Regional specificity of gamma-aminobutyric acid receptor regulation by estradiol

In vitro quantitative autoradiography and the microdissection technique of Palkovitz were used to examine the effects of estradiol-17 beta on GABAA receptors and on glutamic acid decarboxylase in discrete areas of rat brain. Under the conditions examined, estradiol did not affect glutamic acid decarboxylase activity. However, treatment with estradiol decreased GABAA receptor binding in a majority of areas that contain high levels of intracellular estradiol receptors and in a number of areas that contain few or no estradiol receptors. Within one brain area, the ventromedial nucleus of the hypothalamus, the estradiol effect was mapped and found to occur within the estradiol-sensitive ventrolateral portion and the surrounding dendritic plexus. Time- and dose-response relationships were region specific suggesting that estradiol might influence GABAA-receptor binding through multiple mechanisms. Estradiol does not appear to interact directly with GABAA receptors since addition of estradiol to the assay system did not affect binding. Our findings suggest that one way estradiol might affect neuroendocrine and other centrally mediated processes is through effects on GABAA-receptor binding.     

Alpha 1-noradrenergic receptor blockade decreases nuclear estrogen receptor binding in guinea pig hypothalamus and preoptic area

Prazosin, a putative alpha 1-noradrenergic antagonist, reduced nuclear estrogen receptor levels in the hypothalamus and preoptic area of the estrogen-primed guinea pig. Noradrenergic transmission may alter steroid-dependent processes and neuroendocrine function through actions on steroid-concentrating cells.     

Randomized controlled trial of a brief intervention for increasing participation in parent management training

Evidence-based treatments exist for a range of child and adolescent behavior problems; however, effects are often limited by poor treatment attendance and adherence. The authors developed and evaluated the efficacy of a brief (5 to 45 min) intervention designed to increase treatment attendance and adherence in a sample of 76 parents referred for treatment of their child's oppositional, aggressive, and antisocial behavior. The results of this randomized controlled trial showed that parents who received this brief intervention had greater treatment motivation, attended significantly more treatment sessions, and had greater adherence to treatment according to both parent and therapist report. This study provides researchers and clinicians with a brief and efficacious method of increasing motivation, attendance, and adherence for treatment.     

Relationship of the ventilatory response to hypoxia with neonatal apnea in preterm infants

OBJECTIVE: Correlate the ventilatory response of preterm infants to hypoxic exposure with incidence of neonatal apnea.Study design Seventeen stable convalescing premature infants underwent bedside cardiorespiratory monitoring of respiration using respiratory inductance plethysmography, heart rate, and oxygen saturation (SaO(2)) for a 12-hour period. These studies were scored for number of apneas > or =15 and > or =20 seconds. Infants then underwent a 3-minute hypoxic exposure. Minute ventilation (V(E)) was calculated for 30-second epochs from the time inspired oxygen reached 15%. Linear regression analysis was used to correlate the change in V(E) normalized for decrease in SaO(2) (DeltaV(E)/DeltaSaO(2)) during the first and third minutes of hypoxic exposure with the number of apneic episodes during the 12-hour study. RESULTS: The majority of infants exhibited an anticipated biphasic ventilatory response to hypoxia. There was a significant positive correlation between DeltaV(E)/DeltaSaO(2) during the first and third minutes of hypoxic exposure and number of apneic episodes > or =15 and > or =20 seconds during the preceding 12 hours. CONCLUSIONS: Preterm infants with a greater number of apneic episodes exhibit an increased ventilatory response to hypoxic exposure, suggesting that apnea of prematurity may be associated with enhanced peripheral chemoreceptor activity.