Enzymatic sulfation of steroids. XIX. Cortisol sulfotransferase activity, glucocorticoid sulfotransferases, and tyrosine aminotransferase induction in chicken, gerbil, and and hamster liver

1985 ◽  
Vol 63 (1) ◽  
pp. 23-32 ◽  
Author(s):  
Sanford S. Singer ◽  
Edward G. Galaska ◽  
Theresa A. Feeser ◽  
Robert L. Benak ◽  
Anne Z. Ansel ◽  
...  

Radioisotopic, pH 6.8 assays were designed to measure hepatic cortisol sulfation in chickens, gerbils, and hamsters of both sexes. Enzyme levels with 40 μM cortisol were similar in males of all three species and due mostly to low Km enzymes with 10–30 μM cortisol Km's. Maximum enzyme activity in male chickens required 40 μM Cortisol. In the other species, the much higher maximum enzyme activity observed required 500 μM cortisol owing to sulfotransferases with Km's for the hormone near 300 μM. Coenzyme 3′-phosphoadenosine-5′-phosphosulfate requirements also varied between species. Sex differences of the enzyme levels were found only in hamsters. There, males possessed only 24–33% of the enzyme levels found in females. Cortisol 21-sulfate was the reaction product in all of the species. Sexual dimorphism in hamsters appeared to be due to repressive effects of androgens. pH optima of enzyme activities in the three species ranged from pH 6 to 7. Routine use of pH 6.8 assays allowed representative interspecies comparisons. DEAE-Sephadex fractionation of cytosol showed that chicken liver contained mostly two enzymes with different pH optima that catalyzed cortisol sulfation. These differed from the enzymes that catalyzed dehydroepiandrosterone and estradiol sulfation. In the gerbil four enzymes with similar pH optima catalyzed cortisol sulfation. The second of these to elute from DEAE-Sephadex columns was the low Km form. In hamsters most glucocorticoid sulfotransferase activity appeared to be due to one enzyme. The molecular weights of the low Km gerbil enzyme and the main hamster enzyme were 98 300 ± 6100 and 105 000 ± 8100. Hamsters and gerbils responded to injection of cortisol by hepatic tyrosine aminotransferase induction.

1972 ◽  
Vol 129 (3) ◽  
pp. 645-655 ◽  
Author(s):  
J. S. Heller ◽  
C. L. Villemez

A neutral-detergent-solubilized-enzyme preparation derived from Phaseolus aureus hypocotyls contains two types of glycosyltransferase activity. One, mannosyltransferase enzyme activity, utilizes GDP-α-d-mannose as the sugar nucleotide substrate. The other, glucosyltransferase enzyme activity, utilizes GDP-α-d-glucose as the sugar nucleotide substrate. The soluble enzyme preparation catalyses the formation of what appears to be a homopolysaccharide when either sugar nucleotide is the only substrate present. A β-(1→4)-linked mannan is the only polymeric product when only GDP-α-d-mannose is added. A β-(1→4)-linked glucan is the only polymeric product when only GDP-α-d-glucose is added. In the presence of both sugar nucleotides, however, a β-(1→4)-linked glucomannan is formed. There are indications that endogenous sugar donors may be present in the enzyme preparation. There appear to be only two glycosyltransferases in the enzyme preparation, each catalysing the transfer of a different sugar to the same type of acceptor molecule. The glucosyltransferase requires the continual production of mannose-containing acceptor molecules for maintenance of enzyme activity, and is thereby dependent upon the activity of the mannosyltransferase. The mannosyltransferase, on the other hand, does not require the continual production of glucose-containing acceptors for maintenance of enzyme activity, but is severely inhibited by GDP-α-P-glucose. These properties promote the synthesis of β-(1→4)-linked glucomannan rather than β-(1→4)-linked glucan plus β-(1→4)-linked mannan when both sugar nucleotide substrates are present.


1967 ◽  
Vol 39 (4) ◽  
pp. 555-564 ◽  
Author(s):  
HEIDI H. SWANSON

SUMMARY Unlike rats, the adult female hamster is heavier and longer than the male. The small size of the males appears to be dependent on the continuous presence of androgens, since castration before or after puberty results in an immediate acceleration of ponderal and linear growth, which is maintained until the female size is reached. The growth of females is not affected by gonadectomy. Another sexual dimorphism which is reversed in hamsters in comparison with rats is adrenal weight; males have heavier adrenals than females. Castration reduces both absolute and relative adrenal weights of males to the levels of females. It is possible that the sex difference in growth is mediated through a differential secretion of adrenal hormones. On the other hand, the sexual dimorphism in pituitary weights of hamsters is similar to rats; females have heavier pituitaries than males. This may reflect a sex difference in the pattern of gonadotrophin secretion, which may be similar in both species.


Author(s):  
I. R. Khuzina ◽  
V. N. Komarov

The paper considers a point of view, based on the conception of the broad understanding of taxons. According to this point of view, rhyncholites of the subgenus Dentatobeccus and Microbeccus are accepted to be synonymous with the genus Rhynchoteuthis, and subgenus Romanovichella is considered to be synonymous with the genus Palaeoteuthis. The criteria, exercising influence on the different approaches to the classification of rhyncholites, have been analyzed (such as age and individual variability, sexual dimorphism, pathological and teratological features, degree of disintegration of material), underestimation of which can lead to inaccuracy. Divestment of the subgenuses Dentatobeccus, Microbeccus and Romanovichella, possessing very bright morphological characteristics, to have an independent status and denomination to their synonyms, has been noted to be unjustified. An artificial system (any suggested variant) with all its minuses is a single probable system for rhyncholites. The main criteria, minimizing its negative sides and proving the separation of the new taxon, is an available mass-scale material. The narrow understanding of the genus, used in sensible limits, has been underlined to simplify the problem of the passing the view about the genus to the other investigators and recognition of rhyncholites for the practical tasks.


2021 ◽  
Vol 22 (9) ◽  
pp. 4620
Author(s):  
Holly J. Woodward ◽  
Dongxing Zhu ◽  
Patrick W. F. Hadoke ◽  
Victoria E. MacRae

Sex differences in cardiovascular disease (CVD), including aortic stenosis, atherosclerosis and cardiovascular calcification, are well documented. High levels of testosterone, the primary male sex hormone, are associated with increased risk of cardiovascular calcification, whilst estrogen, the primary female sex hormone, is considered cardioprotective. Current understanding of sexual dimorphism in cardiovascular calcification is still very limited. This review assesses the evidence that the actions of sex hormones influence the development of cardiovascular calcification. We address the current question of whether sex hormones could play a role in the sexual dimorphism seen in cardiovascular calcification, by discussing potential mechanisms of actions of sex hormones and evidence in pre-clinical research. More advanced investigations and understanding of sex hormones in calcification could provide a better translational outcome for those suffering with cardiovascular calcification.


2021 ◽  
Vol 22 (15) ◽  
pp. 8111
Author(s):  
Kuang-Hsu Lien ◽  
Chao-Hui Yang

The triad of noise-generated, drug-induced, and age-related hearing loss is the major cause of acquired sensorineural hearing loss (ASNHL) in modern society. Although these three forms of hearing loss display similar underlying mechanisms, detailed studies have revealed the presence of sex differences in the auditory system both in human and animal models of ASNHL. However, the sexual dimorphism of hearing varies among noise-induced hearing loss (NIHL), ototoxicity, and age-related hearing loss (ARHL). Importantly, estrogen may play an essential role in modulating the pathophysiological mechanisms in the cochlea and several reports have shown that the effects of hormone replacement therapy on hearing loss are complex. This review will summarize the clinical features of sex differences in ASNHL, compare the animal investigations of cochlear sexual dimorphism in response to the three insults, and address how estrogen affects the auditory organ at molecular levels.


BMC Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Basabi Bagchi ◽  
Quentin Corbel ◽  
Imroze Khan ◽  
Ellen Payne ◽  
Devshuvam Banerji ◽  
...  

Abstract Background Sexual dimorphism in immunity is believed to reflect sex differences in reproductive strategies and trade-offs between competing life history demands. Sexual selection can have major effects on mating rates and sex-specific costs of mating and may thereby influence sex differences in immunity as well as associated host–pathogen dynamics. Yet, experimental evidence linking the mating system to evolved sexual dimorphism in immunity are scarce and the direct effects of mating rate on immunity are not well established. Here, we use transcriptomic analyses, experimental evolution and phylogenetic comparative methods to study the association between the mating system and sexual dimorphism in immunity in seed beetles, where mating causes internal injuries in females. Results We demonstrate that female phenoloxidase (PO) activity, involved in wound healing and defence against parasitic infections, is elevated relative to males. This difference is accompanied by concomitant sex differences in the expression of genes in the prophenoloxidase activating cascade. We document substantial phenotypic plasticity in female PO activity in response to mating and show that experimental evolution under enforced monogamy (resulting in low remating rates and reduced sexual conflict relative to natural polygamy) rapidly decreases female (but not male) PO activity. Moreover, monogamous females had evolved increased tolerance to bacterial infection unrelated to mating, implying that female responses to costly mating may trade off with other aspects of immune defence, an hypothesis which broadly accords with the documented sex differences in gene expression. Finally, female (but not male) PO activity shows correlated evolution with the perceived harmfulness of male genitalia across 12 species of seed beetles, suggesting that sexual conflict has a significant influence on sexual dimorphisms in immunity in this group of insects. Conclusions Our study provides insights into the links between sexual conflict and sexual dimorphism in immunity and suggests that selection pressures moulded by mating interactions can lead to a sex-specific mosaic of immune responses with important implications for host–pathogen dynamics in sexually reproducing organisms.


1987 ◽  
Vol 60 (3) ◽  
pp. 875-883
Author(s):  
Nancy Lipsitt ◽  
Rose R. Olver

The relative contribution of sex and situation has become a contested issue in the understanding of sex differences in behavior. In the present study, 20 male and 20 female undergraduates were asked to describe their behavior and thoughts in six everyday college situations. Three of the situations were constructed to be typically male and three typically female in content. The results indicate that men and women demonstrate sex-specific characteristics in their responses regardless of the type of situation presented. Men exhibited concern with separateness from others, while women exhibited concern with sustaining connection to others, even when faced with situations described to present demand properties that might be expected specifically to elicit the concern characteristic of the other sex. However, for these students the situation also made a difference: female-defined situations elicited the most masculine responses for both male and female subjects.


2012 ◽  
Vol 60 (2) ◽  
pp. 101 ◽  
Author(s):  
Thomas E. White ◽  
Joseph Macedonia ◽  
Debra Birch ◽  
Judith Dawes ◽  
Darrell J. Kemp

Structurally generated colours are at least as commonplace and varied components of animal signals as pigment colours, yet we know far less about the former, both in terms of the patterns and phenotypic variation and of their underlying correlates and causes. Many butterflies exhibit bright and iridescent colour signals that arise from a characteristic ‘ridge-lamellar’ scale surface nanoarchitecture. Although there are multiple axes of functional variation in these traits, few have been investigated. Here we present evidence that sexual dimorphism in the expression of a sexually homologous ridge-lamellar trait (iridescent ultraviolet) is mediated by sex differences in the density of lamellar-bearing scale ridges. This trait – ridge density – has also been causally related to iridescent signal variation in other coliadines (e.g. C. eurytheme), which suggests that it may offer a common basis to both intra- and intersexual differences in ultraviolet wing reflectance among these butterflies.


1939 ◽  
Vol 69 (6) ◽  
pp. 819-831 ◽  
Author(s):  
Jaques Bourdillon

In serum of patients with nephrosis both albumin and globulin showed by osmotic pressure nearly double the molecular weights of normal albumin and globulin. In the urines of such patients, on the other hand, both proteins showed molecular weights lower even than in normal serum. The colloidal osmotic pressures were measured by the author's method at such dilutions that the van't Hoff law relating pressures to molecular concentrations could be directly applied. For the albumin and globulin of normal serum the molecular weights found were 72,000 and 164,000 respectively, in agreement with the weights obtained by other methods.


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