Role of female gonadal hormones in the CNS: clinical and experimental aspects

The large body of evidence presented indicates that in the brain the action of sex hormones cannot be thought as restricted to the regulation of endocrine functions and mating behavior. Estrogens and progesterone seem to act in numerous regions of the CNS to regulate motor as well as limbic functions. Furthermore, the data reviewed indicate that these hormones may modulate neuronal activity through a wide variety of mechanisms. More studies should focus on such mechanisms in order to better understand the role of sex hormones in the CNS and to devise ways of limiting their effects on depression, epilepsy etc. It is known that in peripheral target organs these hormones modulate cell activities by binding to specific receptors which can recognize the DNA sequence and activate the transcription of selected genes (135, 136). There is evidence supporting the hypothesis that this mechanism of action has been conserved also in the brain. First, the brain receptors for progesterone and estrogens are functionally and biochemically indistinguishable from those in the periphery (4, 5): they may be concentrated in neuronal nuclei and bind chromatin "in vitro" (7). Second, a temporal relationship has been observed between administration of steroids and the increase of polymerase II activity (137) and protein synthesis (4, 5). Third, various hormone-induced behaviors may be blocked by inhibitors of the protein synthesis (138, 139, 140, 141). However, sex hormones must be capable to regulate neuronal functions by mechanisms other then genomic. In fact, the topical application of estrogen or progesterone on nervous tissue results in a rapid change of membrane potential (60, 71). Such a rapid effect is not likely to be the consequence of nuclear action, but rather must be related to events occurring on the cell surface. It has been hypothesized that sex steroids affect the fluidity of the cell membrane, therefore modifying the ion transport or neurotransmitter receptor activity (142). If this were the case we would expect to observe a similar effect after application of any steroid. Experimental evidence demonstrates that not all the steroids affect the nervous membrane potential. Moreover, two steroids, estradiol and progesterone, have been described to modulate membrane potential in an opposite way (66, 67, 69, 75). At the moment, there is no evidence for the presence of steroid receptors on neuronal membranes which could mediate the described phenomena.(ABSTRACT TRUNCATED AT 400 WORDS)

[Value of the assay of urinary gonadotropins in pediatric endocrinology]

An assay for urinary gonadotropins (UG) performed after acetone extraction is presented. This dosage was performed either on a sample of the 24 assay urine, or on the fractionated 12 hr/12 hr urines (night/day) in normal children whose ages ranged from 2 to 20 years and in children presenting with various endocrine diseases (on about 2,000 urine samples). Normal values were established according to sex and stage of puberty. In boys, the lack of overlap between values of LH (UI/24 hr) observed in stage I (prepubescent, 9-13 yrs) and those observed in stage II represents an obvious biological marker of the onset of puberty. The night/day ratio of LH also increases close to puberty, reflecting the onset of the well-known night secretion of LH, at the time of the first stages of puberty. In girls, the preferential increase in FSH is the best criterion for the onset of puberty. In children with endocrine diseases, assay for UG/24 hr is a valuable parameter of the gonadotropic function allowing 1. to separate delayed puberty from hypogonadotropic hypogonadism; 2. to confirm a diagnosis of precocious puberty and 3. to control a treatment with LHRH analogous.

Leukotriene C4 binds to human glomerular epithelial cells and promotes their proliferation in vitro

In human and experimental glomerulonephritis, glomerular hypercellularity results both from accumulation of macrophages and proliferation of resident glomerular cells. The recent identification of macrophage-derived factors that stimulate mesangial and epithelial cell proliferation suggests that these factors might contribute to the hypercellularity. To determine the identity of such macrophage-derived growth factors, we studied the effect of leukotrienes (LTs), products that are released from macrophages and leukocytes, on proliferation of human glomerular epithelial cells in culture. Dose-dependent (1-100 nM) stimulation of [3H]thymidine incorporation, an index of cell proliferation, was observed in cells incubated with the sulfidopeptide LTs, LTC4 and LTD4, but not with LTB4. The response was 248 and 172% of control values at 100 nM LTC4 and LTD4, respectively. This effect of LTC4 was abolished by FPL 55712. Subsequent binding studies demonstrated that glomerular epithelial cells possess specific receptors for LTC4. [3H]LTC4 bound rapidly at 8 degrees C to the cells. There was a plateau after 40 min incubation. Maximum specific binding was 70-90% of total binding. Specific binding was totally reversible with addition of an excess of unlabeled LTC4. Analysis of time-course association slopes at two concentrations of [3H]LTC4 and of the competition between a single concentration of [3H]LTC4 and increasing concentrations of unlabelled LTC4 allowed calculation of dissociation constants (Kd) of 220 and 217 nM, respectively. Both LTD4 and LTE4 exhibited ED50 values that were at least one order of magnitude higher than for LTC4. Thus, our findings suggest that LTC4 binds to specific receptors of glomerular epithelial cells, promotes proliferation of these cells, and could contribute to epithelial hypercellularity found in glomerulonephritis.

Fibrinopeptide A: a marker of acute coronary thrombosis

To determine whether coronary thrombosis in vivo is reflected by elevations in levels of fibrinopeptide A (FPA) in plasma, we sequentially characterized plasma FPA levels associated with evolving infarction in patients admitted to the cardiac care unit early after the onset of symptoms, in patients with transmural infarction admitted later, and in patients with nontransmural infarction. Studies were also performed in patients in whom the diagnosis of infarction was suspected but subsequently excluded. FPA values were significantly higher in patients with transmural infarction (42.3 +/- 11.2 ng/ml [mean +/- SEM], n = 53) compared with those in patients with nontransmural infarction (4.8 +/- 1.6 ng/ml, n = 17) or with those in patients in whom infarction was subsequently excluded as a diagnosis (3.5 +/- 0.6 ng/ml, n = 17, p less than .01 for both). Elevations in FPA level were greatest in patients with transmural infarction from whom samples were obtained soon after the onset of symptoms. Thus, in 39 patients from samples were obtained within 10 hr after the onset of symptoms, FPA levels were significantly higher than in 14 patients from whom samples were obtained initially more than 10 hr after the onset of symptoms (55.5 +/- 14.7 vs 4.9 +/- 1.4 ng/ml, p less than .01). In 30 of the 39 patients with evolving transmural infarction from whom samples were obtained within the first 10 hr after the onset of symptoms, the level of FPA was greater than 8 ng/ml.(ABSTRACT TRUNCATED AT 250 WORDS)

Experimental and Theoretical-Study of Carbon-Fluorine Couplings in the NMR-Spectra of 2-Fluoroaryl Ketones

Calculations by the IPPP-INDO method give the spin-spin coupling constants for the side-chain carbons, 3JCF and 4JCF, as 4.97 and 6.86 Hz respectively with substantial contributions to through-space coupling from the pathway CO-C-H…F. The observed values for 1-(2- fluorophenyl ) ethanone , 3.3 and 7.2 Hz, and for 1-(2,5- difluorophenyl ) ethanone , 3.7 and 7.3 Hz, are in good agreement with these predictions. Two compounds, a dihydroindenone and a naphthalenone, in which this pathway cannot be effective, show no fluorine coupling to the aliphatic carbon next to the carbonyl and the values of 3JCF are reduced to 2.2 and 2.5 Hz, consistent with the loss of a through-space Fermi contact term of the kind described above.

Differential stimulation of PGE2 synthesis in mesangial cells by angiotensin and A23187

The mechanism of arachidonic acid release and prostaglandin E2 (PGE2) synthesis was studied in cultured mesangial cells from rat kidneys. Both the ionophore A23187 and angiotensin II stimulated radioimmunoassayable PGE2 synthesis. The effect of angiotensin occurred within minutes, with half-maximal stimulation around 10(-9) M. In cells prelabeled with [14C]arachidonate, A23187 caused release of [14C]-arachidonate from all phospholipids. In contrast, angiotensin II caused preferential release of [14C]arachidonate from phosphatidylinositol, associated with a significant increase in 14C-labeled phosphatidic acid, mono- and diacylglyceride, and arachidonate. These results indicate that angiotensin preferentially, but not exclusively, stimulates a phosphatidylinositol-specific phospholipase C, whereas A23187 results in unspecific stimulation of phospholipases. The tight coupling between an angiotensin-responsive phospholipid-arachidonate pool and cyclooxygenase may be responsible for the specificity of the response to angiotensin.

Variability of airway responsiveness to histamine aerosol in normal subjects. Role of deposition

The purpose of this investigation was to determine if the variability of bronchial responsiveness to inhaled histamine in normal subjects is related to the total dose of histamine deposited in the airways. To test this possibility, we used a new method of histamine challenge that permits calculating the histamine mass deposited in the airways in an attempt to correlate it with the magnitude of the response. Using a standardized breath-holding maneuver, 10 healthy nonsmokers and 10 healthy smokers with normal spirometry inhaled an aerosol generated from a solution containing a fixed ratio of histamine and a small quantity of hematoporphyrin serving as a fluorescent tracer. The mass of histamine deposited was calculated from the measured fluorescence of the inspired and expired aerosol. Forced expiratory volume in one second (FEV1) was measured before and 10 min after inhalation challenge. There was a negative correlation between percent decrease in FEV1 (delta FEV1) and histamine mass deposited in the nonsmokers (r = -0.83, p less than 0.005) and smokers (r = -0.82, p less than 0.005) without a difference between the 2 slopes. The range of delta FEV1 was 7 to 33% and of histamine mass deposited, 0.02 to 0.18 mg in the nonsmokers. The respective values in the smokers were 2 to 30% and 0.02 to 0.17 mg. In 6 subjects in whom dose-response curves were obtained, the mean deposited histamine mass required to decrease the FEV1 by 10% was 0.11 mg.(ABSTRACT TRUNCATED AT 250 WORDS)

Progesterone and estrogens in rat brain: modulation of GABA (gamma-aminobutyric acid) receptor activity

Our data indicate that estrogens and progesterone can regulate the number of GABA receptors (as detected by [3H]muscimol binding assay) in rat brain. Both hormones act in selected areas. The extent of the effect (up to 160% increase) and the number of areas responsive suggest that sex hormones may play a very important role in the regulation of the functions of GABAergic transmission in the central nervous system.

Effect of platelet-activating factor and serum-treated zymosan on prostaglandin E2 synthesis, arachidonic acid release, and contraction of cultured rat mesangial cells

The interaction of inflammatory cells and glomerular prostaglandins (PG) may be important during glomerulonephritis. We therefore examined the influence of platelet-activating factor (PAF), (a mediator of inflammation released from leukocytes) and of phagocytosis of zymosan on arachidonic acid metabolism and on cell contractility in rat glomerular mesangial cells in culture. PAF increased PGE2 synthesis (determined by radioimmunoassay) within minutes (threshold: 10(-10)M; maximal effect: 10(-7)M). Serum-treated zymosan also stimulated PGE2, but with a slower onset. In cells prelabeled with [14C]arachidonic acid both PAF and serum-treated zymosan released 14C from phospholipids and increased free [14C]arachidonate. The ratio of 14C-release to PGE2 was, however, different with PAF and serum-treated zymosan, indicating different phospholipid pools. Under phase-contrast microscopy, PAF caused contraction of mesangial cells with a dose-response and time-course parallel to that for PGE2 synthesis. Serum-treated zymosan caused no contraction. The PAF-induced contraction was enhanced by PG synthesis inhibition and was attenuated by addition of PGE2, indicating a feedback mechanism. The mesangial contraction by PAF may be important in favoring deposition of immune complexes, while the PGE2 synthesis stimulated by PAF and by phagocytosis of zymosan may counteract the deleterious effects of PAF during induction of glomerulonephritis.

Reactive oxygen production by cultured rat glomerular mesangial cells during phagocytosis is associated with stimulation of lipoxygenase activity

To investigate the phagocytic capability of glomerular mesangial cells and the biochemical events associated with phagocytosis, rat cultured mesangial cells were incubated in the presence of opsonized zymosan (STZ) and production of reactive-oxygen species and lipoxygenase products were determined. Mesangial cells were identified on the basis of morphologic (presence of microfilaments and pattern of staining by an anti-myosin antiserum) and physiologic (contractile activity in response to angiotensin II) characteristics. No contamination by esterase-positive cells was observed. Electron microscopy revealed that the phagocytic process started after 5 min of incubation, and affected approximately 50% of the cells. Superoxide anion (.O2-) and hydrogen peroxide (H2O2) generation by mesangial cells exposed to STZ increased with time and STZ concentration. Cells incubated with zymosan particles treated with heated serum produced undetectable amounts of .O2- and 6 times less H2O2 than cells exposed to STZ. Pretreatment by cytochalasin B produced a marked decrease in STZ-stimulated production of reactive oxygen species. [3H]Arachidonic acid was incorporated into mesangial cell phospholipids and its release and conversion into monohydroxyeicosatetraenoic acids (HETE) was measured by radiometric high performance liquid chromatography (HPLC). Incubation with STZ markedly stimulated the release of arachidonic acid from its phospholipid stores and its transformation into 11-, 12-, and 15-HETE. Lipoxygenase inhibitors inhibited STZ-stimulated H2O2 production, whereas they did not modify the phagocytic process as shown by the absence of any effect on the uptake of 125I-STZ by the mesangial cells. This study demonstrates that a high percentage of rat cultured mesangial cells phagocytose opsonized particles. The phagocytic process results in an oxidative burst that appears to be dependent on stimulation of the lipoxygenase pathway.

[Effect of cycloheximide on glucan biosynthesis in the growth process of Saccharomyces carlsbergensis yeasts]

Biosynthesis of alkali-acid-insoluble beta-glucan was studied in the course of growth of the yeast Saccharomyces carlsbergensis IBPM Y366. Synthesis of this important component of the cell wall was shown to depend on the stage of the cultural growth. The rate of 14C-glucose incorporation into the glucan fraction was maximal at the beginning and in the middle of the logarithmic growth phase. Cycloheximide, an inhibitor of protein synthesis, at a concentration of 10 micrograms/ml inhibited glucan synthesis at the beginning and by the end of the logarithmic growth phase, but stimulated synthesis of this polymer in the middle of the logarithmic phase of growth of this organism.

Kinetic disposition and diuretic effect of frusemide in acute pulmonary oedema

The kinetic disposition and diuretic effect of frusemide was assessed in 16 patients with acute pulmonary oedema utilizing a specific gas-liquid chromatographic assay for the drug. Serum frusemide concentrations decayed biexponentially with wide variation in both alpha half-life (range 15-79 min) and beta half-life (range 127-1190 min). The beta phase half-life was inversely related to creatine clearance. The apparent volume of distribution varied greatly among the patients (range 0.085-0.818 l/kg), and patients with an acute myocardial infarction had a larger peripheral kinetic compartment. Patients with acute myocardial infarction excreted less unchanged drug and had a lesser urinary excretion of sodium and volume compared to patients without infarction. The urinary excretion of sodium, chloride, calcium and volume was linearly related to the urinary excretion of unchanged frusemide.

Biotransformation of furosemide in patients with acute pulmonary edema

Furosemide (20-80 mg) was administered iv over 5 min to 16 patients with the diagnosis of acute pulmonary edema due to left heart failure. Serum and urine samples collected during the 24 hr after administration were assayed for furosemide and its biotransformation products by gas-liquid chromatography. A biexponential decay of serum furosemide concentrations vs. time was observed. Recovery of furosemide and its metabolites from urine in 24 hr varied between 30 and 98% of the administered dose. The excretion of unchanged drug accounted for 22.6-73.4% of the dose. The excretion of the glucuronide metabolite and 2-amino-4-chloro-5-sulfamoylanthranilic acid accounted for 3.3-40.4% and from 0.13-3.92% of the dose, respectively. Urinary excretion of furosemide was less in patients with, than in those without, myocardial infarction. Urinary excretion of the oxidative acidic metabolite was increased in patients with reduced creatinine clearance. The glucuronide metabolite of furosemide was the major biotransformation product in these patients with acute pulmonary edema.

Pharmacokinetic disposition and protein binding of furosemide in newborn infants

Using a one-compartment model, the pharmacokinetic disposition of furosemide was studied in eight premature and term neonates with fluid overload. Following a single intravenous injection of furosemide (1 to 1.5 mg/kg), multiple blood samples were obtained from a heelstick or an arterial catheter and analyzed for furosemide by gas liquid chromatography. The mean (+/- SE) apparent volume of distribution was 829.2 +/- 118.9 ml/kg; t1/2 was 7.7 +/- 1.0 hour; elimination rate constant was 0.102 +/- 0.013/hour and plasma clearance was 81.61 +/- 14.98 ml/kg/hour. Compared to the disposition of furosemide in normal adults. AVd is almost fourfold greater in the neonate with an eightfold prolongation in plasma t1/2, an eightfold decrease in Ke1, and a twofold decrease in plasma clearance. Neither gestational and postnatal age nor birth weight correlated with the pharmacokinetic variables. No significant change in reserve bilirubin-binding capacity after an intravenous dose of furosemide was noted. Slow elimination of furosemide may partly explain the prolonged diuretic and saluretic effect of furosemide in the neonate.

Treatment of accidental hypothermia with peritoneal dialysis

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Peritoneal localization of gallium-67

Diffuse abdominal localization of 67Ga was found in two patients with peritonitis; one due to M. tuberculosis, and the other presumably pyogenic, following multiple perforations of the small bowel due to necrotizing ulcerating enteritis. After 7 months of antituberculous treatment of the first patient, a normal gallium distribution was noted. It is suggested that gallium scanning may be useful in the diagnosis of peritonitis and perhaps of other serosal infections.

Hemorrhoidectomy--how I do it: experience with the St. Mark's Hospital technique for emergency hemorrhoidectomy

Eighty-five patients who had thrombosed hemorrhoids underwent emergency hemorrhoidectomy according to St. Mark's Hospital technique, with very good results. All specimens were found to have dilated blood vessels filled with thrombi of different sizes, with irregular, fibrotic or hyalinized vascular walls. Early complications included urinary retention and painful defecation in some patients. Late complications included only skin tags. No sepsis was found among our patients. Although operative bleeding can be tedious during the hemorrhoidectomy, it was a complication in the postoperative period of only one patient. Segmental, open hemorrhoidectomy performed according to the St. Mark's Hospital technique has been shown to be an ideal operation for the treatment of patients who have hemorrhoidal thrombosis, prolapse, edema, and bleeding.

Successful correction of all mechanical complications of ischemic heart disease in the same patient

Extensive surgery for all of the mechanical complications of ischemic heart disease is feasible with early diagnosis, catheterization, and aggressive medical and surgical therapy. A patient is report who, after recovering from cardiogenic shock, required a coronary bypass, closure of ventricular septal defects, mitral valve replacement, aneurysmectomy, and temporary pacemaker wires. The outcome was successful.