Pituitary Weight Research Articles

The adipokine profile in the plasma and anterior pituitary of pigs during the estrous cycle

Adipokines play crucial roles in both reproductive and energy metabolic processes. This study aimed to compare the hormonal plasma profile of adiponectin, apelin, vaspin, chemerin, resistin, visfatin, and adipolin, and the expression of their receptors in the anterior pituitary (AP) between normal-weight Large White (LW) and fat Meishan (MS) pigs during different phases of the estrous cycle. We measured adipokine levels in the plasma and assessed their gene expression in the AP. We used Pearson’s correlation analysis to examine potential links between adipokines levels, their receptors, and metabolic parameters (body weight; backfat thickness) and reproductive parameters (pituitary weight; age at puberty; levels of gonadotropins, steroid hormones; and gene expression of gonadotropin-releasing hormone receptor and gonadotropins in AP). The plasma levels of the evaluated adipokines fluctuated with phase and breed, except for visfatin and adipolin. Moreover, adipokine expression in AP varied significantly between breeds and estrous cycle phases, except for resistin receptor CAP1. Notably, we observed a positive correlation between plasma levels of adiponectin and its transcript in the AP only in MS pigs. Apelin gene expression correlated negatively with its receptor in MS, while we observed a breed-dependent correlation between chemerin gene expression and its receptor CMKLR1. We identified significant positive or negative correlations between adipokines or their receptor levels in plasma and AP as well as metabolic or reproductive parameters, depending on the breed. In conclusion, we have demonstrated breed-specific and estrous cycle-dependent regulation of adipokines in AP, underscoring their potential impact on metabolic and reproductive processes in swine.

A 28-Day Repeated Oral Administration Study of Mechanically Fibrillated Cellulose Nanofibers According to OECD TG407.

The impact of oral administration of mechanically fibrillated cellulose nanofibers (fib-CNF), a commonly used nanofiber, on toxicity and health remains unclear, despite reports of the safety and beneficial effects of chitin-based nanofibers. Thus, evaluating the oral toxicity of fib-CNF in accordance with OECD Test Guideline 407 (TG407) is essential. This study aimed to assess the safety of orally administered fib-CNF through an acute toxicity study in rats, following the OECD TG407 guidelines for 4 weeks. CNF "BiNFi-s" FMa-10005, derived from mechanically fibrillated pulp cellulose, was administered via gavage to male and female Crl:CD(SD) rats at doses of 50, 150, 500, and 1000 mg/kg/day for 28 days, with a control group receiving water for injection. The study evaluated the toxic effects of repeated administration, and the rats were monitored for an additional 14 days post-administration to assess recovery from any toxic effects. The results showed no mortality in either sex during the administration period, and no toxicological effects related to the test substance were observed in various assessments, including general condition and behavioral function observations, urinalysis, hematological examination, blood biochemical examination, necropsy findings, organ weights, and histopathological examination. Notably, only female rats treated with 1000 mg/kg/day of CNF exhibited a consistent reduction in body weight during the 14-day recovery period after the end of treatment. They also showed a slight decrease in pituitary and liver weights. However, hematological and blood biochemical tests did not reveal significant differences, suggesting a potential weight-suppressive effect of CNF ingestion.

Prenatal exposure to bisphenol A and/or diethylhexyl phthalate alters stress responses in rat offspring in a sex- and dose-dependent manner.

Background: Prenatal exposures to endocrine disrupting chemicals (EDCs) are correlated with adverse behavioral outcomes, but the effects of combinations of these chemicals are unclear. The aim of this study was to determine the dose-dependent effects of prenatal exposure to EDCs on male and female behavior. Methods: Pregnant Sprague-Dawley rats were orally dosed with vehicle, bisphenol A (BPA) (5μg/kg body weight (BW)/day), low-dose (LD) diethylhexyl phthalate (DEHP) (5μg/kg BW/day), high-dose (HD) DEHP (7.5mg/kg BW/day), a combination of BPA and LD-DEHP (B + D (LD)), or a combination of BPA and HD-DEHP (B + D (HD)) on gestational days 6-21. Adult offspring were subjected to the Open Field Test (OFT), Elevated Plus Maze (EPM), and Shock Probe Defensive Burying test (SPDB) in adulthood. Body, adrenal gland, and pituitary gland weights were collected at sacrifice. Corticosterone (CORT) was measured in the serum. Results: Female EDC-exposed offspring showed anxiolytic effects in the OFT, while male offspring were unaffected. DEHP (HD) male offspring demonstrated a feminization of behavior in the EPM. Most EDC-exposed male offspring buried less in the SPDB, while their female counterparts showed reduced shock reactivity, indicating sex-specific maladaptive alterations in defensive behaviors. Additionally, DEHP (LD) males and females and B + D (LD) females displayed increased immobility in this test. DEHP (LD) alone and in combination with BPA led to lower adrenal gland weights, but only in male offspring. Finally, females treated with a mixture of B + D (HD) had elevated CORT levels. Conclusion: Prenatal exposure to BPA, DEHP, or a mixture of the two, affects behavior, CORT levels, and adrenal gland weights in a sex- and dose-dependent manner.

O-249 Calcium directly influences pituitary function through the Calcium Sensing Receptor (CaSR)

Abstract Study question Does calcium have a direct effect on pituitary function through CaSR? Summary answer CaSR is important for Hypothalamus-pituitary-gonadal (HPG) axis signaling, and lack of CaSR in the anterior pituitary leads to smaller reproductive organs in female mice. What is known already In a randomized clinical trial, prepubertal children were given calcium supplementation or placebo and girls in the intervention group went into puberty 5 months earlier than the placebo group. This effect was not detected in the boys who participated. CaSR is the main receptor for systemic calcium homeostasis, and its presence has been established in the anterior pituitary. Study design, size, duration We performed a mouse study comparing knock-out mice with a deletion of the CaSR in the anterior pituitary to wildtype mice. 13/13 female and 6/13 male knock-out/controls mice were included in the study. Participants/materials, setting, methods Female and male knock-out and control mice were sacrificed at 8 weeks. We obtained blood samples and reproductive organs was dissected, weighted and stored at -80 °C or stored in formalin before being paraffin embedded. Main results and the role of chance Female reproductive organs showed significantly lower weight when comparing CaSR knock-out to control mice. This includes ovary weight (3.7 mg vs. 6.4 mg; p = 0.0004) and uterus weight (27.9 mg vs. 67.0 mg; p = 0.0008). The weight difference was still significant after correcting for total body weight (organ weight/total body weight%): (0.02176 vs. 0,03534; p = 0.0035 and 0.1788 vs. 0.3826; p = 0.0023 respectively). We did not observe a significant difference in male reproductive organs, nor any difference in pituitary weight in either sex. Limitations, reasons for caution The difference in reproductive organ weights is interesting, but it is also an early finding. Further analysis of the collected organs and blood samples will be conducted to further investigate the phenotype of the mouse model. We are also looking into correcting weight differences for estrous cycle effects. Wider implications of the findings If CaSR proves to be important for the regulation of the HPG-axis, it has a clinical perspective since CaSR can be modulated by the drug Cinacalcet, an allosteric agonist of CaSR, already on the market where it is used to treat kidney patients. Trial registration number Not applicable

Genetic background in the rat affects endocrine and metabolic outcomes of bisphenol F exposure.

Environmental bisphenol compounds like bisphenol F (BPF) are endocrine-disrupting chemicals (EDCs) affecting adipose and classical endocrine systems. Genetic factors that influence EDC exposure outcomes are poorly understood and are unaccounted variables that may contribute to the large range of reported outcomes in the human population. We previously demonstrated that BPF exposure increased body growth and adiposity in male N/NIH heterogeneous stock (HS) rats, a genetically heterogeneous outbred population. We hypothesize that the founder strains of the HS rat exhibit EDC effects that were strain- and sex-dependent. Weanling littermate pairs of male and female ACI, BN, BUF, F344, M520, and WKY rats randomly received either vehicle (0.1% EtOH) or 1.125 mg BPF/l in 0.1% EtOH for 10 weeks in drinking water. Body weight and fluid intake were measured weekly, metabolic parameters were assessed, and blood and tissues were collected. BPF increased thyroid weight in ACI males, thymus and kidney weight in BUF females, adrenal weight in WKY males, and possibly increased pituitary weight in BN males. BUF females also developed a disruption in activity and metabolic rate with BPF exposure. These sex- and strain-specific exposure outcomes illustrate that HS rat founders possess diverse bisphenol-exposure risk alleles and suggest that BPF exposure may intensify inherent organ system dysfunction existing in the HS rat founders. We propose that the HS rat will be an invaluable model for dissecting gene EDC interactions on health.

Aging and androgens: Physiology and clinical implications.

In men > ~35years, aging is associated with perturbations in the hypothalamus-pituitary-testicular axis and declining serum testosterone concentrations. The major changes are decreased gonadotropin-releasing hormone (GnRH) outflow and decreased Leydig cell responsivity to stimulation by luteinizing hormone (LH). These physiologic changes increase the prevalence of biochemical secondary hypogonadism-a low serum testosterone concentration without an elevated serum LH concentration. Obesity, medications such as opioids or corticosteroids, and systemic disease further reduce GnRH and LH secretion and might result in biochemical or clinical secondary hypogonadism. Biochemical secondary hypogonadism related to aging often remits with weight reduction and avoidance or treatment of other factors that suppress GnRH and LH secretion. Starting at age ~65-70, progressive Leydig cell dysfunction increases the prevalence of biochemical primary hypogonadism-a low serum testosterone concentration with an elevated serum LH concentration. Unlike biochemical secondary hypogonadism in older men, biochemical primary hypogonadism is generally irreversible. The evaluation of low serum testosterone concentrations in older men requires a careful assessment for symptoms, signs and causes of male hypogonadism. In older men with a body mass index (BMI) ≥ 30, biochemical secondary hypogonadism and without an identifiable cause of hypothalamus or pituitary pathology, weight reduction and improvement of overall health might reverse biochemical hypogonadism. For older men with biochemical primary hypogonadism, testosterone replacement therapy might be beneficial. Because aging is associated with decreased metabolism of testosterone and increased tissue-specific androgen sensitivity, lower dosages of testosterone replacement therapy are often effective and safer in older men.

ODP576 A pilot randomized clinical trial of intranasal oxytocin to promote weight loss in children, adolescents, and adults with hypothalamic obesity

Abstract Many individuals with brain tumors affecting the hypothalamus and pituitary gain weight excessively after tumor treatment. There is currently no FDA-approved treatment for this condition, which is called hypothalamic obesity. In animals and in some preliminary studies in humans, the hypothalamic hormone oxytocin impacts metabolism, and may be deficient in individuals with hypothalamic obesity. Therefore, we performed a randomized, double-blind, placebo-controlled, cross-over trial to test the effects of 8 weeks of intranasal administration of oxytocin as compared to placebo on body weight in children, adolescents, and young adults (ages 10-<35y) with excess weight gain related to hypothalamic/pituitary brain tumors (N=13). We did not detect an effect of oxytocin on body weight or other metabolic measures. Overall oxytocin appeared well-tolerated, with most side effects being mild and not different from placebo. Our pilot study yielded several other lessons. First, affected individuals have many other medical problems. Also, individuals with hypothalamic obesity also differ from each other with respect to factors that impact body weight (e. g., appetite and eating behavior) and thus future larger studies could test different individualized dosing strategies, combination therapies, and a wider scope of outcomes to examine further the potential value of oxytocin treatment in this disorder. Keywords: Craniopharyngioma, Hypothalamic Dysfunction, Hypothalamus, Obesity, Weight Loss. Presentation: No date and time listed

Polymorphism of the follicle stimulating hormone receptor does not impact reproductive performance or in-vitro embryo production in beef heifers

Assisted reproductive technologies are used to propagate desirable genetics in a shortened timeframe. Selected females undergo ovarian stimulation with the use of follicle stimulating hormone (FSH) to increase embryo recovery for subsequent transfer programs. The FSH receptor (FSHR) c.337 C > G variant was reported to have a reduction in viable embryo numbers in an ovarian stimulation protocol. We, therefore, hypothesized that FSHR c.337 C > G would result in reduced in-vitro blastocyst development. Beef heifers were genotyped and selected based on the c.337 C > G FSHR genotype (CC, CG, GG; n = 15–16/genotype). Estrus was synchronized with a Select Synch protocol and heifers were slaughtered 5 days after induced ovulation. Anterior pituitaries, serum and reproductive tracts were collected at slaughter for analysis. Cumulus oocyte complexes (COCs) were collected and pooled within genotype for in-vitro fertilization (IVF) and subsequent blastocyst development. No differences were observed in carcass weights, anterior pituitary weights, serum progesterone, corpus lutea weight, surface follicle counts, histological follicle counts or follicular fluid estradiol concentration (P > 0.1) due to FSHR genotype. Differences were observed for ovulation rates in the GG FSHR genotype group (P < 0.01). However, cleavage and blastocyst rates were not affected due to FSHR genotype (P > 0.1), following standard IVF protocols. The FSHR variant does not influence antral follicle counts, estradiol production, or in-vitro blastocyst development in beef heifers. The GG FSHR genotype had an increased ovulation rate, which may indicate a greater potential for twinning, but research with a larger population is warranted to support this hypothesis.

Beneficial Effects of Flaxseed and/or Mulberry Extracts Supplementation in Ovariectomized Wistar Rats.

Low endogenous estrogen action causes several injuries. Medicinal plants, such as flaxseed and mulberry, contain substances that have been shown to be effective to the organism. The aim was to verify the effects of flaxseed and/or mulberry extracts on ovariectomized Wistar rats. The animals received supplements of extracts and estrogen or saline by gavage for 60 days and were weighed weekly. Vaginal wash, blood, pituitary, uterus, liver, and kidneys were collected. Phenolic compounds and the antioxidant activity of the extracts, lipid profile, uric acid, liver enzymes, and pituitary weight were measured. Histomorphometric for uterine wall and histopathological analyses for liver and kidney were performed. Flaxseed and mulberry extracts showed great antioxidant activity and large amounts of phenolic compounds. The treatment with extracts had less weight gain, increased pituitary weight, the predominance of vaginal epithelial cells, and reduced TC, LDL-c and lipase activity, similar to estrogen animals. Estrogen or flaxseed + mulberry animals reduced VLDL-c and TAG. HDL-c, uric acid, and liver enzymes did not differ. Estrogen or extracts demonstrated trophic action on the endometrial thickness and have not shown hepatotoxicity or nephrotoxicity. We suggested the beneficial effects of flaxseed and mulberry extract as an alternative to reduce and/or prevent the negative effects caused by low estrogenic action.

Histopathological and immunohistochemical evaluation for detecting changes in blood hormone levels caused by endocrine disruptors in a 28-day repeated-dose study in rats.

Although measurements of blood hormone levels in rodent toxicological studies can provide important information on the mechanisms of toxicity and extrapolation to humans, there are several difficulties such as large individual differences and limited sample volume. To develop a more simplified method that does not depend solely on blood samples, we examined the possible application of immunohistochemistry for detecting endocrine disruptors in short-term studies. Aminotriazole (AMT), propylthiouracil (PTU), phenobarbital, aminoglutethimide (AGT), estradiol, and vitamin D3 were administered orally to 6-week-old male and female SD rats (five/group) for 28 days. Measurements of serum hormone levels revealed decreases in triiodothyronine (T3) and thyroxine (T4) in the AMT and PTU groups, an increase in thyroid stimulating hormone (TSH) in the AMT, PTU, and AGT groups, and an increase in adrenocorticotrophic hormone in the AGT group. Increased thyroid, pituitary, and adrenal gland weights; histopathological lesions, including follicular hypertrophy/hyperplasia, hypertrophy/vacuolation of anterior pituitary cells, and increased adrenocortical vacuolation were observed in association with the hormone level changes. Immunohistochemical analysis revealed a decreased T4 level in the thyroid gland of the AMT and PTU groups and an increased area of TSH positive immunostaining in the pituitary gland of the AMT, PTU, and AGT groups, consistent with the changes in serum T4 and TSH levels, respectively. These results suggest that histopathological analysis and immunohistochemistry for T4 and TSH might be useful and sensitive methods of detecting thyroid dysfunction, and that combining organ weight measurements is a reliable parameter of detecting endocrine disruptors.

Bioactive component of aqueous extract of Solanum melongena ameliorate estradiol valerate induced ovarian-pituitary dysfunctions in female Sprague–Dawley rats: Histomorphological and biochemical evidence

BackgroundEstradiol valerate (EV) is known to cause hypothalamic-pituitary dysregulation of the gonadotrophin-releasing hormone. This study focused on the impact of aqueous extract of Solanum melongena(SM) on EV-induced ovarian-pituitary dysfunction in female Sprague-Dawley rats. MethodsThirty-two healthy female Sprague Dawley rats weighing (8 weeks old; weight 150–200 g) were randomly divided into four groups of eight (n = 8) rats each. Group A received 2 ml of distilled water, Group B received a single dose of 4 mg/kg body weight (bwt) of EV (i.p), Group C received 500 mg/kg bwt SM extract orally and Group D received a single dose of 4 mg/kg bwt of EV (i.p) and 500 mg/kg bwt of SM orally, the experiment lasted for 21days. The following parameters body weight, pituitary gland weight, ovary weight, ovary, and pituitary gland histomorphology, total antioxidant status (TOS), total oxidant status (TOS), oxidative stress index (OSI), total cholesterol (TC), triglyceride, low-density lipoprotein (LDL), and high-density lipoprotein (HDL), progesterone, FSH, LH, Testosterone, and estradiol were assessed. ResultsEstradiol valerate decreases the number of healthy follicles, progesterone, estradiol, HDL, and TAS. And increase degenerated cystic follicles, TT, FSH, LH, triglyceride, TC, LAL, TOS, and OSI. Pituitary gland showed degenerative changes, characterized by neutrophil infiltrations and loss of cellular projections marked improvement was observed in the ovary, pituitary gland, hormone, and biochemical parameters after SM administration. ConclusionSolanum melongena offers protection against EV-induced ovarian-pituitary dysfunctions evidence by restoration of oxidative stress markers, steroidogenesis, and histopathological alterations back to control level.

Endocrine, metabolic and apical effects of in utero and lactational exposure to non-dioxin-like 2,2′,3,4,4′,5,5′-heptachlorobiphenyl (PCB 180): A postnatal follow-up study in rats

PCB 180 is a persistent and abundant non-dioxin-like PCB (NDL-PCB). We determined the developmental toxicity profile of ultrapure PCB 180 in developing offspring following in utero and lactational exposure with the focus on endocrine, metabolic and retinoid system alterations. Pregnant rats were given total doses of 0, 10, 30, 100, 300 or 1000 mg PCB 180/kg bw on gestational days 7−10 by oral gavage, and the offspring were sampled on postnatal days (PND) 7, 35 and 84. Decreased serum testosterone and triiodothyronine concentrations on PND 84, altered liver retinoid levels, increased liver weights and induced 7-pentoxyresorufin O-dealkylase (PROD) activity were the sensitive effects used for margin of exposure (MoE) calculations. Liver weights were increased together with induction of the metabolizing enzymes cytochrome P450 (CYP) 2B1, CYP3A1, and CYP1A1. Less sensitive effects included decreased serum estradiol and increased luteinizing hormone levels in females, decreased prostate and seminal vesicle weight and increased pituitary weight in males, increased cortical bone area and thickness of tibial diaphysis in females and decreased cortical bone mineral density in males. Developmental toxicity profiles were partly different in male and female offspring, males being more sensitive to increased liver weight, PROD induction and decreased thyroxine concentrations. MoE assessment indicated that the 95th percentile of current maternal PCB 180 concentrations do not exceed the estimated tolerable human lipid-based PCB 180 concentration. Although PCB 180 is much less potent than dioxin-like compounds, it shares several toxicological targets suggesting a potential for interactions.

Evaluation of Prenatal Transportation Stress on the Number of Pituitary Corticotrophs in Mature Brahman Cows

Abstract Prenatal transportation stress (PNS) results in calves that are more temperamental and have greater circulating concentrations of cortisol compared to control calves. The objective of this experiment was to evaluate whether PNS alters the number of pituitary corticotrophs in mature Brahman cows. We hypothesized that the increased circulating cortisol concentrations previously characterized in this bovine model is associated with developmental changes in the anterior pituitary leading to an increased number of corticotrophs. Pregnant Brahman cows (n = 48) were transported in trailers for 2-hour periods at 60±5, 80±5, 100±5, 120±5, and 140±5 days of gestation. Non-transported pregnant cows (n = 48) were designated as the Control group. Control and PNS offspring heifers were managed together under the same environmental conditions. At approximately 5 yr of age, randomly selected non-pregnant cows (Control, n = 8; PNS, n = 6) were humanely harvested and the whole pituitaries were collected. Pituitaries were weighed, fixed in paraformaldehyde, serially dehydrated with graded ethanol, embedded in paraffin blocks, and cut into 5-μm sections. Immunohistochemistry was performed to detect cells expressing adrenocorticotropic hormone (ACTH) as a marker for corticotrophs. Three comparable sections from the midsagittal plane from each animal were processed using an ovine ACTH-specific antibody (Dr. A.F. Parlow, NIDDK). Five fields of view were analyzed per section (15 fields per animal). Anterior pituitary gland weight did not differ (P &amp;gt; 0.10) between groups (Control = 2.11 ± 0.12 g; PNS = 2.10 ± 0.15 g). The mean number of ACTH-positive cells between control (531±56 cells/section) and PNS cows (477±49 cells/section) also did not differ (P &amp;gt; 0.10). In conclusion, the number of pituitary corticotrophs in mature Brahman cows was not affected by prenatal transportation stress and is likely not a mechanism mediating the increased circulating cortisol concentrations seen in this bovine model of fetal programming.

Maternal nutrient restriction in late pregnancy programs postnatal metabolism and pituitary development in beef heifers

Maternal undernutrition during pregnancy followed by ad libitum access to nutrients during postnatal life induces postnatal metabolic disruptions in multiple species. Therefore, an experiment was conducted to evaluate postnatal growth, metabolism, and development of beef heifers exposed to late gestation maternal nutrient restriction. Pregnancies were generated via transfer of in vitro embryos produced using X-bearing sperm from a single Angus sire. Pregnant dams were randomly assigned to receive either 100% (control; n = 9) or 70% (restricted; n = 9) of their total energy requirements from gestational day 158 to parturition. From post-natal day (PND) 301 until slaughter (PND485), heifers were individually fed ad libitum in a Calan gate facility. Calves from restricted dams were lighter than controls at birth (P<0.05) through PND70 (P<0.05) with no difference in body weight from PND105 through PND485 (P>0.10). To assess pancreatic function, glucose tolerance tests were performed on PND315 and PND482 and a diet effect was seen with glucose area under the curve being greater (P<0.05) in calves born to restricted dams compared to controls. At slaughter, total internal fat was greater (P<0.05) in heifers born to restricted dams, while whole pituitary weight was lighter (P<0.05). Heifers from restricted dams had fewer growth hormone-positive cells (somatotrophs) compared to controls (P<0.05). Results demonstrate an impaired ability to clear peripheral glucose in heifers born to restricted dams leading to increased deposition of internal fat. A reduction in the number of somatotrophs may contribute to the adipogenic phenotype of heifers born to restricted dams due to growth hormone’s known anabolic roles in growth, lipolysis, and pancreatic islet function.

Early post-natal life stress induces permanent adrenocorticotropin-dependent hypercortisolism in male mice.

It has been hypothesized that specific early-life stress (ES) procedures on CD-1 male mice produce diabetes-like alterations due to the failure of negative feedback of glucocorticoid hormone in the pituitary. The aim of this study is to investigate the possible mechanism that leads to this pathological model, framing it in a more specific clinical condition. Metabolic and hypothalamic-pituitary-adrenal-related hormones of stressed mice (SM) have been analyzed immediately after stress procedures (21 postnatal days, PND) and after 70 days of a peaceful (unstressed) period (90 PND). These data have been compared to parameters from age-matched controls (CTR), and mice treated during ES procedures with oligonucleotide antisense for pro-opiomelanocortin (AS-POMC). At 21 PND, SM presented an increased secretion of hypothalamic CRH and pituitary POMC-derived peptides, as well as higher plasmatic levels of ACTH and corticosterone vs. CTR. At 90 PND, SM showed hyperglycemia, with suppression of hypothalamic CRH, while pituitary and plasmatic ACTH levels, as well as plasma corticosterone, were constantly higher than in CTR. These values are accompanied by a progressive acceleration in gaining total body weight, which became significant vs. CTR at 90 PND together with a higher pituitary weight. Treatment with AS-POMC prevented all hormonal and metabolic alterations observed in SM, both at 21 and 90 PND. These findings show that these specific ES procedures affect the negative glucocorticoid feedback in the pituitary, but not in the hypothalamus, suggesting a novel model of ACTH-dependent hypercortisolism that can be prevented by silencing the POMC gene.

Functional Restoration of Pituitary after Pituitary Allotransplantation into Hypophysectomized Rats.

Long-term hormone replacement therapy due to panhypopituitarism can lead to serious complications and thus, pituitary transplantation is considered a more desirable. We investigated functional restoration after allotransplatation of the pituitary gland. We transplanted extracted pituitary gland into the omentum of an hypophysectomized rat. Two experiments were performed: (1) to confirm the hypophysectomy was successful and (2) to assess functional restoration after pituitary transplantation. Pituitary hormone level and weight change were consecutively assessed. Electron microscopic (EM) examinations were performed to identify morphological changes at 3 days after transplantation. We confirmed that pituitary gland was properly extracted from 6 rats after sacrifice. The findings showed (1) a weight loss of more than 3% or (2) a weight change of less than 2% along with a decreased growth hormone (GH) level by more than 80% at 2 weeks post-hypophysectomy. A further four rats underwent pituitary transplantation after hypophysectomy and were compared with the previously hypophysectomized rats. All showed rapid weight gain during the two weeks after transplantation. The thyroid-stimulating hormone, prolactin, and GH levels were restored at one week post-transplantation and maintained for 10 weeks. Hypophyseal tissue architecture was maintained at 3 days after transplantation, as indicated by EM. These data suggest that a transplanted pituitary gland can survive in the omentum with concomitant partial restoration of anterior pituitary hormones.

Effect of Age and Season on the Growth of some Endocrine and Lympho-Epithelioid Glands in Nigerian and White Leghorn Pullets

THE endocrine glands (pituitary, adrenal, thyroid), and thymus and bursa of Fabricius of Nigerian und White Leghorn pullets were studied from 2 weeks to 32 weeks of age in the wet and dry seasons of Nigeria. Pituitary weights were significantly (P &lt;0.005) greater in the wet season-reared than in the dry season — reared birds. Adrenal weight differences due to breed were significant, but had no significant influence on this parameter, Nigerian pullets had significantly (P &lt;0.005) greater thyroid Weights (absolute and relative) than the Leghorns, and the absolute weights were also significantly (P &lt;0.05) higher in the wet that in the dry season. The differences in thymus weights between breeds and seasons were not significant but the interaction between season and age, and between breed and age were highly significant (P &lt; 0.005). The relative thymus weights were generally and significantly greater (P ... 0.0005, in the Nigerian than in the Leghorn pullets. The interaction between age and season and between breed and age were also highly significant [P &lt;0.005] in respect to the bursa. The effect of season and breed on the growth of the bursa was also highly significant (p &lt;0.005). The possible significance of these findings in relation to the general physiology of the two breeds of chicken were discussed.&#x0D;

Clinical care of the geriatric horse

Background: Geriatric horses account for a significant proportion of the UK horse population and therefore age‐related conditions are commonly encountered in equine practice.Aim of the article: This review aims to provide an overview of the practical approach to managing osteoarthritis, pituitary pars intermedia dysfunction, dental disease, weight loss and nutrition and colic in geriatric horses.

86 Evaluation of the effect of prenatal transportation stress on endocrine and immune tissues of neonatal Brahman calves

Abstract The objective of this experiment was to evaluate whether prenatal transportation stress (PNS) affects the weight of endocrine and immune tissues of calves. Mature Brahman cows inseminated to a single Brahman sire in 2018 were assigned to be either Control (n = 35; not transported) or PNS (n = 37; 2 h of transportation at 60, 80, 100, 120, and 140 ± 5 d of gestation). Of the calves born in 2019, 16 Control (8 bulls and 8 heifers) and 16 PNS (8 bulls and 8 heifers) calves were studied. Pen score, body weight, and blood samples were obtained from calves at 25 ± 2 d of age. At that time, calves were euthanized by barbiturate overdose in order to collect tissues (brain, pituitary and adrenal glands, spleen and thymus). Tissues were trimmed and weighed. Serum cortisol was determined by RIA. Data were analyzed using ANOVA, GLM, and CORR procedures of SAS with body weight at sample collection as a covariate. Whole pituitary weight tended (P = 0.08) to be greater in females compared to males, whereas anterior pituitary weight tended (P = 0.06) to be greater in PNS. Whole brain weight was greater (P &amp;lt; 0.01) in males. The interaction of treatment and sex on whole brain weight of PNS tended (P = 0.09) to fall between that of the Control females and Control males. Whole pituitary weight was positively correlated with total adrenal weight (r = 0.32; P = 0.08). Total thymus weight positively correlated with whole brain and total adrenal weight (r = 0.43 and 0.41, respectively; P &amp;lt; 0.05). Serum cortisol was negatively correlated with spleen weight and total immune tissue weight (r = -0.37 and -0.38, respectively; P &amp;lt; 0.05). Results suggest next steps should include a closer look at function of immune tissues by studying PNS effect on thymus response to immunization.

Developmental programming: gestational testosterone excess disrupts LH secretion in the female sheep fetus

BackgroundPrenatal testosterone (T) excess results in reproductive and metabolic perturbations in female sheep that closely recapitulate those seen in women with polycystic ovary syndrome (PCOS). At the neuroendocrine level, prenatal T-treated sheep manifest increased pituitary sensitivity to GnRH and subsequent LH hypersecretion. In this study, we investigated the early effects of gestational T-treatment on LH secretion and pituitary function in the female sheep fetus. Additionally, because prenatal T effects can be mediated via the androgen receptor or due to changes in insulin homeostasis, prenatal co-treatment with an androgen antagonist (flutamide) or an insulin sensitizer (rosiglitazone) were tested.MethodsPregnant sheep were treated from gestational day (GD) 30 to 90 with either: 1) vehicle (control); 2) T-propionate (~ 1.2 mg/kg); 3) T-propionate and flutamide (15 mg/kg/day); and 4) T-propionate and rosiglitazone (8 mg/day). At GD 90, LH concentrations were determined in the uterine artery (maternal) and umbilical artery (fetal), and female fetuses were euthanized. Pituitary glands were collected, weighed, and protein level of several key regulators of LH secretion was determined.ResultsFetal pituitary weight was significantly reduced by prenatal T-treatment. Flutamide completely prevented the reduction in pituitary weight, while rosiglitazone only partially prevented this reduction. Prenatal T markedly reduced fetal LH concentrations and flutamide co-treatment partially restored LH to control levels. Prenatal T resulted in a marked reduction in LH-β protein level, which was associated with a reduction in GnRH receptor and estrogen receptor-α levels and an increase in androgen receptor. With the exception of androgen receptor, flutamide co-treatment completely prevented these alterations in the fetal pituitary, while rosiglitazone largely failed to prevent these changes. Prenatal T-treatment did not alter the protein levels of insulin receptor-β and activation (phosphorylation) of the insulin signaling pathways.ConclusionsThese findings demonstrate that prenatal T-treatment results in reduced fetal LH secretion, reduced fetal pituitary weight, and altered protein levels of several regulators of gonadotropin secretion. The observations that flutamide co-treatment prevented these changes suggest that programming during fetal development likely occurs via direct androgen actions.