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Sexual Hormones (sexual + hormones)
Selected AbstractsSex hormone-dependent desensitization of 5-HT1A autoreceptors in knockout mice deficient in the 5-HT transporterEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 8 2003Saoussen Bouali Abstract The serotonin transporter (5-HTT) is the target of most antidepressant drugs, whose therapeutic action is related to their facilitatory influence on 5-HT neurotransmission. In this study, we investigated the functional adaptive properties of 5-HT1A autoreceptors, which regulate serotonergic neuronal firing, in knockout mice deficient in 5-HTT. Neurons of the dorsal raphe nucleus (DRN) were recorded extracellularly under chloral hydrate anaesthesia in male and female knockout 5-HTT mice and their wild-type counterparts. The inhibitory response of DRN neurons to intravenous injection of the 5-HT1A agonist 8-OH-DPAT was dramatically reduced in knockout 5-HTT compared with wild-type mice, especially in females. Changes in 8-OH-DPAT-induced hypothermia and autoradiographic labelling of 5-HT1A sites in the DRN confirmed a greater level of desensitization/down-regulation of 5-HT1A autoreceptors in female than in male knockout 5-HTT mice. After gonadectomy, the functional status of 5-HT1A autoreceptors was unchanged in wild-type mice, whereas in knockout 5-HTT, castrated males exhibited a down-regulation, and ovariectomized females an up-regulation of these receptors, as shown by electrophysiological recording and autoradiographic labelling in the DRN, as well as by changes in 8-OH-DPAT-induced hypothermia. Finally, in gonadectomized knockout 5-HTT mice, treatment with testosterone or estradiol restored the DRN neuronal firing sensitivity to 8-OH-DPAT back to sham control level in males or females, respectively. These data indicate that sexual hormones participate in the mechanisms responsible for the desensitization of 5-HT1A autoreceptors in knockout 5-HTT mice. The differential effects of testosterone and estradiol on 5-HT1A -mediated control of 5-HT neurotransmission might be related to the well-established gender differences in the vulnerability to depression. [source] Sex differences in cerebral injury after severe haemorrhage and ventricular fibrillation in pigsACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 3 2010E. SEMENAS Background: Experimental studies of haemorrhagic shock have documented a superior haemodynamic response and a better outcome in female animals as compared with male controls. Such sexual dimorphism has, nevertheless, not been reported after circulatory arrest that follows exsanguination and shock. We aimed to study differences in cerebral injury markers after exsanguination cardiac arrest in pre-pubertal piglets. The hypothesis was that cerebral injury is less extensive in female animals, and that this difference is independent of sexual hormones or choice of resuscitative fluid. Methods: Thirty-two sexually immature piglets (14 males and 18 females) were subjected to 5 min of haemorrhagic shock followed by 2 min of ventricular fibrillation and 8 min of cardiopulmonary resuscitation, using three resuscitation fluid regimens (whole blood, hypertonic saline and dextran, or acetated Ringers' solution plus whole blood and methylene blue). Haemodynamic values, cellular markers of brain injury and brain histology were studied. Results: After successful resuscitation, female piglets had significantly greater cerebral cortical blood flow, tended to have lower S-100, values and a lower cerebral oxygen extraction ratio. Besides, in female animals, systemic and cerebral venous acidosis were mitigated. Female piglets exhibited a significantly smaller increase in neuronal nitric oxide synthase (nNOS) and inducible nitric oxide synthase (iNOS) expression in their cerebral cortex, smaller blood,brain-barrier (BBB) disruption and significantly smaller neuronal injury. Conclusion: After resuscitation from haemorrhagic circulatory arrest, cerebral reperfusion is greater, and BBB permeability and neuronal injury is smaller in female piglets. An increased cerebral cortical iNOS and nNOS expression in males implies a mechanistic relationship with post-resuscitation neuronal injury and warrants further investigation. [source] Sex Modulates the Arrhythmogenic Substrate in Prepubertal Rabbit Hearts with Long QT 2JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2005Ph.D., TONG LIU M.D. Females have a greater susceptibility to Torsade de Pointes in congenital and drug-induced long QT syndrome (LQTS) that has been attributed to the modulation of ion channel expression by sex hormones. However, little is known regarding sex differences in pre-puberty, that is, before the surge of sexual hormones. In patients with congenital LQTS types 1 and 2, male children tend to have a greater occurrence of adverse events, especially in 10,15 year olds, than their female counterpart. To evaluate whether the rabbit model of drug-acquired LQTS exhibits similar age dependences, hearts of prepubertal rabbits were perfused, mapped optically to record action potentials (APs) and treated with an IKr blocker, E4031 to elicit LQTS2. As expected, AP durations (APD) were significantly longer in female (n = 18) than male hearts (n = 10), at long cycle length. Surprisingly, E4031 (50,250 nM) induced a greater prolongation of APDs in male than in female hearts, and in both genders reversed the direction of repolarization (apex , base to base , apex), enhancing dispersions of repolarization. Furthermore, in male hearts, E4031 (0.5 ,M) elicited early afterdepolarizations (EADs) that progressed to polymorphic ventricular tachycardia (PVT) (n = 7/10) and were interrupted by isoproterenol (40 nM) and prevented by propranolol (0.5,2.5 ,M). In female hearts, E4031 (0.5 ,M) produced marked prolongations of APDs yet few EADs with no progression to PVT (n = 16/18). Thus, sex differences are opposite in prepubertal versus adult rabbits with respect to E4031-induced APD prolongation, EADs and PVT, underscoring the fact that APD prolongation alone is insufficient to predict arrhythmia susceptibility. [source] Influence of sex hormones on the periodontiumJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 8 2003Paulo Mascarenhas Abstract Objectives: Sex hormones have long been considered to play an influential role on periodontal tissues, bone turnover rate, wound healing and periodontal disease progression. The objectives of this review article are to (1) address the link between sex hormones and the periodontium, (2) analyse how these hormones influence the periodontium at different life times and (3) discuss the effects of hormone supplements/replacement on the periodontium. Materials and Methods: Two autonomous searches were performed in English language utilizing Medline, Premedline and Pubmed as the online databases. Publications up to 2002 were selected and further reviewed. In addition, a manual search was also performed including specific related journals and books. Results: It is certain that sexual hormones play a key role in periodontal disease progression and wound healing. More specifically, these effects seem to differentiate by gender as well as lifetime period. In addition, the influence of sex hormones can be minimized with good plaque control and with hormone replacement. Conclusion: Despite profound research linking periodontal condition with sex hormones kinetics, more definitive molecular mechanisms and therapy still remain to be determined. Zusammenfassung Männliche und weibliche Sexualhormone wurden schon lange einen wichtigen Einfluss auf das parodontale Gewebe, die Knochenumsatzrate, die Wundheilung und die parodontale Erkrankungsprogression ausübend betrachtet. Der Einfluss dieser Hormone auf das Parodontium unterscheidet sich zu verschiedenen physiologischen Phasen (z.B. Pubertät, Schwangerschaft, post Menopause) und mit der Einnahme von Pharmaka (z.B. Antikonzeptiva, Hormonsubstitution). Deshalb ist der Zweck dieses Reviewartikels (1) die Beziehung zwischen Sexualhormonen und dem Parodontium zu beschreiben, (2) die Analyse des Einflusses dieser Hormone auf das Parodontium zu unterschiedlichen Lebenszeiten und (3) die Effekte von Hormonunterstützung/substitution auf das Parodontium zu diskutieren. Résumé On a longtemps considéré que les hormones sexuelles, aussi bien masculines que féminines, jouaient un rôle important sur les tissus parodontaux, le taux de remaniement osseux, la cicatrisation et la progression de la maladie parodontale. L'influence de ces hormones sur le parodonte est différente en fonction des divers conditions physiologiques (par exemple, la puberté, la grossesse, et après la ménopause) et les prises de médicaments (par exemple, la pillule contraceptive et les traitements hormonaux de substitution). Aussi, cette revue critique de la littérature se propose (1) de faire le point sur les liens entre les hormones sexuelles et le parodonte (2) d' analyser la façon dont ces hormones influencent le parodonte lors des différentes étapes de la vie, et (3) discuter les effets des hormones de substitution sur le parodonte. [source] ORIGINAL RESEARCH: Prevalence and Evaluation of Sexual Health Problems,HSDD in EuropeTHE JOURNAL OF SEXUAL MEDICINE, Issue 2007Alessandra Graziottin MD ABSTRACT Introduction., The complex condition of the menopause is experienced by all women going through the physical and emotional changes associated with ovarian sexual hormones loss. It may impact directly on their physical and mental health. Aim., The complexity of this condition makes it necessary to accumulate large bodies of data to define the patterns and trends in its evaluable manifestations. To this end, large amounts of data were collected on women from France, Germany, Italy, and the United Kingdom, via the Women's International Survey on Health and Sexuality. Main Outcome Measures., The key measures within the survey were the Profile of Female of Sexual Function© (PFSF©) and the Personal Distress Scale© (PDS©). Results., The survey yielded 2,467 responders aged between 20 and 70, capturing women with surgical and natural menopausal status and those with premenopausal status. In the four EU countries studied, sexual activity decreases by age. An increase in female sexual dysfunction (FSD), particularly loss of sexual desire, is directly correlated with increasing age. However, the distress associated with loss of sexual desire is inversely correlated with age. Cultural and context-dependent factors modulate the percentage of any FSD in the different European countries. This is exemplified in the significant intercountry variation observed in the percentage of low desire in women aged 20,49, with normal ovarian function. However, when women undergo surgical menopause, with concomitant loss of their sexual hormones, the culture-related differences are blunted. Conclusions., The findings of this survey have implications for the understanding of hypoactive sexual desire disorder (HSDD), not only the way it should be assessed in clinical practice, but also the most appropriate means for its treatment. Testosterone deficiency is a significant cause of HSDD, and new therapies have been investigated which offer considerable potential to address this hormonal etiology. Graziottin A. Prevalence and evaluation of sexual health problems,HSDD in Europe. J Sex Med 2007;4(suppl 3):211,219. [source] | ||||||||||