• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.7
• /
• pp.1135-1141
• /
• 1999

A large number of investigations have shown that changes in nutritional condition affect endocrine status in avian species. Herein, recent findings including novel peptides discovered by the development of the techniques in the field of molecular biology have been reviewed. The insulin-like growth factors (IGF-I and IGF-II) found in chickens have been characterized and shown to be 70 and 66 amino acid polypeptides, respectively. Plasma IGF-I level is very responsive to nutrition, Le. varying dietary proteins and energy intakes, and food restriction. Plasma IGF-II concentration is altered by nutritional deprivation to a much smaller extent than plasma IGF-I concentration. Almost all of the serum and tissue IGFs are found in a complex composed of IGF and IGF-binding protein (IGFBP). In the chicken plasma, the major IGFBP differs from that in mammalian plasma. The proglucagon mRNA encodes glucagon and two glucagon-like peptides (GLP-I and GLP-2). The intracerebroventricular administration of GLP-l strongly decreased food intake of chicks, and it was indicated that the inhibition of food intake by GLP-l was associated with neuropeptide Y, which is one of the neurotransmitters reported to enhance food intake.

• The Korean Journal of Physiology and Pharmacology
• /
• v.3 no.2
• /
• pp.215-222
• /
• 1999

Nonylphenol (NP) is a widespread environmental pollutant that has been shown to exert both toxic and estrogenic effects on mammalian cells. As the effects of NP on the reproductive system of adult male vertebrates are virtually unknown, we investigated not only the changes of reproductive hormone secretion in serum after chronic exposure to NP but also, in order to identify the site of its action, the reproductive hormone secretion in serum 48 hours after microinfusion of NP within hypothalamic preoptic area (POA). In the chronic exposure, the luteinizing hormone (LH), follicle stimulating hormone (FSH), and testosterone in serum were decreased but prolactin (PRL) concentrations were increased. The LH, FSH, and testosterone in serum were decreased through the direct infusion of NP into POA, while there was no difference in mean serum prolactin between NP and control groups. These observations suggest that NP as endocrine disruptor has modulatory effects on hypothalamo-pituitary-gonadal axis and that the site of action of NP could be hypothalamic POA.

• Fisheries and Aquatic Sciences
• /
• v.16 no.3
• /
• pp.187-194
• /
• 2013

Microalgae are sensitive indicators of environmental changes, and hence they are widely used in environmental risk assessments and for the development of discharge guidelines. Here we evaluated the toxicity of metals and endocrine-disrupting chemicals (EDCs) to the marine green microalga, Tetraselmis suecica. The toxicants investigated included the metals, Cu, Ni, and Pb; and the EDCs, bisphenol A (BPA), endosulfan (ES), and polychlorinated biphenyl (PCB). The endpoints were variations in cell counts and chlorophyll a levels. T. suecica displayed a varied pattern of sensitivity to the toxicants. Based on the 72-h median effective concentration ($EC_{50}$), ES (0.045 mg/L) was most toxic to T. suecica, followed by PCB (3.96 mg/L) and Pb (9.62 mg/L). Interestingly, T. suecica was relatively tolerant to Cu (43.03 mg/L). The 72-h $EC_{50}$ values of Ni and BPA were approximately 16 mg/L. Our data suggest that this species may be relatively tolerant to most of the chemicals within their permissible limits in the environment.

• Toxicological Research
• /
• v.17 no.2
• /
• pp.115-121
• /
• 2001

Some of endocrine disruptors with sexual hormone-like effects have been increasingly reported to be immunotoxic in many species in recent several years. Phthalate esters have possible effects on the endocrine system. Prenatal exposure to di(n-butyl) phthalate (DBP) has been reported to impair the androgen-dependent development of the male reproductive tract in rat. Therefore, the immunomodulatory effect of DBP was investigated in the developing immune system of fetal and neonatal Sprague-Dawley rats. Timed-bred pregnant SD rats were given to the doses of 0, 250, 500, and 750 mg DBP/kg$\cdot$ body weight /day by gavage once a day from gestational day (GD) 5 to 18. On GD19 or GD22/postnatal day one (PD1), the dams were euthanized, and the changes in organ weights and thymus phenotypes were examined for their offsprings. At 750 mg DBP/kg$\cdot$b.w./day in maternal exposure group, GD19 fetuses showed decreases in body weight. The spleen/body weight ratios were reduced in GD 19 fetuses from the dams exposed to 500 and 750 mg DBP/kg$\cdot$b.w./day. There were no significant changes in thymus and spleen cellularities though these cellularities showed a tendency to decrease in a dose dependent way. In the DBP-exsposed GD22/PD1 offsprings, the body weights, the relative organ weights and the cellularities did not exhibit alteration. Additionally, the percentages of CD3$^{+}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) and CD3$^{-}$(CD4$^{+}$CD8$^{+}$, CD4$^{+}$CD8$^{-}$, CD4$^{-}$CD8$^{+}$, and CD4$^{-}$CD8$^{-}$) thymocyte subsets were not changed in any DBP-treated group. The proliferative responses of splenic T cells to Con A and B cells to LPS were decreased in all DBP-exposed GD22/PD1 offsprings.

• Korean Journal of Animal Reproduction
• /
• v.16 no.4
• /
• pp.377-385
• /
• 1993

This study was taken to examine correlationships between ehdocrine changes such as estradiol-17$\beta$, progesterone, T4 and T3 and serum components concentrations of female Oreochromis niloticus living in 0$\textperthousand$, 10$\textperthousand$, 20$\textperthousand$, and 30$\textperthousand$ salt concentrations, respectively. The results obtained in these experiments were summarized as follows. Correlation coefficients of serum albumin and thyroxine were ＋0.907 and ＋0.611 in 10$\textperthousand$ and 20$\textperthousand$, respectively. In 30$\textperthousand$ salinity, serum BUN and other 3 kinds of hormones showed all negative correlation coefficients. Correlation coefficients of serum estradiol-17$\beta$ with calcium and cholesterol in 20$\beta$ were ＋0.624, ＋0.733, respectively. Correlation coefficient between serum triglycerides and thyroxine in 30$\beta$ was ＋0.989.

• The Korean Journal of Physiology
• /
• v.16 no.2
• /
• pp.159-163
• /
• 1982

Vasoactive intestinal peptide (VIP) found in duodenal mucosa originally has been suggested as a neurotransmitter. Its localization, however, now known, is not limited to the gastrointestinal tract, but scattered at many different kinds of tissues, smooth muscles, endocrine gland and exocrine gland as well as central and peripheral neural tissues. To investigate the effect of VIP on renal function, an experiment has been done in anesthetized male rats. The results obtained were: 1) Urinary output and creatinine clearance decreased significantly during the period of infusion of VIP, 2.0ug/rat/7minutes. 2) Urinary excretion of sodium, potassium and chloride decreased but without significance by infusion of VIP. 3) Blood pressure, systolic and diastolic, decreased by VIP administered intravenously in the period of infusion. 4) Changes of urinary output, sodium and chloride excretion was correlated with changes of creatinine clearance. The above data suggest that VIP administered intravenously can suppress the renal hemodynamics indirectly, and also decrease electrolyte excretion through its renal hemodynamic change.

• Biomedical Science Letters
• /
• v.15 no.1
• /
• pp.25-29
• /
• 2009

The changes on the regional distributions and frequencies of somatostatin-immunoreactive (IR) cells in the fundus and pylorus of the stomach of osteoporotic Sprague-Dawley rats induced by ovariectomy were studied by immunohistochemical methods. The experimental animals were divided into two groups, one for non-ovariectomized group (Sham) and the other for ovariectomized group (OVX). Samples were collected from the fundus and pylorus regions at the 10 th week after ovariectomy or sham-operation. Somatostatin-IR cells were observed in both regions of the stomach regardless of ovariectomy. Most of these IR cells in the mucosa of the fundus or pylorus were generally spherical or spindle in shape (open type cell) while cells found in the gastric gland regions were round in shape (close type cell). Significantly lower number (P<0.01) of somatostatin-IR cells were detected in OVX as compared with Sham in the fundus and pylorus. In the present study, the density of somatostatin in the stomach was markedly decreased. Therefore, these changes in density of somatostatin-IR cells detected in this study may support the speculation that the development of gastrointestinal symptoms in osteoporosis such as impairments of calcium and some lipids, frequently encountered in patients with postmenopausal osteoporosis because the changes in gastrointestinal endocrine density would reflect the change in the capacity of producing these hormones and regulating gut motility and digestion.

• Korean Journal of Clinical Laboratory Science
• /
• v.44 no.1
• /
• pp.31-37
• /
• 2012

Many mammals in temperate zones are affected by the distinctive changes of the four seasons in these zones. Their reproductive status is active in the summer climate and inactive during severe winter weather. The golden hamster (Mesocricetus auratus) is seasonal breeding animal whose sexual activities are regulated by photoperoidism. The reproduction and metabolism are activated by long summer days (LD) and inhibited by short winter days (SD). After several months of SD, animals become refractory to this inhibitory photoperiod and spontaneously revert to LD-like physiology. The suprachiasmatic nuclei (SCN) house the primary circadian oscillator in mammals. Seasonal changes in the photic input to this structure control many annual physiological rhythms via SCN-regulated pineal melatonin secretion, which provides an internal endocrine signal representing photoperiod. The aim of this study was to assess the variation in the morphology of the testis in relation to the natural photoperiod in male golden hamsters. The hamsters were castrated at different weeks (2, 5, 8, and 15). The cell numbers of tubules with spermatogonia (SG), spermatocyte (SC), spermatids (ST), and spermatozoa (SZ) were recorded in each sample. The results showed that testicular regression of golden hamsters occurred in the SD-treated animals. The present investigation determines that the effects of the photoperiod on the reproduction of male golden hamsters. It was also found that the circadian period increases the rate of reproductive inhibition in animals exposed to inhibitory photoperiods.

• Development and Reproduction
• /
• v.26 no.1
• /
• pp.13-21
• /
• 2022

Neurokinin B (NKB) is a neuropeptide involved in the regulation of reproductive endocrine system of vertebrate animals, including fish. However, the pathway of NKB action in fish has not been clearly elucidated. In order to clarify the effect of NKB and NKF (neurokinin F) on gonadotropic hormone (GTH) gene expression in the pituitary, we studied the changes of LHβ and FSHβ gene expressions by using two different pituitary culture methods (whole pituitary culture or dispersed pituitary cell culture). Pituitaries were removed from mature female and male Nile tilapia. Changes of LHβ and FSHβ gene expressions were measured and compared after the treatment with NKB or NKF peptides at concentrations 0 to 1,000 nM. Expression of GTH genes in the whole pituitary cultures treated with NKB or NKF peptides did not show significant difference except in female at one concentration when treated with NKF. On the contrary, there were significant changes of GTH gene expressions in the dispersed pituitary cell cultures when treated with NKB and NKF peptides. These results suggest that dispersed pituitary cell culture is more relevant than whole pituitary culture in studying the function of pituitary, and that NKB and NKF could act directly on the pituitary to regulate the expression of GTH genes.

• CELLMED
• /
• v.12 no.1
• /
• pp.3.1-3.7
• /
• 2022

Background & Objectives: Polycystic ovarian syndrome (PCOS) is one of the commonest endocrine abnormality in women of reproductive age affecting from 4% - 21% of the reproductive women and is characterized by chronic anovulation and hyperandrogenism. The aim of the study was to evaluate the effect of majoon idraare haiz in menstrual regulation and morphological changes in ovaries in poly cystic ovarian syndrome. Methods: A Pilot study was carried out in the department of Ilmul qabalat wa amraze niswan, National institute of unani medicine, hospital, Bengaluru. Fifteen Patients of PCOS aged 18-35 diagnosed using Rotterdam criteria were included in the study. Patients with insulin sensitizing treatment within 3 months, hormonal treatment and those with h/o diabetes mellitus, hypertension, pregnant and lactating women were excluded.Majoon idraare haiz was administered orally at a dose of 10 g with 20 ml arqbed mushk once daily from fifth day of cycle for 21 days for three consecutive cycles. Primary outcome measure was menstrual regularity while changes in USG pelvis(normal ovarian morphology) was considered as secondary outcome measure. In addition, duration of flow and changes in basal metabolic index (BMI), modified Ferriman Gallwey (mFG) score, acanthosis nigricanswere observed. Data were analyzed using, ANOVA, paired student 't' test, fisher exact test. Results: Changes in duration of cycle, duration and amount of flow was achieved in 93.3% patients with p<0.0001 and 46.6% patients showed normal findings on pelvic ultrasonography with p=0.006. In addition, significant changes were also observed in BMI, hirsutism and acanthosis nigricans with p value of 0.0001, p=0.003 and p=0.009 respectively Conclusion: Majoonidraare haiz can be used as an effective alternative in management of PCOS patients. It has significant effect on menstrual regulation and changes in polycystic ovarian morphology to normal.