Reduced Luteinizing Hormone Induction Following Estrogen and Progesterone Priming in Female-to-Male Transsexuals.

Anatomical studies have suggested that one of the brain structures involved in gender identity is the bed nucleus of the stria terminalis, though this brain structure is probably not the only one to control gender identity. We hypothesized that, if this brain area also affected gonadotropin secretion in humans, transsexual individuals might produce different gonadotropin levels in response to exogenous stimulation. In the present study, we examined whether estrogen combined with progesterone might lead to a change in luteinizing hormone (LH) secretion in female-to-male (FTM) transsexual individuals.

Sex differences in feeding behavior in rats: the relationship with neuronal activation in the hypothalamus.

There is general agreement that the central nervous system in rodents differs between sexes due to the presence of gonadal steroid hormone during differentiation. Sex differences in feeding seem to occur among species, and responses to fasting (i.e.

Expression of phosphorylated cyclic AMP response element-binding protein in melanin-concentrating hormone neurons and orexin neurons in male and female rats during ad-libitum feeding.

Using phosphorylated cyclic AMP response element-binding protein (pCREB) as a marker of neural activity, we previously suggested that orexin neurons and melanin-concentrating hormone (MCH) neurons play distinct roles in feeding behavior. In the present study, we examined the expression of pCREB during ad-libitum feeding; previously, only fasted animals were examined. MCH neurons, but not orexin neurons, expressed pCREB during spontaneous food intake.

Developmental trajectory of contextual learning and 24-h acetylcholine release in the hippocampus.

To determine the developmental trajectory of hippocampal function in rats, we examined 24-h changes in extracellular acetylcholine (ACh) levels and contextual learning performance. Extracellular ACh significantly correlated with spontaneous behavior, exhibiting a 24-h rhythm in juvenile (4-week-old), pubertal (6-week-old), and adult (9- to 12-week-old) rats. Although juveniles of both sexes exhibited low ACh levels, adult males had higher ACh levels than adult females.

Phosphorylation of cAMP response element-binding protein in the extended amygdala of male rats is induced by novel environment and attenuated by estrous female-bedding.

Objective: We examined whether female pheromone, which would be contained in female-soiled bedding, affected the expression of phosphorylated cAMP response element-binding protein-like (pCREB) immunoreactive cells in the extended amygdala.

Methods: Male rats were exposed to following conditions: maintained in their home cage (home cage group), or relocated to a cage containing clean bedding (clean-bedding exposed group), ovariectomized (OVX) rat-soiled bedding (OVX-bedding exposed group) or estrogen-treated OVX rat-soiled bedding (OVX+E2-bedding exposed group). Rats were sacrificed 10-20 min after exposure and brain sections were subject to immunocytochemical processing.

Sex-specific differences in pain response by dopamine in the bed nucleus of the stria terminalis in rats.

The formalin test for nociception shows characteristic sex differences in the pain response during the interphase period of the test. However, the mechanism underlying these differences remains unclear. We have recently reported the sex-specific involvement of the lateral subdivision of the bed nucleus of the stria terminalis (BSTL) in the formalin test in rats.

Testosterone exposure during the critical period decreases corticotropin-releasing hormone-immunoreactive neurons in the bed nucleus of the stria terminalis of female rats.

We previously described sex differences in the number of corticotropin-releasing hormone-immunoreactive (CRH-ir) neurons in the dorsolateral division of the bed nucleus of the stria terminalis (BSTLD). Female rats were found to have more CRH neurons than male rats. We hypothesized that testosterone exposure during the critical period of sexual differentiation of the brain decreased the number of CRH-ir neurons in the hypothalamus, including the BSTLD and preoptic area.

Progesterone receptor immunoreactivity in the brains of ovariectomized aged rats.

We examined the induction of progesterone receptor-immunoreactive (PR-ir) cells by estrogen in the rat preoptic area and ventromedial hypothalamic nucleus. Ovariectomized young (3-month-old) and old (24-month-old) female rats were treated with estrogen or cholesterol for 4 days. Estrogen significantly increased PR-ir cells in the preoptic area and ventromedial hypothalamic nucleus in young rats.

Formalin-induced nociceptive behavior and c-Fos expression in middle-aged female rats.

The impact of the estrous cycle on the nociceptive response in middle-aged female rats was assessed using the formalin test and c-Fos immunoreactivity as a marker of neural activation. Young (2-month-old) and middle-aged (11-month-old) rats were examined, dividing the middle-aged rats into two groups based on their estrous cycle: regular 4-day estrous cycle and irregular estrous cycle. The right hind paw was subcutaneously injected with 50microl of 2% formalin or saline as a control.

Age- and sex-specific changes in naloxone-induced luteinizing hormone secretion and Fos expression in gonadotropin-releasing hormone neurons of gonadectomized rats.

In the present study, we examined sex-specific changes in luteinizing hormone (LH) secretion and Fos expression in gonadotropin-releasing hormone (GnRH) neurons in response to naloxone in young (3 months old) and old (24 months old), gonadectomized male and female rats. We revealed by immunocytochemistry that, regardless of age and sex, naloxone significantly increased the number of GnRH neurons expressing Fos, which was associated with increased LH secretion. Additionally, although the magnitude of the increase in Fos-expressing GnRH neurons did not change in old males compared to young males, it was attenuated by almost half in old females compared to young females.

The cAMP response element-binding protein in the bed nucleus of the stria terminalis modulates the formalin-induced pain behavior in the female rat.

Abstract Differences in male and female responses to pain are widely recognized in many species, including humans, but the cerebral mechanisms that generate these responses are unknown. Using the formalin test, we confirmed that proestrus female rats showed nociceptive behavior, modulated by estrogen that was distinct from male rats, particularly during the interphase period. We then explored the brain areas, which were involved in the female pattern of nociceptive behavior.

Food availability affects orexin a/ hypocretin-1-induced inhibition of pulsatile luteinizing hormone secretion in female rats.

Orexin A/hypocretin-1 inhibits pulsatile luteinizing hormone (LH) secretion in female rats. In this study, we investigated whether this inhibition was tied to the fasting state, as suggested by our previous study. We first examined whether orexin A inhibited pulsatile LH secretion when food was available ad libitumduring blood sampling.

Sex differences in the responses of orexin neurons in the lateral hypothalamic area and feeding behavior to fasting.

Because there are sex differences in feeding-related behavior and orexin neurons are involved in feeding, we looked for a possible sex difference in the response of orexin neurons in the lateral hypothalamic area to fasting, using the phosphorylated cyclic AMP response element-binding protein (pCREB) as a marker of neural activity. Intact male and female rats at proestrus, estrus, or diestrus, were fed normally or fasted for 48h. After fasting, they were intravenously injected with saline or glucose and subjected to immunohistochemical processing for the detection of orexin and pCREB.

Sex-specific 24-h profile of extracellular serotonin levels in the medial prefrontal cortex.

The medial prefrontal cortex (mPFC) controls emotional responses in many species,receiving serotonergic innervation from the dorsal and median raphe nucleus (DRN and MRN). To examine the sex difference in 24-h profiles of extracellular serotonin (5HT) levels in the mPFC, an in vivo microdialysis study was performed using intact male, diestrous female, and proestrous female rats. Dialysates were automatically collected by a microdialysis probe from the mPFC every 30 min for more than 24 h under freely moving conditions.

Gonadal steroids maintain 24 h acetylcholine release in the hippocampus: organizational and activational effects in behaving rats.

Extracellular acetylcholine (ACh) levels in the dorsal hippocampus increases during learning or exploration, exhibiting a sex-specific 24 h release profile. To examine the activational effect of gonadal steroid hormones on the sex-specific ACh levels and its correlation with spontaneous locomotor activity, we observed these parameters simultaneously for 24 h. Gonadectomy severely attenuated the ACh levels, whereas the testosterone replacement in gonadectomized males or 17beta-estradiol replacement in gonadectomized females successfully restored the levels.

Symptom prevalence and longitudinal follow-up in cancer outpatients receiving chemotherapy.

Palliative care for cancer patients receiving chemotherapy in the outpatient setting is important. The aims of this study were 1) to identify symptom prevalence and intensity in cancer patients receiving chemotherapy and 2) to describe longitudinal follow-up data obtained from repeated assessment using the distress thermometer (DT). Questionnaires were distributed to consecutive cancer outpatients newly starting chemotherapy at the first appointment and at every hospital visit.

Postpubertal feeding experience affects sex-specific spatial ability in rats.

We previously reported that feeding with powdered diet after weaning (3 weeks of age) enhanced spatial ability, and increased the amount of acetylcholine (ACh) released in the dorsal hippocampus in female rats. In the present study, to specify the time when feeding conditions caused these effects, a radial 8-arm maze task and an in vivo microdialysis study were performed in both sexes of rats. In rats fed standard laboratory diet (i.

Gonadal steroid hormones maintain the stress-induced acetylcholine release in the hippocampus: simultaneous measurements of the extracellular acetylcholine and serum corticosterone levels in the same subjects.

To examine the role of gonadal steroid hormones in the stress responses of acetylcholine (ACh) levels in the hippocampus and serum corticosterone levels, we observed these parameters simultaneously in intact, gonadectomized, or gonadectomized steroid-primed rats. In both sexes of rats, neither gonadectomy nor the replacement of gonadal steroid hormone affected the baseline levels of ACh. However, gonadectomy severely attenuated the stress response of ACh, whereas the replacement of corresponding gonadal hormone successfully restored the response to intact levels.

Sex difference in the 24-h acetylcholine release profile in the premotor/supplementary motor area of behaving rats.

The sex differences in various motor functions suggest a sex-specific neural basis in the nonprimary or primary motor area. To examine the sex difference in the 24-h profile of acetylcholine (ACh) release in the rostral frontal cortex area 2 (rFr2), which is equivalent to the premotor/supplementary motor area in primates, we performed an in vivo microdialysis study in both sexes of rats fed pelleted or powdered diet. The dialysate was automatically collected from the rFr2 for 24 h under freely moving conditions.

Sex differences in the basolateral amygdala: the extracellular levels of serotonin and dopamine, and their responses to restraint stress in rats.

The sex difference in the emotional response to stress suggests a sex-specific stress response in the amygdala. To examine the sex difference in extracellular levels of serotonin (5HT) and dopamine (DA) in the basolateral amygdala (BLA) and their responses to restraint stress, in vivo microdialysis studies were performed in male and female rats. In experiment I, dialysates were collected from the BLA at 15-min intervals under the freely moving condition.

Effects of neonatal testosterone treatment on sex differences in formalin-induced nociceptive behavior in rats.

There are sex differences in nociceptive behavior induced by formalin in rats. To determine whether these sex differences are the result of the sexual differentiation of the brain, that is masculinization and defeminization [A.P.

Bisphenol A induces transforming growth factor-beta3 mRNA in the preoptic area: a cDNA expression array and Northern blot study.

To gain better understanding of the effects of bisphenol A (BPA) in the adult brain, a cDNA expression array was used to screen possible candidates for BPA-inducible genes in the medial preoptic area (MPOA). Adult ovariectomized rats were given a subcutaneous injection of 10 mg BPA or sesame oil alone as a control. Twenty-four hours after the injection, the MPOAs were dissected and total RNAs were extracted.

Effects of p-nonylphenol and 4-tert-octylphenol on the anterior pituitary functions in adult ovariectomized rats.

p-Nonylphenol (NP) and 4-tert-octylphenol (OP) are known to mimic the action of estrogens as endocrine disruptors. However, their acute effects on the pituitary and the hypothalamus functions in vivo have been uncertain. We therefore determined their effects on the anterior pituitary, in particular, gonadotropin secretion.