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1.
Acta Endocrinol (Buchar) ; 16(4): 426-436, 2020.
Article in English | MEDLINE | ID: mdl-34084233

ABSTRACT

CONTEXT: The grey mullet, Mugil cephalus, is an edible fish of high economic importance. Breeding biology with reference to hormonal/growth factor regulation of oocyte maturation needs to be known for its commercial production. OBJECTIVE: The present study was conducted to examine the potency of maturation inducing hormones, chorionic gonadotropin (hCG), bovine-insulin, and insulin like growth factor1 (h-IGF-1) I on ovarian steroidogenesis and oocyte maturation. DESIGN: The role of hormones and growth factors on steroidogenesis and oocyte maturation was investigated using specific inhibitors, Wortmannin for phosphatidylinositol-3 (PI3) kinase, trilostane for 3ß-hydroxysteroid dehydrogenase, 1-octanol and 1-heptanol for gap junctions, actinomycin D for transcription and cycloheximide for translation of signal molecules. METHODS: Actions of hormonal and growth factors were examined for steroidogenesis, by radioimmunoassay and oocyte maturation by germinal vesicle breakdown (GVBD). Specific inhibitors were used to determine the cell signaling pathways, PI3 kinase. RESULTS: All the inhibitors attenuated the hCG-induced oocyte maturation (GVBD%), steroidogenesis including transcription, translation, gap junctions and PI3 kinase signaling. These inhibitors failed to inhibit h-IGF-I and b-insulin-induced oocyte maturation, steroidogenesis, translation and PI3 kinase signaling. CONCLUSION: hCG induces oocyte maturation via steroid dependent pathway involving gap junctions, transcription, translation and PI3 kinase signaling, unlike h-IGF-I and b-insulin in the mullet.

2.
Arch Physiol Biochem ; 126(1): 7-16, 2020 Feb.
Article in English | MEDLINE | ID: mdl-30145920

ABSTRACT

Arecoline is known to cause endocrine dysfunction. In the current article role of arecoline on pineal-testis activity was investigated in hypothyroid rats induced by propylthiouracil (PTU). PTU treatment caused thyroid dysfunction ultrastructurally with a fall in T3 and T4 levels followed by a rise of thyroid stimulating hormone (TSH) level. Pineal activity was impaired by PTU treatment, as evident from degenerated synaptic ribbons and mitochondria of the pinealocytes with depletion of pineal and serum N-acetyl serotonin and melatonin levels. Leydig cell function was suppressed, evident from reduced smooth endoplasmic reticulum and depletion of testosterone level. Sex accessories function was impaired by showing scanty rough endoplasmic reticulum with depletion of fructose and sialic acid levels. Arecoline treatment that caused pineal dysfunction and testicular stimulation in control rats, suppressed both pineal and testis functions after PTU treatment. The findings suggest that arecoline inhibits pineal-testis function in experimentally induced hypothyroid rats.


Subject(s)
Antithyroid Agents/adverse effects , Arecoline/adverse effects , Hypothyroidism/chemically induced , Pineal Gland/drug effects , Propylthiouracil/adverse effects , Testis/drug effects , Thyroid Gland/drug effects , Animals , Endoplasmic Reticulum/drug effects , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/ultrastructure , Fructose/metabolism , Hypothyroidism/metabolism , Hypothyroidism/physiopathology , Leydig Cells/drug effects , Leydig Cells/metabolism , Leydig Cells/pathology , Male , Melatonin/blood , N-Acetylneuraminic Acid/metabolism , Pineal Gland/metabolism , Pineal Gland/physiopathology , Rats , Serotonin/analogs & derivatives , Serotonin/blood , Testis/metabolism , Testis/physiopathology , Testosterone/blood , Thyroid Gland/metabolism , Thyroid Gland/physiopathology , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
3.
Arch Physiol Biochem ; 126(3): 214-224, 2020 Jul.
Article in English | MEDLINE | ID: mdl-30318934

ABSTRACT

Arecoline has biomedical importance, but it has untoward side effects on endocrine functions. The aim is to investigate its role on adrenal activity under thermal stress by ultrastructural and hormonal parameters in mice. Cold (4 °C) or heat (37 °C) stress, or arecoline (10 mg/kg body wt), each for 7 days in cold or heat stress stimulated adrenocortical activity ultrastructurally with an elevation of corticosterone level. Adrenomedullary activity was suppressed in cold stress with depletion of catecholamine levels. In heat stress, adrenomedullary activity was stimulated ultrastructurally with an elevation of catecholamine levels. Arecoline treatment alone, or in cold or heat stress suppressed adrenomedullary activity, judged by ultrastructural and hormonal parameters. Arecoline treatment caused hypoglycemia with an elevation of glycogen level, but cold or heat stress, or arecoline treatment in thermal stress caused hyperglycemia, with a fall in glycogen profile. Thus, arecoline in thermal stress plays a dual role on adrenal function and glucose-glycogen homeostasis in mice.


Subject(s)
Adrenal Glands/drug effects , Arecoline/pharmacology , Cholinergic Agonists/pharmacology , Glucose/chemistry , Glycogen/chemistry , Kidney/physiology , Adrenal Glands/physiology , Animals , Blood Glucose/analysis , Catecholamines/blood , Cold Temperature , Corticosterone/blood , Epinephrine/pharmacology , Homeostasis , Hot Temperature , Hypoglycemia , Liver/metabolism , Male , Mice , Norepinephrine/pharmacology , Temperature
4.
Arch Physiol Biochem ; 124(5): 436-441, 2018 Dec.
Article in English | MEDLINE | ID: mdl-29278926

ABSTRACT

Betel nut of Areca catechu is chewed by millions of people for increased capacity to work and stress reduction, but it contains arecoline that causes hypothyroidism. The aim is to investigate the role of arecoline on thyroid activity in cold stress in mice. Arecoline treatment (10 mg/kg body wt/day, for 7 d) caused a reduction in thyroid weight and ultrastructural degeneration of thyro-follicular cells with depletion of T3 and T4 levels compared with the control mice. Cold stress (4 °C for 2 h, twice daily, for 7 d) stimulated thyroid activity ultrastructurally with an elevation of T3 and T4 levels. Arecoline treatment in cold stress suppressed thyroid activity by showing reversed changes to those of cold stress. In contrast, TSH concentrations were consistently increased under all experimental conditions. The findings suggest that cold stress causes hyperthyroidism which arecoline can ameliorate in mice.


Subject(s)
Arecoline/therapeutic use , Cholinergic Agonists/therapeutic use , Cryoprotective Agents/therapeutic use , Hyperthyroidism/prevention & control , Thyroid Gland/drug effects , Animals , Arecoline/adverse effects , Cholinergic Agonists/adverse effects , Cold-Shock Response/drug effects , Cryoprotective Agents/adverse effects , Enzyme-Linked Immunosorbent Assay , Hyperthyroidism/etiology , Hyperthyroidism/pathology , Hyperthyroidism/physiopathology , Hypothyroidism/chemically induced , Hypothyroidism/metabolism , Hypothyroidism/pathology , Hypothyroidism/physiopathology , Male , Mice , Microscopy, Electron, Transmission , Organ Size/drug effects , Reproducibility of Results , Thyroid Gland/metabolism , Thyroid Gland/physiopathology , Thyroid Gland/ultrastructure , Thyrotropin/blood , Thyrotropin/metabolism , Thyroxine/blood , Thyroxine/metabolism , Triiodothyronine/blood , Triiodothyronine/metabolism
5.
Arch Physiol Biochem ; 124(1): 18-26, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28704075

ABSTRACT

Millions of people consume betel nut for increased capacity to work and for stress reduction. The nut contains arecoline, which has multiple side effects on endocrine functions. Objective of the work is to investigate pineal-testicular responses to noise and after arecoline treatment in noise in rats. Noise exposure (100 dB, 6 h daily, 10 days) caused pineal stimulation ultrastructurally and at indoleamines level. Leydig cell dysfunction with fall of testosterone level and suppression of sex accessories were noticed. In contrast, pineal activity was inhibited and reproductive functions were stimulated after arecoline administration, confirmed from reversed changes to those of noise. Arecoline treatment in noise exposure showed same results as in noise both in pineal and in reproductive functions. It is concluded that noise causes testicular dysfunction probably by gonadotropin suppression induced by pineal melatonin in noise. Furthermore, arecoline cannot prevent it in noise in rats.


Subject(s)
Arecoline/therapeutic use , Endocrine System Diseases/prevention & control , Noise/adverse effects , Pineal Gland/drug effects , Protective Agents/therapeutic use , Testicular Diseases/prevention & control , Testis/drug effects , Animals , Arecoline/administration & dosage , Biomarkers/blood , Biomarkers/metabolism , Cell Nucleus/drug effects , Cell Nucleus/radiation effects , Cell Nucleus/ultrastructure , Cholinergic Agonists/therapeutic use , Endocrine System Diseases/etiology , Endocrine System Diseases/pathology , Endocrine System Diseases/physiopathology , Injections, Intraperitoneal , Leydig Cells/drug effects , Leydig Cells/metabolism , Leydig Cells/radiation effects , Leydig Cells/ultrastructure , Male , Microscopy, Electron, Transmission , Mitochondria/drug effects , Mitochondria/radiation effects , Mitochondria/ultrastructure , N-Acetylneuraminic Acid/metabolism , Pineal Gland/physiopathology , Pineal Gland/radiation effects , Pineal Gland/ultrastructure , Protective Agents/administration & dosage , Rats, Wistar , Seminal Vesicles/drug effects , Seminal Vesicles/metabolism , Seminal Vesicles/physiopathology , Seminal Vesicles/radiation effects , Testicular Diseases/etiology , Testicular Diseases/pathology , Testicular Diseases/physiopathology , Testis/physiopathology , Testis/radiation effects , Testis/ultrastructure , Testosterone/metabolism
6.
Acta Endocrinol (Buchar) ; 14(2): 175-183, 2018.
Article in English | MEDLINE | ID: mdl-31149255

ABSTRACT

CONTEXT: Betel nut is consumed by millions of people for stress reduction and increased capacity to work. One of its components is arecoline which is useful for Alzheimer and schizophrenia; it also influences endocrine and gonadal functions. OBJECTIVE: Objective is to examine whether arecoline can influence pineal-testicular function in metabolic stress. DESIGN: Rats were deprived of food or water or treated them with arecoline, each separately for 5 days. SUBJECTS: Pineal and testis with sex accessories were studied. METHODS: Ultrastructural (pineal, testis, Leydig cells and prostate), hormonal (melatonin and testosterone) and other parameters (fructose and sialic acid) were examined. Pineal indoleamines were quantitated by fluorometric method; testosterone by ELISA, and carbohydrate fractions by spectrophotometric methods. RESULTS: Inanition/ water deprivation caused pineal stimulation ultrastructurally (with enlarged synaptic ribbons) and elevation of melatonin level, but reproductive dysfunction by ultrastructural degeneration of Leydig cells and prostate with fall of testosterone, fructose and sialic acid concentrations. Arecoline treatment showed reversed changes to those of metabolic stress, but arecoline treatment in metabolic stress showed same results as in metabolic stress. CONCLUSION: The findings suggest that arecoline cannot alter the action of metabolic stress on pineal-testicular activity in rats.

7.
Acta Endocrinol (Buchar) ; 13(4): 400-409, 2017.
Article in English | MEDLINE | ID: mdl-31149208

ABSTRACT

BACKGROUND: People chew betel nut (Areca catechu) for physical work and stress reduction, but it contains arecoline, which has both therapeutic value and untoward effects on endocrine and gonadal functions. OBJECTIVE: Aim of the present study is to investigate its role on adrenal with its target in metabolic stress in mice. MATERIALS AND METHODS: Mice were deprived of water / food, each for 5 days / treated with arecoline (10 mg / kg body wt daily for 5 days) / arecoline after water or food deprivation, for 5 days each. RESULTS: Water or food-deprivation caused adrenocortical hyperactivity, evident from abundance of enlarged mitochondria and smooth endoplasmic reticulum (SER) with elevation of corticosterone level (C: 68.31 ± 2.30, WD: 159.31 ± 4.10 / FD: 194.12 ± 3.40 µg/ mL). Arecoline treatment alone or in water deprivation (C: 68.31 ± 2.30, AR: 144.50 ± 4.33, AR+WD: 194.42 ± 3.35 µg/ mL) / food deprivation (AR + FD: 180.89 ± 4.51 µg/ mL) stress also stimulated adrenocortical activity as recorded in metabolic stress. In contrast, adrenomedullary activity was not altered following water/ food deprivation. Arecoline treatment alone or in metabolic stress suppressed adrenomedullary activity by showing depletion of chromaffin granules (E/NE?), epinephrine (E) and norepinephrine (NE) concentrations. Both the stress decreased blood glucose and liver glycogen levels. Arecoline treatment decreased blood glucose level, with a rise in liver glycogen level, but elevated blood glucose level in water deprivation unlike in starvation. CONCLUSION: Arecoline alone or in metabolic stress involves adrenal and probably other endocrine glands (pancreas, posterior pituitary and rennin-angiotensin system) to maintain homeostasis in metabolic stress in mice.

8.
Arch Physiol Biochem ; 123(2): 105-111, 2017 May.
Article in English | MEDLINE | ID: mdl-28019102

ABSTRACT

Millions of people consume betel nut for increased capacity of work. It contains arecoline which is highly toxic and has several untoward side effects on endocrine functions. In this article, the role of arecoline on thyroid function under metabolic stress was investigated in mice. Water or food-deprivation, each for 5 days, caused ultrastructural degeneration of thyro-follicular cells, evident from pycnotic nuclei, scanty rough endoplasmic reticulum and mitochondria followed by depletion of blood serum T3 and T4 levels with alteration of TSH level as compared with control. Thyroid activity was also suppressed ultrastructurally as well as at hormonal level after arecoline administration. Further, arecoline treatment in water deprivation or food deprivation stress also caused thyroid dysfunction beyond that of metabolic stress, as evident from further ultrastructural degeneration of thyrocytes and depletion of thyroid hormones in mice. The findings suggest that arecoline aggravates hypothyroid condition in metabolic stress in mice.


Subject(s)
Arecoline/toxicity , Cholinergic Agonists/toxicity , Hypothyroidism/chemically induced , Hypothyroidism/metabolism , Stress, Physiological/drug effects , Animals , Hypothyroidism/pathology , Male , Mice , Microscopy, Electron, Transmission , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
9.
Fish Physiol Biochem ; 40(1): 105-16, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23925891

ABSTRACT

In this article, an in vitro investigation was carried out to ascertain the roles of hormones and growth factor in the inductions of oocyte maturation and steroidogenesis of the postvitellogenic follicles in an Indian estuarine grey mullet, Mugil cephalus L. Oocyte maturation was evaluated by scoring the germinal vesicle breakdown (GVBD) percent of the postvitellogenic follicles. All the sex [17α,20ß-dihydroxy-4-pregnane-3-one (DHP), estradiol 17ß (E2), progesterone (P), 17α-OH progesterone (17-OH-P) and testosterone] and other [bovine-insulin and salmon-calcitonin, human chorionic gonadotropin (hCG), luteinizing hormone (LH) or hCG+DHP] hormones and insulin-like growth factor-I (IGF-I) significantly increased GVBD% in 9 h culture. DHP had a maximum effect (75 %) compared to other effectors. Some effectors (hCG: 82.14 %, LH: 78.94 %, hCG plus DHP: 81.81 %, E2: 80 % and IGF-I: 74.19 %) including DHP (79 %) further increased GVBD% in 15-h culture. All the hormones (except DHP) and IGF-I increased DHP, E2 and testosterone productions by the postvitellogenic ovarian follicles in vitro. DHP and testosterone productions were increased with the increase of incubation time from 9 h through 15 h. E2 production was not further increased beyond 12 h. DHP production was highest by hCG compared to other effectors. The hCG of all the test compounds was most effective in both the induction of GVBD% and steroid production. DHP is the most potent inducer of oocyte maturation in Indian estuarine flat head grey mullet. Involvement of estrogen in mullet oocyte maturation is indicated. hCG, like DHP, is equally potent and induces oocyte maturation via DHP production in vitro. hCG with DHP has synergistic action on oocyte maturation in mullet ovary. Interplay of several hormones (hCG, LH, and probably E2 and testosterone) and IGF-I on oocyte maturation is suggested in the mullet.


Subject(s)
Fishes/physiology , Gonadal Steroid Hormones/physiology , Gonadotropins/physiology , Intercellular Signaling Peptides and Proteins/physiology , Oocytes/growth & development , Ovary/physiology , Animals , Aquaculture , Calcitonin/physiology , Female , Insulin/physiology , Insulin-Like Growth Factor I/physiology , Oocytes/metabolism , Ovary/cytology , Ovary/metabolism
10.
Mol Cell Endocrinol ; 319(1-2): 1-7, 2010 May 05.
Article in English | MEDLINE | ID: mdl-20085799

ABSTRACT

Arecoline is a plant alkaloid of betel nut Areca catechu. Arecoline has immunosuppressive, hepatotoxic, mutagenic and teratogenic effects, and disturbs some endocrine organs in rats. The objective is to investigate the untoward effects of arecoline on the thyroid gland in mice. Intraperitoneal injection of arecoline (10 mg/kg body weight only once) increased the serum T(3) and T(4) levels and decreased the serum TSH 20, 40 or 60 min after the treatment, with maximum effect at 40 min. Chronic arecoline treatment (10 mg/kg body weight daily for 15 days) caused light microscopic and ultrastructural degenerations of thyro-follicular cells with depletion of T(3) and T(4) levels followed by the elevation of the TSH level. Atropine (arecoline antagonist) injection prevented the changes (hyperactivity) induced by acute (40 min) arecline treatment. Arecoline initially stimulates thyroid activity, and eventually inhibits the activity; atropine prevents thyroid dysfunction induced by arecoline. Arecoline action is mediated probably via muscarinic cholinergic receptor-hypothalamic-pituitary-thyroid axis in mice.


Subject(s)
Arecoline/pharmacology , Thyroid Gland/drug effects , Thyroid Gland/metabolism , Thyroid Gland/ultrastructure , Analysis of Variance , Animals , Atropine/pharmacology , Cell Size/drug effects , Cholinergic Agonists/pharmacology , Cholinergic Antagonists/pharmacology , Epithelial Cells/cytology , Epithelial Cells/drug effects , Male , Mice , Microscopy, Electron, Transmission , Thyrotropin/blood , Thyroxine/blood , Triiodothyronine/blood
11.
Endocr Res ; 33(3): 119-27, 2008.
Article in English | MEDLINE | ID: mdl-19156570

ABSTRACT

The objective of the current investigation was to study adrenomedullary and glycemic responses to stress in soft-shelled turtles, Lissemys p. punctata. Dehydration (7 days) and formalin (formaldehyde 1%, 0.1 mL/100 g body wt. daily for 7 days) stress-stimulated adrenomedullary activity at histological (by increasing the nuclear diameter and degranulation of chromaffin cells) and hormonal levels (by elevations of norepinephrine and epinephrine concentrations) with hyperglycemia in turtles. But salt loading (NaCl: 1%, 1 mL/100 g body wt. daily for 7 days) had no significant effect on adrenomedullary activity or glycemia presumably owing to the nonresponsiveness of adrenocortical activity to salt stress in turtles. It is suggested that dehydration and formalin stresses might have exerted their actions through the hypothalamo (CRF)-hypophysial (ACTH)-adrenocortical axis in turtles.


Subject(s)
Adrenal Medulla/physiopathology , Blood Glucose/metabolism , Stress, Physiological/physiology , Turtles/physiology , Adrenal Medulla/drug effects , Animals , Chromaffin Cells/cytology , Dehydration/physiopathology , Epinephrine/blood , Female , Formaldehyde/pharmacology , Norepinephrine
12.
Acta Biol Hung ; 59(4): 403-12, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19133497

ABSTRACT

The current study was undertaken to ascertain the effects of diverse stress on thyroid activity in soft-shelled turtles, Lissemys punctata punctata. The findings revealed that starvation (10 days), dehydration (10 days) or exposure to electric shock (12 volts for 15 seconds at an interval of 30 min for 3 h) caused significant decrease in the body weight (except in electric shock), relative weight, peripheral and central epithelial heights of the follicles and peroxidase activity of the thyroid gland of turtles. The degree of change in the values of these parameters was nearly same in all the stress experiments, indicating that there is not much difference in the degree of thyroid responses to diverse stress in turtles. It is suggested that these stressors might have exerted their actions on thyroid activity presumably indirectly via adrenal medulla and/or substance in metabolic stress (starvation and dehydration) and via hypothalamo-hypophysial-adrenocortical axis in non-metabolic stress (electric shock) in Lissemys turtles.


Subject(s)
Thyroid Gland/physiopathology , Turtles/physiology , Animals , Dehydration/pathology , Dehydration/physiopathology , Electroshock , Female , Iodide Peroxidase/metabolism , Starvation/pathology , Starvation/physiopathology , Stress, Physiological/physiology , Thyroid Gland/pathology , Turtles/anatomy & histology
13.
J Exp Zool A Ecol Genet Physiol ; 307(4): 187-98, 2007 Apr 01.
Article in English | MEDLINE | ID: mdl-17436329

ABSTRACT

Arecoline is an alkaloid of betel nut of Areca catechu. Betel nut is chewed by millions of people in the world and it causes oral and hepatic cancers in human. It has therapeutic value for the treatment of Alzheimer and schizophrenia. Arecoline has immunosuppressive, mutagenic and genotoxic effects in laboratory animals. It also affects endocrine functions. The objective of this study was to investigate the effects of arecoline on pineal-testicular axis in rats. Since pineal activity is different between day and night, the current study is undertaken in both the photophase and scotophase. The findings were evaluated by ultrastructural and hormonal studies of pineal and testicular Leydig cells, with quantitations of fructose and sialic acid of sex accessories. Arecoline treatment (10 mg/kg body weight daily for 10 days) caused suppression of pineal activity at ultrastructural level by showing dilatation of the cisternae of the rough endoplasmic reticulum (RER), large autophagosome-like bodies with swollen mitochondrial cristae, numerous lysosomes, degenerated synaptic ribbons and reduced number of synaptic-like microvesicles. Moreover, pineal and serum N-acetylserotonin and melatonin levels were decreased with increased serotonin levels in both the gland and serum. In contrast, testicular Leydig cell activity was stimulated with abundance of smooth endoplasmic reticulum (SER), electron-dense core vesicles and vacuolated secretory vesicles, and increased testosterone level in the arecoline recipients. Consequently, the testosterone target, like prostate, was ultrastructurally stimulated with abundance of RER and accumulation of secretory vesicles. Fructose and sialic acid concentrations were also significantly increased respectively in the coagulating gland and seminal vesicle. These results were more significant in the scotophase than the photophase. The findings suggest that arecoline inhibits pineal activity, but stimulates testicular function (testosterone level) and its target organs presumably via muscarinic cholinergic receptor in rats.


Subject(s)
Arecoline/pharmacology , Cholinergic Agonists/pharmacology , Pineal Gland/metabolism , Pineal Gland/ultrastructure , Testis/metabolism , Testis/ultrastructure , Animals , Arecoline/administration & dosage , Cholinergic Agonists/administration & dosage , Fructose/metabolism , Injections, Intraperitoneal , Leydig Cells/drug effects , Leydig Cells/metabolism , Leydig Cells/ultrastructure , Male , Melatonin/metabolism , N-Acetylneuraminic Acid/metabolism , Photoperiod , Pineal Gland/drug effects , Prostate/drug effects , Prostate/metabolism , Prostate/ultrastructure , Rats , Rats, Wistar , Serotonin/analogs & derivatives , Serotonin/metabolism , Testis/drug effects , Testosterone/metabolism
14.
Acta Biol Hung ; 58(1): 11-9, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17385540

ABSTRACT

The aim of the current investigation was to investigate the effect of photoperiod on thyroid activity in soft-shelled turtles (Lissemys punctata punctata). Thirty days exposure of short photoperiod with 2L:22D increased relative weight, follicular epithelial height and peroxidase activity of the thyroid gland; whereas exposure of long photoperiod with 22L:2D for 30 days showed reversed changes to those of the short photoperiod in adult female turtles. These findings indicate that short photoperiod stimulates thyroid activity and long photoperiod inhibits its activity in soft-shelled turtles. It is suggested that photoperiod exerts its action on thyroid activity presumably via gonads and/or pineal-gonadal axis in turtles.


Subject(s)
Photoperiod , Thyroid Gland/physiology , Animals , Body Weight , Epithelial Cells/cytology , Feeding Behavior , Hypertrophy , India , Iodide Peroxidase/metabolism , Organ Size , Thyroid Gland/pathology , Turtles/anatomy & histology
15.
Toxicology ; 227(1-2): 94-104, 2006 Oct 03.
Article in English | MEDLINE | ID: mdl-16945459

ABSTRACT

BACKGROUND: There are about 600 million betel quid chewers in the world. Betal quid chewing is one of the major risk factors of hepatocarcinoma, oropharyngeal and esophagus cancers. Arecoline, the main Areca alkaloid of the betel nut is reported to have cytotoxic, genotoxic and mutagenic effects in various cells. It shows strong correlation to the incidence of oral submucosal fibrosis, leukoplakia and oral cancer, and has also been found to impose toxic manifestations in immune, hepatic and other defense systems of the recipient. AIM: The precise molecular mechanisms underlying the toxic effects of arecoline deserve investigation. To clarify the action of arecoline on defense systems, immune, hepatic and detoxification system were studied in mice. METHOD: Cell count and cell cycle of the splenocytes were studied for evaluating cell immunity. Liver function test (LFT) was followed by assaying different enzyme systems from serum (SGPT, SGOT and ALP) and liver (GST for detoxication enzyme, SOD and catalase for antioxidant enzymes and GSH for non-enzymatic antioxidant) and by ultrastructural studies of hepatocytes. RESULTS: Here we report that arecoline arrested splenic lymphocyte cell cycle at lower concentration with induced apoptosis at higher concentration thereby causing immunosuppression in arecoline recipients. Besides, it resulted in hepatotoxicity in arecoline recipient mice by disrupting the hepatocyte ultrastructure, as judged by liver ultrastructural studies that showed decreased nuclear size, RER with profusely inflated cysternae and abundance of lipid droplets, and by up regulating hepatotoxic marker enzymes (SGOT and SGPT) in serum. Arecoline also caused depression of antioxidants, i.e., superoxide dismutase (SOD), catalase, reduced glutathione (GSH) and glutathione-S-transferase (GST) that are known to neutralize reactive oxygen species. CONCLUSION: All these above-mentioned results led us to conclude that arecoline attacks multiple targets to finally generate systemic toxicity in mice.


Subject(s)
Antioxidants/metabolism , Arecoline/toxicity , Chemical and Drug Induced Liver Injury , Liver , Spleen , Animals , Cell Cycle/drug effects , Chemical and Drug Induced Liver Injury/etiology , Chemical and Drug Induced Liver Injury/immunology , Chemical and Drug Induced Liver Injury/metabolism , DNA/metabolism , Immunity, Cellular/drug effects , Liver/drug effects , Liver/metabolism , Liver/ultrastructure , Lymphocytes/cytology , Lymphocytes/drug effects , Lymphocytes/metabolism , Mice , Microscopy, Electron, Transmission , Spleen/cytology , Spleen/drug effects , Spleen/immunology
16.
Folia Biol (Krakow) ; 54(3-4): 93-102, 2006.
Article in English | MEDLINE | ID: mdl-17220003

ABSTRACT

The effects of some exogenous peripheral hormones (thyroxine, corticosterone, epinephrine, norepinephrine and insulin) on thyroid activity were investigated in juvenile female soft-shelled turtles, Lissemys punctata punctata. Each hormone was injected in three different doses (25 microg, 50 microg or 100 microg each per 100 g body weight, once daily at 9 AM) for 10 consecutive days. Thyroid activity was evaluated by gravimetry, histology (epithelial height) and thyroperoxidase assay. The findings revealed that thyroxine in low dose (25 microg) stimulated thyroid activity by increasing the relative thyroid weight, epithelial height and thyroperoxidase activity, but inhibited gland activity at a high dose (100 microg) by decreasing the values of all these parameters. The medium dose (50 microg) had no significant effect. All other hormones, in all doses, significantly decreased thyroid activity by decreasing the values of all the parameters. Thyroid responses to exogenous hormones are generally dose-dependent in turtles. The mechanisms of actions of the hormones administered are suggested.


Subject(s)
Adrenal Cortex Hormones/physiology , Pancreatic Hormones/physiology , Thyroid Gland/physiology , Thyroid Hormones/physiology , Turtles/physiology , Animals , Female , Iodide Peroxidase/metabolism , Organ Size , Thyroid Gland/enzymology
17.
Folia Biol (Krakow) ; 52(1-2): 73-80, 2004.
Article in English | MEDLINE | ID: mdl-15521652

ABSTRACT

The aim of the current investigation was to ascertain the role of ACTH and adrenal hormones on adrenomedullary and glycemic functions in soft-shelled turtles, Lissemys punctata punctata. All the experiments were carried out on sexually immature animals. Findings revealed that: (1) ACTH administration (0.5 IU/1.0 IU/2.0 IU per 100 g body wt. daily for 10 days) in all doses stimulated adrenomedullary function by increasing medullary cell nuclear diameter with elevations of norepinephrine, epinephrine and blood sugar levels. Only moderate and higher doses (50 microg/100 microg per 100 g body wt. daily for 10 days) of dexamethasone suppressed adrenomedullary activity and blood sugar level by reversing the changes to those of ACTH; the responses were dose-dependent. But these changes were no longer observed after ACTH treatment in dexamethasone (DMS) recipients (DMS: 100 microg/ 100 g body wt daily for the first 10 days and ACTH: 0.5 IU / 100 g body wt daily for the next 10 days); (2) Only moderate and higher doses (50 microg/100 microg per 100 g body wt daily for 10 days) of corticosterone increased adrenomedullary activity and blood sugar level and the responses were also dose-dependent. But aldosterone treatment in all doses (same as for corticosterone) had no significant effect on the adrenal medulla or blood sugar level; (3) Only moderate and higher doses of norepinephrine or epinephrine (same as for corticosterone) caused adrenomedullary atrophy with depletions of norepinephrine and epinephrine levels but elevated the glycemic level. The findings are briefly discussed.


Subject(s)
Adrenal Medulla/drug effects , Blood Glucose/drug effects , Turtles/metabolism , Adrenal Medulla/cytology , Adrenocorticotropic Hormone/administration & dosage , Adrenocorticotropic Hormone/pharmacology , Aldosterone/administration & dosage , Aldosterone/pharmacology , Analysis of Variance , Animals , Cell Nucleus/ultrastructure , Corticosterone/administration & dosage , Corticosterone/pharmacology , Dose-Response Relationship, Drug , Epinephrine/administration & dosage , Epinephrine/pharmacology , Female , India , Norepinephrine/administration & dosage , Norepinephrine/pharmacology
18.
Indian J Exp Biol ; 42(6): 620-5, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15260116

ABSTRACT

Adrenocortical responses to diverse stressful situations (dehydration, formaldehyde treatment and salt loading) were studied in the adult female soft-shelled turtle, Lissenmys p. punctata. Dehydration, formaldehyde treatment (formalin, 1%: 0.1 ml/100 g body weight daily) or salt loading (NaCl, 1%: 0.1 ml/100 g body weight daily) treatments consecutively for 7 days caused hypertrophy of the adrenocortical cells with their nuclear diameter increased, and depletions of adrenal cholesterol and ascorbic acid concentrations followed by decreased acid phosphatase and alkaline phosphatase activities in turtles. Corticosterone levels were elevated in both the adrenal gland and serum of turtles after dehydration and formalin stress, but the hormone level remained unaltered after salt loading in turtles. The results suggest active involvement of adrenal cortex in stress for homeostasis in Lissemys turtles.


Subject(s)
Adrenal Cortex/metabolism , Acid Phosphatase/metabolism , Alkaline Phosphatase/metabolism , Animals , Ascorbic Acid/metabolism , Body Weight , Cholesterol/metabolism , Corticosterone/metabolism , Dehydration , Female , Formaldehyde/metabolism , Formaldehyde/pharmacology , Homeostasis , Salts/pharmacology , Stress, Physiological , Turtles
19.
Indian J Exp Biol ; 41(8): 880-4, 2003 Aug.
Article in English | MEDLINE | ID: mdl-15248489

ABSTRACT

An exposure to ambient temperature of 25 degrees C had no perceptible effect on interrenal function but further increase of temperature to 35 degrees C caused nuclear hypertrophy with increase of nuclear diameter, RNA concentration, acid phosphatase and alkaline phosphatase activities, accompanied by quantitative depletions of cholesterol (free, esterified and total) and ascorbic acid levels in the interrenal gland of the soft-shelled turtle Lissemys p. punctata. Similar manifestations of stimulation, except in the nucleus, were marked after exposure to 38 degrees C, but the degree of response in respect of esterified and free cholesterol levels was higher at 38 degrees C than at 35 degrees C. Moreover, withdrawal of 38 degrees C temperature and subsequently maintaining at 25 degrees C for 15 days showed reverse manifestations to those of 35 degrees C/38 degrees C, leading to a tendency towards normalcy. It is suggested that high a ambient temperature of 35 degrees C significantly stimulates interrenal function of Lissemys turtles, but further increase of 38 degrees C does not cause further overall stimulation, and withdrawal of higher temperature (38 degrees C) shows a tendency towards normalcy. It is also suggested that (a) high ambient temperature causes thermal stress, (b) it is reversible and (c) it acts on interrenal activity presumably via CRF-ACTH-axis in turtles.


Subject(s)
Behavior, Animal/physiology , Hot Temperature , Interrenal Gland/physiology , Turtles/physiology , Acid Phosphatase/metabolism , Animals , Ascorbic Acid/metabolism , Cholesterol/metabolism , Female , Interrenal Gland/anatomy & histology , Interrenal Gland/metabolism
20.
Arch Physiol Biochem ; 111(3): 246-53, 2003 Jul.
Article in English | MEDLINE | ID: mdl-14972747

ABSTRACT

The aim of the current study was to investigate lithium action on adrenomedullary and adrenocortical functions and on serum ionic balance in rats. Three age-groups of male rats (juvenile: 30 days, adult: 100 days and aged: 3 years) were used. Each age-group of animal was exposed to short- (10 days) and long-term (25 days) treatments with lithium. Each age-group of rat received lithium at a dose 2mEq/kg body weight daily for 10 and 25 days. Each daily dose (2mEq) was divided equally into half (1 mEq) and each half was injected intraperitoneally twice (at 9 am and 9 pm) for both the durations of experiments. Control animals received physiological saline for similar duration of experiments. Thirty animals were used for each age-group and they were divided equally into 6 groups with 5 each. After termination of all the experiments rats were sacrificed and, adrenal glands were quickly dissected out and processed for epinephrine, norepinephrine and corticosterone estimations and, 3 beta-hydroxysteroid dehydrogenase (3 beta-HSDH) activity of the adrenal gland. Blood was drawn from the heart of each rat and, serum was collected and stored at -20 degrees C until assayed for lithium, calcium, sodium, potassium and corticosterone concentrations. The findings revealed that lithium in both short- and long-term treatments was maintained well within the therapeutic range (0.3-0.8 mEq/l) in all the age-groups of rats. This alkali metal caused depletions of both epinephrine and norepinephrine concentrations from adrenal glands, and elevations of corticosterone in both adrenal and blood serum of each age-group of rat (juvenile, adult and aged). Additionally adrenal 3beta-HSDH activity was also increased in all the age-groups of rats irrespective of duration of the treatments. Short-term treatment of lithium elevated only serum K+ level in juvenile and adult rats and, Ca+ level only in adult animals. Significant elevations of serum K+ and Ca+ levels were observed following long-term treatments of lithium in all the age group of rats. No significant change in serum Na+ level was recorded after lithium treatment, irrespective of duration of treatments, in any age-group of rats. The findings suggest that lithium action, in respect of adrenomedullary and adrenocortical functions and, serum ionic balance, may not be largely related to the age-group of rats and that, lithium acts on adrenomedullary activity probably by stimulating the release mechanism of epinephrine and norepinephrine from the adrenal gland of rats, but stimulates adrenocortical activity by stimulating both synthesis (including 3 beta-HSDH activity) and release of corticorterone. Simultaneously, lithium disturbs normal ionic balance by elevating K+ and Ca+ levels in all the age-group of rats. Thus, the antimanic drug certainly disturbs both adrenomedullary and adrenocortical functions and, serum ionic balance in all the age-group of rats.


Subject(s)
Adrenal Cortex/drug effects , Adrenal Cortex/physiology , Adrenal Medulla/drug effects , Adrenal Medulla/physiology , Lithium/pharmacology , Water-Electrolyte Balance/drug effects , 3-Hydroxysteroid Dehydrogenases/metabolism , Adrenal Cortex/metabolism , Adrenal Medulla/metabolism , Age Factors , Animals , Calcium/blood , Epinephrine/metabolism , Lithium/blood , Male , Norepinephrine/metabolism , Potassium/blood , Rats , Sodium/blood
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