established in 1849 the critical role of the testes in the activation of male sexual behavior, intensive research has identified many... (Review)
Review
Since Arnold Adolph Berthold established in 1849 the critical role of the testes in the activation of male sexual behavior, intensive research has identified many sophisticated neurochemical and molecular mechanisms mediating this action. Studies in Japanese quail demonstrated the critical role of testosterone action and of testosterone aromatization in the sexually dimorphic medial preoptic nucleus in the activation of male copulatory behavior. The development of an immunohistochemical visualization of brain aromatase in quail then allowed further refinement in the localization of the sites of neuroestrogens production. Testosterone aromatization is required for the activation of both appetitive and consummatory aspects of male sexual behavior. Brain aromatase activity is modulated by steroid-induced changes in the transcription of the corresponding gene but also more rapidly by phosphorylation processes. Sexual interactions with a female also rapidly regulate brain aromatase activity in an anatomically specific manner presumably via the release and action of endogenous glutamate. These rapid changes in estrogen production modulate sexual behavior and in particular its motivational component with latencies ranging between 15 and 30min. Brain estrogens seem to act in a manner akin to a neurotransmitter or at least a neuromodulator. More recently, assays of brain estradiol concentrations in micropunched samples or in dialysis samples obtained from behaviorally active males suggested that aromatase activity measured ex vivo might not be an accurate proxy to the rapid changes in local neuroestrogens production and concentrations. Studies of brain testosterone metabolism are thus not over and will keep scientists busy for a little longer. Elsevier SBN Keynote Address, Montreal.
Topics: Animals; Aromatase; Brain; Coturnix; Estrogen Receptor beta; Estrogens; Female; Humans; Male; Masculinity; Models, Animal; Preoptic Area; Sexual Behavior; Social Behavior; Testosterone
PubMed: 28576650
DOI: 10.1016/j.yhbeh.2017.05.017 -
Hormones and Behavior Sep 2021Corticotropin-releasing factor (CRF) signaling through CRF receptor 1 (CRFR1) regulates autonomic, endocrine, and behavioral responses to stress, as well as behavioral...
Corticotropin-releasing factor (CRF) signaling through CRF receptor 1 (CRFR1) regulates autonomic, endocrine, and behavioral responses to stress, as well as behavioral changes during the maternal period. Previous work in our lab reported higher levels of CRFR1 in female, compared to male, mice within the rostral anteroventral periventricular nucleus (AVPV/PeN), a brain region involved in maternal behaviors. In this study, we used CRFR1-GFP reporter mice to investigate whether the reproductive status (postpartum vs. nulliparous) of acutely stressed females affects levels of CRFR1 in the AVPV/PeN and other regions involved in maternal functions. Compared to nulliparous, postpartum day 14 females showed increased AVPV/PeN CRFR1-GFP immunoreactivity and an elevated number of restraint stress-activated AVPV/PeN CRFR1 cells as assessed by immunohistochemical co-localization of CRFR1-GFP and phosphorylated CREB (pCREB). The medial preoptic area (MPOA) and paraventricular hypothalamus (PVN) of postpartum mice showed modest decreases in CRFR1-GFP immunoreactivity, while increased CRFR1-GFP/pCREB co-expressing cells were found in the PVN following restraint stress relative to nulliparous mice. Tyrosine hydroxylase (TH) and CRFR1-GFP co-localization was also assessed in the AVPV/PeN and other regions and revealed a decrease in co-localized neurons in the AVPV/PeN and ventral tegmental area of postpartum mice. Corticosterone analysis of restrained mice revealed blunted peak, but elevated recovery, levels in postpartum compared to nulliparous mice. Finally, we investigated projection patterns of AVPV/PeN CRFR1 neurons using female CRFR1-Cre mice and revealed dense efferent projections to several preoptic, hypothalamic, and hindbrain regions known to control stress-associated and maternal functions. Together, these findings contribute to our understanding of the neurobiology that might underlie changes in stress-related functions during the postpartum period.
Topics: Animals; Corticotropin-Releasing Hormone; Female; Humans; Hypothalamus; Male; Mice; Postpartum Period; Preoptic Area; Receptors, Corticotropin-Releasing Hormone
PubMed: 34507241
DOI: 10.1016/j.yhbeh.2021.105044 -
Frontiers in Neuroendocrinology Oct 2021Male sexual behavior is subject to learning, resulting in increased efficiency of experienced males compared to naive ones. The improvement in behavioral parameters is... (Review)
Review
Male sexual behavior is subject to learning, resulting in increased efficiency of experienced males compared to naive ones. The improvement in behavioral parameters is underpinned by cellular and molecular changes in the neural circuit controlling sexual behavior, particularly in the hypothalamic medial preoptic area. This review provides an update on the mechanisms related to the sexual experience in male rodents, emphasizing the differences between rats and mice.
Topics: Animals; Hypothalamus; Male; Mice; Preoptic Area; Rats; Sexual Behavior, Animal
PubMed: 34687674
DOI: 10.1016/j.yfrne.2021.100949 -
Cell Metabolism Jul 2021The preoptic area (POA) is a key brain region for regulation of body temperature (Tb), dictating thermogenic, cardiovascular, and behavioral responses that control Tb....
The preoptic area (POA) is a key brain region for regulation of body temperature (Tb), dictating thermogenic, cardiovascular, and behavioral responses that control Tb. Previously characterized POA neuronal populations all reduced Tb when activated. Using mice, we now identify POA neurons expressing bombesin-like receptor 3 (POA) as a population whose activation increased Tb; inversely, acute inhibition of these neurons reduced Tb. POA neurons that project to either the paraventricular nucleus of the hypothalamus or the dorsomedial hypothalamus increased Tb, heart rate, and blood pressure via the sympathetic nervous system. Long-term inactivation of POA neurons caused increased Tb variability, overshooting both increases and decreases in Tb set point, with RNA expression profiles suggesting multiple types of POA neurons. Thus, POA neuronal populations regulate Tb and heart rate, contribute to cold defense, and fine-tune feedback control of Tb. These findings advance understanding of homeothermy, a defining feature of mammalian biology.
Topics: Animals; Body Temperature; Body Temperature Regulation; Heart Rate; Male; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Mice, Transgenic; Neurons; Preoptic Area; Receptors, Bombesin; Signal Transduction; Sympathetic Nervous System; Thermogenesis
PubMed: 34038711
DOI: 10.1016/j.cmet.2021.05.001