scholarly journals Endocrine regulation of sex differences in hepatic histidase activity

1985 ◽  
Vol 231 (3) ◽  
pp. 785-787 ◽  
Author(s):  
C A Lamartiniere

Hepatic histidase activity in adult female rats is twice that in adult male rats. Hypophysectomy and thyroidectomy result in a significant increase in hepatic histidase activities in males, but not in females. This effect on histidase is reversed by the exogenous administration of tri-iodothyronine, but not by ectopic pituitary glands or purified pituitary hormones.

1977 ◽  
Vol 73 (1) ◽  
pp. 67-70 ◽  
Author(s):  
SAM SHUSTER ◽  
WENDY M. HINKS ◽  
A. J. THODY

SUMMARY The effect of progesterone on the rate of sebum secretion was examined in intact and gonadectomized rats. In intact, adult, male rats, progesterone administered for 3 weeks decreased sebum secretion; after castration of adult males, progesterone increased sebum secretion and an even greater response occurred in males castrated at 21 days of age. In intact, adult, female rats progesterone slightly increased sebum production. As in the male, the response was affected by the time of gonadectomy, a greater response occurring after spaying at 21 days compared with 10 weeks of age. Thus, the response to progesterone in the adult rat differs in intact males and females and is affected by changes in the endocrine environment induced by gonadectomy, especially near the time of puberty.


1963 ◽  
Vol 26 (3) ◽  
pp. 425-436 ◽  
Author(s):  
P. S. BROWN

SUMMARY A dithiocarbamoylhydrazine (ICI 33828) was injected s.c. into intact rats and mice. It usually caused a reduction in weight of the uterus or of the accessory organs in the male, but less commonly of the gonads. As little as 0·5 mg. daily for 4 days caused significant effects in adult female rats, while half this dose on alternate days retarded maturation in male rats. ICI 33828 was injected with exogenous gonadotrophin in three systems of assay and in some cases it modified the response to the gonadotrophin. This may not be due to a specific effect at the gonadal level but either to suppression of endogenous gonadotrophins in the test animals or to the effect of ICI 33828 on their general condition. Pituitary glands from male rats treated with ICI 33828 were assayed for follicle stimulating hormone (FSH) and found to contain significantly less than glands from control rats. This suggests that ICI 33828 acts by reducing the formation of pituitary gonadotrophin.


Author(s):  
Serah F. Ige ◽  
Waliyat O. Aremu ◽  
Bolade S. Olateju ◽  
Victor A. Oladipupo ◽  
Adedayo T. Adekola

Aims: Ulcerative colitis is a disease of the bowel that occurs in all ages and affects both males and females. This research study was designed to investigate the effect of age and sex on the healing of colitis in rats. Methodology: Twenty - eight rats were randomly distributed into four groups of seven animals per group; adult male rats, mid age male rats, adult female rats and mid age female rats. Mid age and adult Wistar rats were 7- 8weeks and 14 weeks old respectively. Colitis was induced through a single intra-colonic instillation of 7% acetic acid (1mL/100g body weight) and allowed to heal for 14 days. Blood samples were obtained for analysis. Colon samples were also obtained for histomorphological study and biochemical assays (Myeloperoxidase activities, Superoxide dismutase, Glutathione, Catalase and Malondialdehyde) levels. Results: There was no significant difference in Malondialdehyde concentration, catalase, Superoxide dismutase, Myeloperoxidase, Platelet Distribution Width, Platelet Count, Basophil cell numbers, Eosinophil cell numbers, platelet cells, Mean Platelet Volume , Mean Cell Volume and white blood cells across the groups. The Glutathione concentration in mid age male rats was significantly increased when compared with adult male rats. The haemoglobin , Lymphocytes and Mean Cell Haemoglobin levels were increased while neutrophils and monocyte levels were decreased in the younger female rats. The histomorphological study revealed poorly preserved surface epithelia layer of the colon in adult male rats while mid age male and female rats showed moderately preserved surface epithelia layer, adult female rats showed normal surface epithelia layer. Conclusion: Mid age rats heal faster than adult rats while in terms of sex, female rats tends to heal faster than male rats.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Ming Song ◽  
Fang Yuan ◽  
Xiaohong Li ◽  
Xipeng Ma ◽  
Xinmin Yin ◽  
...  

Abstract Background Inadequate copper intake and increased fructose consumption represent two important nutritional problems in the USA. Dietary copper-fructose interactions alter gut microbial activity and contribute to the development of nonalcoholic fatty liver disease (NAFLD). The aim of this study is to determine whether dietary copper-fructose interactions alter gut microbial activity in a sex-differential manner and whether sex differences in gut microbial activity are associated with sex differences in hepatic steatosis. Methods Male and female weanling Sprague-Dawley (SD) rats were fed ad libitum with an AIN-93G purified rodent diet with defined copper content for 8 weeks. The copper content is 6 mg/kg and 1.5 mg/kg in adequate copper diet (CuA) and marginal copper diet (CuM), respectively. Animals had free access to either deionized water or deionized water containing 10% fructose (F) (w/v) as the only drink during the experiment. Body weight, calorie intake, plasma alanine aminotransferase, aspartate aminotransferase, and liver histology as well as liver triglyceride were evaluated. Fecal microbial contents were analyzed by 16S ribosomal RNA (16S rRNA) sequencing. Fecal and cecal short-chain fatty acids (SCFAs) were determined by gas chromatography-mass spectrometry (GC-MS). Results Male and female rats exhibit similar trends of changes in the body weight gain and calorie intake in response to dietary copper and fructose, with a generally higher level in male rats. Several female rats in the CuAF group developed mild steatosis, while no obvious steatosis was observed in male rats fed with CuAF or CuMF diets. Fecal 16S rRNA sequencing analysis revealed distinct alterations of the gut microbiome in male and female rats. Linear discriminant analysis (LDA) effect size (LEfSe) identified sex-specific abundant taxa in different groups. Further, total SCFAs, as well as, butyrate were decreased in a more pronounced manner in female CuMF rats than in male rats. Of note, the decreased SCFAs are concomitant with the reduced SCFA producers, but not correlated to hepatic steatosis. Conclusions Our data demonstrated sex differences in the alterations of gut microbial abundance, activities, and hepatic steatosis in response to dietary copper-fructose interaction in rats. The correlation between sex differences in metabolic phenotypes and alterations of gut microbial activities remains elusive.


Author(s):  
Olga Wronikowska ◽  
Maria Zykubek ◽  
Łukasz Kurach ◽  
Agnieszka Michalak ◽  
Anna Boguszewska-Czubara ◽  
...  

Abstract Rationale Mephedrone is a frequently overused drug of abuse that belongs to the group of novel psychoactive substances. Although its mechanism of action, as well as toxic and psychoactive effects, has been widely studied, the role of different factors that could contribute to the increased vulnerability to mephedrone abuse is still poorly understood. Objectives The aim of the presented study was to assess the impact of several factors (sex differences, social-conditioning, and chronic mild unpredictable stress — CMUS) on the liability to mephedrone-induced reward in Wistar rats. Methods The rewarding effects of mephedrone in male and female rats were assessed using the conditioned place preference (CPP) procedure. Furthermore, the impact of social factor and stress was evaluated in male rats using social-CPP and CMUS-dependent CPP, respectively. Results Mephedrone induced classic-CPP in female (10 mg/kg), as well as in male (10 and 20 mg/kg) rats. However, the impact of mephedrone treatment during social-CPP was highly dose-dependent as the rewarding effects of low dose of mephedrone (5 mg/kg; non-active in classic-CPP) were potentiated when administered during social-conditioning. Interestingly, social-conditioning with a higher dose of 20 mg/kg (that induced classic-CPP) was able to reverse these effects. Finally, CMUS potentiated rewarding effects of a low dose of mephedrone (5 mg/kg) and increased the level of corticosterone in rats’ prefrontal cortex and hippocampus. Conclusions Altogether, the presented results give new insight into possible factors underlying the vulnerability to mephedrone abuse and can serve as a basis for further studies assessing mechanisms underlying observed effects.


2019 ◽  
Vol 22 (11) ◽  
pp. 710-723 ◽  
Author(s):  
Atul P Daiwile ◽  
Subramaniam Jayanthi ◽  
Bruce Ladenheim ◽  
Michael T McCoy ◽  
Christie Brannock ◽  
...  

Abstract Background Methamphetamine (METH) use disorder is prevalent worldwide. There are reports of sex differences in quantities of drug used and relapses to drug use among individuals with METH use disorder. However, the molecular neurobiology of these potential sex differences remains unknown. Methods We trained rats to self-administer METH (0. 1 mg/kg/infusion, i.v.) on an fixed-ratio-1 schedule for 20 days using two 3-hour daily METH sessions separated by 30-minute breaks. At the end of self-administration training, rats underwent tests of cue-induced METH seeking on withdrawal days 3 and 30. Twenty-four hours later, nucleus accumbens was dissected and then used to measure neuropeptide mRNA levels. Results Behavioral results show that male rats increased the number of METH infusions earlier during self-administration training and took more METH than females. Both male and female rats could be further divided into 2 phenotypes labeled high and low takers based on the degree of escalation that they exhibited during the course of the METH self-administration experiment. Both males and females exhibited incubation of METH seeking after 30 days of forced withdrawal. Females had higher basal mRNA levels of dynorphin and hypocretin/orexin receptors than males, whereas males expressed higher vasopressin mRNA levels than females under saline and METH conditions. Unexpectedly, only males showed increased expression of nucleus accumbens dynorphin after METH self-administration. Moreover, there were significant correlations between nucleus accumbens Hcrtr1, Hcrtr2, Crhr2, and Avpr1b mRNA levels and cue-induced METH seeking only in female rats. Conclusion Our results identify some behavioral and molecular differences between male and female rats that had self-administered METH. Sexual dimorphism in responses to METH exposure should be considered when developing potential therapeutic agents against METH use disorder.


1986 ◽  
Vol 108 (3) ◽  
pp. 399-403 ◽  
Author(s):  
R. L. Pérez ◽  
G. A. Machiavelli ◽  
M. I. Romano ◽  
J. A. Burdman

ABSTRACT Relationships among the release of prolactin, the effect of oestrogens and the proliferation of prolactin-secreting cells were studied under several experimental conditions. Administration of sulpiride or oestradiol released prolactin and stimulated cell proliferation in the anterior pituitary gland of adult male rats. Clomiphene completely abolished the rise in cell proliferation, but did not interfere with the sulpiride-induced release of prolactin. Treatment with oestradiol plus sulpiride significantly increased serum prolactin concentrations and the mitotic index compared with the sum of the stimulation produced by both drugs separately. Bromocriptine abolished the stimulatory effect of oestradiol on the serum prolactin concentration and on cell proliferation. In oestradiol- and/or sulpiride-treated rats, 80% of the cells in mitoses were lactotrophs. The remaining 20% did not stain with antisera against any of the pituitary hormones. The number of prolactin-secreting cells in the anterior pituitary gland significantly increased after the administration of oestradiol or sulpiride. The results demonstrate that treatment with sulpiride and/or oestradiol increases the proliferation and the number of lactotrophs in the anterior pituitary gland of the rat. J. Endocr. (1986) 108, 399–403


2018 ◽  
Vol 314 (1) ◽  
pp. R12-R21 ◽  
Author(s):  
Hershel Raff ◽  
Brian Hoeynck ◽  
Mack Jablonski ◽  
Cole Leonovicz ◽  
Jonathan M. Phillips ◽  
...  

Care of premature infants often requires parental and caregiver separation, particularly during hypoxic and hypothermic episodes. We have established a neonatal rat model of human prematurity involving maternal-neonatal separation and hypoxia with spontaneous hypothermia prevented by external heat. Adults previously exposed to these neonatal stressors show a sex difference in the insulin and glucose response to arginine stimulation suggesting a state of insulin resistance. The current study used this cohort of adult rats to evaluate insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR)], plasma adipokines (reflecting insulin resistance states), and testosterone. The major findings were that daily maternal-neonatal separation led to an increase in body weight and HOMA-IR in adult male and female rats and increased plasma leptin in adult male rats only; neither prior neonatal hypoxia (without or with body temperature control) nor neonatal hypothermia altered subsequent adult HOMA-IR or plasma adiponectin. Adult male-female differences in plasma leptin were lost with prior exposure to neonatal hypoxia or hypothermia; male-female differences in resistin were lost in the adults that were exposed to hypoxia and spontaneous hypothermia as neonates. Exposure of neonates to daily hypoxia without spontaneous hypothermia led to a decrease in plasma testosterone in adult male rats. We conclude that neonatal stressors result in subsequent adult sex-dependent increases in insulin resistance and adipokines and that our rat model of prematurity with hypoxia without hypothermia alters adult testosterone dynamics.


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