Endocrine Abstracts

Having been known as a reliable tool for assessing the Hypothalamus-Pituitary-Adrenal (HPA) axis, measurement of salivary cortisol plays an important role in both the clinical settings and the researches. To establish a normative data, which forms the basis for the usage of this valuable parameter, we gathered 8:00 h saliva samples from 94 healthy individuals aged 6-14 years. Cortisol levels were measured by radioimmunoassay technique, using Orion Diagnostica`s coated tube tec...

Increased severity of periodontal disease has been reported in post-menopausal oestrogen deficient subjects, made worse by smoking. It was relevant to investigate this concept, using fibroblasts in culture and extrapolating the yields of androgen metabolites as an index of healing. The aim of this study is to establish the effects of nicotine (N), oestradiol (O) and the alkaline phosphatase inhibitor levamisole (L) on androgen metabolism in human gingival fibroblasts in this c...

Glucocorticoids modulate the effects of other hormones and also mediate cell function. Dexamethasone, in common with androgen metabolites, has been shown to increase alkaline phosphatase activity and bone specific marker proteins The aim of this investigation is to establish an androgen responsive element to dexamethasone as an index of regenerative potential in the periodontium, using the alkaline phosphatase inhibitor levamisole (L). 4 cell lines of oral periosteal fibroblas...

The aim of this investigation is to establish the effect of alkaline phosphatase on androgen metabolism in human gingival fibroblasts (obtained local Ethical Committee approval) and its possible mediation by the alkaline phosphatase inhibitor levamisole and nicotine, using radiolabelled testosterone as substrate. Monolayer cultures of fibroblasts were established in Eagle's MEM. Duplicate incubations were performed in multiwell plates with 14C-testosterone as substrate, in the...

Enhanced corticosterone release by female compared to male rats under basal and stress conditions has been frequently evidenced (1). The demonstration that gonadectomy enhances stress-induced corticosterone secretion in male rats (2) but reduces such levels in female rats (3) suggests a causal association between gonadal steroids and corticosterone release. The present study examined the corticosterone profile of intact and gonadectomised female and male rats under basal and s...

Most tests of the hypothalamo-pituitary-adrenal axis (HPA) use total cortisol measurements, although only free cortisol is biologically active. Total cortisol is 90% bound to cortisol binding globulin (CBG). CBG varies between individuals, is elevated by oestrogens and reduced by acute illness or surgery. Low CBG levels may result in individuals apparently failing such tests, and receiving inappropriate steroid replacement. We hypothesised that correcting total cortisol for CB...

THE REGULATION OF ADRENOMEDULLIN AND PROADRENOMEDULLIN N-TERMINAL 20 PEPTIDE IN THE ADRENAL GLAND: THE DIFFERENCE BETWEEN ADRENOCORTICAL CELLS AND CHROMAFFIN CELLS.Vakharia K, Hinson JP.Department of Endocrinology, Lab 1.2 Dominion House, Queen Mary University of London, London E, UK.It has been established that the adrenomedullin gene is expressed in the adrenal cortex and adrenal medulla, and that both adre...

Many laboratories offer a simple ratio of total testosterone (T):SHBG as an index (FAI) of free androgens. Methods for measuring free T (fT) are time consuming (equilibrium dialysis, ED) or reveal concentrations at odds with accepted values (RIA). The validity of FAI has been questioned and an alternative assessment by computation of fT recommended (1). We use a simpler calculation (2) producing results comparable to established literature. We have compared results obtained by...

Introduction. As for many minor metabolites of steroids, no authentic standard is commercially available for 18-OH-THA. This compound is the principal urinary metabolite of 18-hydroxycorticosterone, a putative intermediate in the synthesis of aldosterone and of diagnostic value in screening for hypermineralocorticoidism. Since de novo synthesis is time-consuming and expensive, we tested the possibility of using beta-cortol, which produces an ion at m/z 457 in common wit...

Annexin 1 (ANXA1) belongs to a well-conserved superfamily of structurally-related Ca2+ and phospholipid-binding proteins. We first described its induction and role as a mediator of glucocorticoid (GC) actions within the host defence and neuroendocrine systems. In addition we provided evidence that an extracellular pool of ANXA1 is responsible for many of the regulatory actions of the protein, particularly in the pituitary gland where ANXA1 exported from folliculoste...

The secondary sexual characteristics such as a neck mane and antlers seen in the male red deer are unusual in that they are produced on an annual basis and are linked to the breeding season. This cycle is highly controlled and the development of these characteristics coincides with changes in plasma levels of testosterone and IGF-1. We have previously shown that the expression of the androgen receptor in the hair follicle cells of the neck mane are only present during the bree...