Behavioral sensitization: Characterization of enduring changes in rotational behavior produced by intermittent injections of amphetamine in male and female rats

Factors influencing the behavioral sensitization (reverse tolerance) produced by intermittent amphetamine (AMPH) injections were studied by quantifying rotational behavior in rats that had a unilateral 6-hydroxydopamine lesion of the substantia nigra. The results indicate that (1) a single injection of a low dose of AMPH enhances rotational behavior induced by a second injection of AMPH for up to 12 weeks; (2) multiple, weekly injections of AMPH produce a progressive enhancement in rotational behavior, over-and-above that produced by a single injection; (3) female rats show more robust sensitization than males following single or multiple injections of AMPH; (4) this sex difference may be due to the suppression of sensitization by an androgen, because removal of testicular hormones potentiates sensitization; (5) the long-lasting sensitization of rotational behavior produced by infrequent injections of AMPH is not due to drug-environment conditioning effects, but perhaps to a persistent AMPH-induced change(s) in brain catecholamine systems; and (6) a simple change in DA receptors is probably no involved, because the sensitization produced by infrequent injections of AMPH does not influence the rotation produced by a subsequent injection of apomorphine. The results illustrate an intriguing example of neuroplasticity that may have clinical relevance.     

Pubertal development in thalassaemic patients after allogenic bone marrow transplantation

To obtain further insight into gonadal function, a series of 50 prepubertal patients with -thalassaemia major (24 boys and 26 girls) aged from 12.6 to 18 years (mean 15 years) who had received a bone marrow transplantation (BMT) during childhood or the peripubertal period, at the age of 3.6–14.5 years (mean 10.8 years), were periodically re-evaluated at intervals of 6–12 months. The last evaluation was done 1–9 years (mean 4.2 years) after BMT. At each examination we measured height, pubertal stage, plasma gonadotrophins (LH and FSH) before and after the GnRH stimulation test (i.v.), sex steroids (total and free testosterone in males, and 17-oestradiol in females), serum ferritin and bone age. Fourty percent of patients entered or passed through puberty normally despite clinical and hormonal evidence of gonadal dysfunction in most of them. A correlation was not found between the pubertal stage and age at BMT, and no statistical difference between patients who did not enter into puberty and patients with spontaneous pubertal development was found in serum ferritin levels. Our data confirm that gonads in male and female thalassaemic patients are exposed to the cytotoxic effects of the preparative transplant regime with alkylating agents. In some patients absence of pubertal development was due to gonadotrophin insufficiency, probably secondary to previous iron overload. These findings emphasize the need for a vigilant long-term follow up study of thalassaemic patients who have had BMT.Part of this work has been presented at the 2nd International Symposium on Bone Marrow Transplantation in Thalassemia. Pesaro, Italy, 1992 and was supported by A.I.L., Pesaro, Italy.     

Relationships between oral MUC1 expression and salivary hormones in burning mouth syndrome

ObjectivesTo investigate possible relationships among oral mucosal epithelial MUC1 expression, salivary female gonadal hormones and stress markers, and clinical characteristics in patients with burning mouth syndrome (BMS).DesignThirty post-menopausal female patients with BMS (60.0 ± 5.0 years) were included. Clinical and psychological evaluations were performed and the expression level of oral mucosal epithelial MUC1 was analyzed. The levels of cortisol, dehydroepiandrosterone (DHEA), 17β-estradiol, progesterone, chromogranin A, and blood contamination were determined from unstimulated whole saliva (UWS) and stimulated whole saliva (SWS) samples.ResultsSalivary progesterone level had significant positive correlations with oral mucosal epithelial MUC1 expression level and with salivary cortisol and DHEA levels. The salivary level of 17β-estradiol showed significant positive correlations with period of symptom duration, severity of effects of oral complaints on daily life, and results from psychological evaluations. Cortisol level in UWS and cortisol/DHEA ratio in UWS and SWS had negative correlations with severity of oral burning sensation significantly. The severity of taste disturbance had positive correlations with results from psychometry significantly.ConclusionDysregulated psychoendocrinological interactions might affect oral mucosal MUC1 expression and severity of oral burning sensation in post-menopausal BMS patients.     

Estrogenic influences in pain processing

Gonadal hormones not only play a pivotal role in reproductive behavior and sexual differentiation, they also contribute to thermoregulation, feeding, memory, neuronal survival, and the perception of somatosensory stimuli. Numerous studies on both animals and human subjects have also demonstrated the potential effects of gonadal hormones, such as estrogens, on pain transmission. These effects most likely involve multiple neuroanatomical circuits as well as diverse neurochemical systems and they therefore need to be evaluated specifically to determine the localization and intrinsic characteristics of the neurons engaged. The aim of this review is to summarize the morphological as well as biochemical evidence in support for gonadal hormone modulation of nociceptive processing, with particular focus on estrogens and spinal cord mechanisms.     

Fluidity models in ancient Greece and current practices of sex assignment

Disorders of sexual differentiation such as androgen insensitivity and gonadal dysgenesis can involve an intrinsic fluidity at different levels, from the anatomical and biological to the social (gender) that must be considered in the context of social constraints. Sex assignment models based on George Engel’s biopsychosocial aspects model of biology accept fluidity of gender as a central concept and therefore help establish expectations within the uncertainty of sex assignment and anticipate potential changes. The biology underlying the fluidity inherent to these disorders should be presented to parents at diagnosis, an approach that the gender medicine field should embrace as good practice. Greek mythology provides many accepted archetypes of change, and the ancient Greek appreciation of metamorphosis can be used as context with these patients. Our goal is to inform expertise and optimal approaches, knowing that this fluidity may eventually necessitate sex reassignment. Physicians should provide sex assignment education based on different components of sexual differentiation, prepare parents for future hormone-triggered changes in their children, and establish a sex-assignment algorithm.     

雄激素及其受体与老年男性冠状动脉粥样硬化性心脏病的相关性研究

目的 观察老年男性冠状动脉粥样硬化性心脏病(冠心病)患者性激素及雄激素受体水平的变化及相关性. 方法 横断面调查老年男性539例,其中健康人(对照组)400例,年龄62～92岁,平均(71.4±5.2)岁;冠心病患者139例,年龄60～88岁,平均(73.6±6.4)岁.测定总睾酮、游离睾酮、脱氢表雄酮硫酸酯(DHEAS)、性激素结合球蛋白(SHBG)、雌二醇、黄体生成素(LH)、卵泡刺激素(FSH)水平,同时采用流式细胞术检测外周血雄激素受体(AR)水平. 结果 老年男性冠心病患者DHAES、总睾酮、SHBG、游离睾酮、AR荧光强度均低于对照组(均为P<0.01),而FSH、E2高于对照组(均为P<0.01).年龄与总睾酮、游离睾酮呈负相关(r分别为-0.28、-0.17,P<0.01和P<0.05);与E2、SHBG呈正相关(r分别为0.33、0.14,P<0.01和P<0.05).AR荧光强度与收缩压呈负相关(r=-0.12,P<0.01).Logistic回归分析显示,总睾酮(OR=1.065,95%CI:1.012～1.121,P<0.05)、SHBG(OR=0.994,95%CI:0.990～0.998,P<0.01)和AR(OR=0.971,95%CI:0.956～0.986,P<0.01)与老年男性冠心病相关. 结论 老年男性冠心病患者存在低水平的DHEAS、总睾酮、SHBG、游离睾酮、AR,同时存在高水平的FSH、E2;低水平总睾酮、SHBG和AR可能是老年男性冠心病独立的危险因素.     

不同干预措施对青春期肥胖型PCOS患者性激素及其临床表现的影响

【目的】探讨不同干预措施对青春期肥胖型多囊卵巢综合征（PCOS ）患者性激素及其临床表现的影响。【方法】收集13～20岁青春期肥胖型PCOS患者127例,根据干预措施不同分为3组：A组（44例）,生活方式调整＋炔雌醇环丙孕酮（达英‐35）＋盐酸二甲双胍治疗;B组（42例）,仅用生活方式调整;C组（41例）,达英‐35＋盐酸二甲双胍治疗,均干预3个月,比较各组干预后性激素水平和临床指标。【结果】三组治疗后体质量指数（BMI）均有显著性下降（ P ＜0．05）,且A组BMI显著低于B组、C组（ P ＜0．05）,但B组与C组比较差异无统计学意义（ P ＞0．05）。A组与C组治疗后的黄体生成素／卵泡刺激素（LH／FSH）、睾酮（T）均有显著下降（ P ＜0．05）,B组治疗后LH／FSH、T 虽亦呈下降趋势,但与治疗前比较无显著性差异（ P ＞0．05）。三组治疗后月经异常改善明显,痤疮、多毛等改善不明显。【结论】生活方式调整联合达英‐35和盐酸二甲双胍通过降低PCOS患者BM I、L H／FS H及T水平,有效恢复月经,且其作用优于达英‐35和盐酸二甲双胍,但对多毛、痤疮等症状改善不明显。     

Sex differentiation and sex change in the protandrous black porgy, Acanthopagrus schlegeli

Protandrous black porgy fish, Acanthopagrus schlegeli, have a striking life cycle with a male sex differentiation at the juvenile stage and male-to-female sex change at 3 years of age. We had characterized the sex differentiation and sex change in this species by the integrative approaches of histology, endocrine and molecular genetics. The fish differentiated in gonad at the age around 4-months and the gonad further developed with a bisexual gonad for almost for 3 years and sex change at 3 year of age. An antagonistic relationship in the testicular and ovarian tissues was found during the development of the gonadal tissue. Male- (such as sf-1, dmrt1, dax-1 and amh) and female- (such as wnt4, foxl2 and cyp19a1a) promoting genes were associated with testicular and ovarian development, respectively. During gonadal sex differentiation, steroidogenic pathway and estrogen signaling were also highly expressed in the brain. The increased expression of sf-1 and wnt4, cyp19a1a in ovarian tissue and decreased expression of dax-1 in the ovarian tissue may play important roles in sex change from a male-to-female. Endocrine factors such as estradiol and luteinizing hormone may also involve in the natural sex change. Estradiol induced the expression of female-promoting genes and resulted in the precocious sex change in black porgy. Our series of studies shed light on the sex differentiation and sex change in protandrous black porgy and other animals.