Hypertension in the elderly. Which are the blood pressure threshold values?

Managing blood pressure is often difficult in the elderly, not only because of comorbidities, but also due to vascular remodelling and the changes in the renal and endocrine physiology. The structural and functional arterial modifications lead to impaired vessel’s compliance and increased systolic blood pressure (SBP), often with reduction of diastolic blood pressure (DBP)

Update on male reproductive endocrinology.

Practitioners of male reproductive and sexual medicine must have an intimate understanding of the physiology of male reproductive endocrinology, as such a knowledge is the cornerstone on which hormonal treatments are based. In this review, we highlight what is known about male reproductive endocrine physiology and the various control mechanisms for the system. We also discuss the limitations of our current understanding of the reproductive physiology. We hope that this review is helpful for male reproductive medicine practitioners in understanding the principles on which hormonal treatments are based

Early clinical exposure to first year medical students through case-based learning in endocrine physiology

Background:As per the Medical Council of India’s Vision-2015 document, coordinated inter-departmental efforts should be undertaken to provide early clinical exposure and to develop communication skills among medical students during the first year of Bachelor of Medicine, Bachelor of Surgery (MBBS) course. For this reason, this inter-departmental study was undertaken, to provide early clinical exposure while teaching endocrine physiology to first-year medical students. Case based learning (CBL) was used as an add-on to traditional didactic lectures (TDLs) for teaching endocrine physiology to first-year undergraduate medical students to compare the cognitive domain scores in pre CBL and post CBL tests.Methods: After getting permissions from the Institutional Ethics Committee (IEC) and other institutional authorities for conducting the study, the objectives of the study were explained to first year MBBS students. Written informed consent was taken from students (n=59) who were willing to participate in the study. After delivering regular TDLs on endocrine physiology as per topics in the syllabus, a pre CBL test was conducted. Subsequently, the participating students were simultaneously exposed to case scenarios related to the endocrine system by the same facilitator. A post CBL test (identical to pre CBL test) was administered to compare the cognitive domain scores.Results: Statistically significant differences were found in the student wise and question wise scores in the pre and post tests.Conclusions: Early clinical exposure of a relatively larger batch of students to CBL by the same facilitator was found to increase cognitive domain scores.

Roles of connexins and pannexins in (neuro)endocrine physiology.

International audienceTo ensure appropriate secretion in response to organismal demand, (neuro)endocrine tissues liberate massive quantities of hormone, which act to coordinate and synchronize biological signals in distant secretory and non-secretory cell populations. Intercellular communication plays a central role in this control. With regard to molecular identity, junctional cell-cell communication is supported by connexin (Cx)-based gap junctions. In addition, connexin hemichannels, the structural precursors of gap junctions, as well as pannexin (Panx) channels have recently emerged as possible modulators of the secretory process. This review focuses on the expression of connexins and pannexins in various (neuro)endocrine tissues, including the adrenal cortex and medulla, the anterior pituitary, the endocrine hypothalamus and the pineal, thyroid and parathyroid glands. In response to a physiological or pathological situation, junctional intercellular coupling can be acutely modulated or persistently remodelled, thus offering multiple regulatory possibilities. The functional role(s) of gap junction-mediated intercellular communication in endocrine physiology, as well as the involvement of connexin/pannexin-related hemichannels are also discussed

The Effects of Acoustic Signals on the Endocrine Physiology of Female Green Treefrogs, Hyla Cinerea

The vocalizations of male H. cinerea stimulate cortisol production in male receivers during close-range interactions. In many vertebrate species, males and females possess similar sensory neuroendocrine pathways, suggesting that acoustic signals may also stimulate CORT production in females. Males of this species would potentially benefit from stimulating CORT production in females because elevated CORT levels significantly decrease the strength of female preferences for energetically costly calls (i.e., calls produced at rapid rates). The primary objective of my honors research was to assess how the acoustic signals produced by male green treefrogs, Hyla cinerea, influence the endocrine physiology of female signal receivers. Specifically, I assessed how male acoustic signals alter circulating levels of stress hormones (i.e., glucocorticoids) in females. My results were unexpected in that advertisement calls actually decreased circulating levels of CORT in female receivers, indicating that males do not manipulate the stress physiology of females in ways that would allow them to gain access to females. My research thus suggests that there are neuroendocrinological differences between males and females that result in very different endocrine responses to the same acoustic signals. Another interesting outcome that emerged from my data involved the effect of aggressive calls on the endocrine physiology of females. Results indicated that exposure to aggressive calls resulted in decreased levels of progesterone and a marginally significant reduction in estradiol. These results may explain why males of this species only use aggressive signals in the context of male-male interactions; female reception of aggressive calls would decrease hormones associated with female sexual behavior, and thus decreases the likelihood of reproductive success for calling males

Nonylphenol and octylphenol differently affect cell redox balance by modulating the nitric oxide signaling

Nonylphenol (NP) and octylphenol (OP) are pervasive environmental contaminants belonging to the broader class of compounds known as alkylphenols, with potential human toxic effects. Classified as "xenoestrogens," NP and OP are able to interfere with the cell endocrine physiology via a direct interaction with the estrogen receptors. Here, using HepG2 cells in culture, the changes of the cell redox balance and mitochondrial activity induced by OP and NP have been investigated at mu M concentrations, largely below those provoking acute toxicity, as those typical of environmental contaminants. Following 24 h cell exposure to both OP and NP, ROS production appeared significantly increased (p <= 0.01), together with the production of higher NO oxides (p = 0.003) and peroxynitrated protein-derivatives (NP versus CTR, p = 0.003). The mitochondrial proton electrochemical potential gradient instead was decreased (p <= 0.05), as the oxygen consumption by complex IV, particularly following incubation with NP (NP versus CTR, p = 0.017). Consistently, the RT-PCR and Western blot analyses proved that the OP and NP can modulate to a different extent the expression of the inducible NOS (NP versus CTR, p <= 0.01) and the endothelial NOS (OP versus CTR, p <= 0.05), with a significant variation of the coupling efficiency of the latter (NP versus CTR, p <= 0.05), a finding that may provide a novel clue to understand the specific xenoestrogenic properties of OP and NP

Hormone Receptor Site Maturation in the Secondary Sex Organs of Immature Male and Female Rats

The effect of a combined dose of pregnant mares\u27 serum (PAAS) and human chor ionic gonadotropin (HCG) on male and female rats 2-25 days old was studied. Groups of animals were given injections for three days, then sacrificed on the fourth day. All injections were begun on the 2nd, 7th, 12th, 17th, and 22nd day of life. Ovaries, uteri, seminal vesicles (SV), and ventral prostate (VP) were removed, dissected free of fat, and weighed. Because uterine weight increased earlier than either SV or VP weight, the ability of the uterus to respond to exogenous estradiol and of the SV and VP to respond to exogenous testosterone was examined. The injection schedule, age groups, and day of sacrifice were the same as above. The uterine response to estrogen was found to appear earlier than the VP-SV response totestosterone. The observations suggest that the receptor sites for estrogen may mature earlier than the receptor sites for testosterone