The Pineal Gland and the Effect of Neonatal Administration of Androgen upon the Development of Spontaneous Salt and Water Intake in Female Rats

1975 ◽  
Vol 18 (2) ◽  
pp. 137-143 ◽  
Author(s):  
J. Křeček ◽  
M. Pánek ◽  
J. Šalátová ◽  
J. Zicha
2021 ◽  
Vol 4 (1) ◽  
pp. 99-114
Author(s):  
Janaína B Garcia ◽  
Fernanda G Do Amaral ◽  
Daniela C Buonfiglio ◽  
Rafaela FA Vendrame ◽  
Patrícia L Alves ◽  
...  

The pineal gland synthesizes melatonin exclusively at night, which gives melatonin the characteristic of a temporal synchronizer of the physiological systems. Melatonin is a regulator of insulin activities centrally and also peripherally and its synthesis is reduced in diabetes.  Since monosodium glutamate (MSG) is often used to induce the type 2 diabetic and metabolic syndrome in animal models, the purpose of this work is to evaluate the potential effects of MSG given to neonates on the pineal melatonin synthesis in different aged male and female rats. Wistar rats were subcutaneously injected with MSG (4mg/g/day) or saline solution (0.9%) from the second to eighth post-natal day. The circadian profiles both melatonin levels and AANAT activity were monitored at different ages. Body weight, naso-anal length, adipose tissues weight, GTT, ITT and serum insulin levels were also evaluated. Typical obesity with the neonatal MSG treatment was observed, indicated by a great increase in adipose depots without a concurrent increase in body weight. MSG treatment did not cause hyperglycemia or glucose intolerance, but induced insulin resistance. An increase of melatonin synthesis at ZT 15 with phase advance was observed in in some animals. The AANAT activity was positively parallel to the melatonin circadian profile. It seems that MSG causes hypothalamic obesity which may increase AANAT activity and melatonin production in pineal gland. These effects were not temporally correlated with insulin resistance and hyperinsulinemia indicating the hypothalamic lesions, particularly in arcuate nucleus induced by MSG in early age, as the principal cause of the increase in melatonin production.


1970 ◽  
Vol 63 (4) ◽  
pp. 667-678 ◽  
Author(s):  
Russel J. Reiter

ABSTRACT The influence of early androgen treatment, light deprivation (by blinding), pinealectomy and superior cervical ganglionectomy on the reproductive system of female rats was tested. Early postnatal treatment of rats with testosterone propionate caused adult rats to exhibit the characteristic signs of androgen sterilization; these included polyfollicular ovaries, normal-sized uteri and persistent vaginal cornification. If early androgentreated rats also were blinded the ovaries were smaller in size and contained fewer follicles, the uteri were greatly reduced in size and the incidence of vaginal oestrus was decreased by approximately 50% If in addition to blinding, androgen-sterilized animals were subjected to either removal of the pineal gland or superior cervical ganglia, the reproductive organs and the vaginal smears were indistinguishable from those of testosterone-treated rats with eyes. These data indicate that the inhibitory influence of blinding on the pituitary-ovarian axis was mediated through the sympathetic nervous system and the pineal gland. The restraining influence of light deprivation on the growth of the reproductive organs was not permanent as illustrated by the fact that if these animals were kept to 120 days of age the ovaries and uteri grew to the same level as those of pinealectomized control rats.


1999 ◽  
Vol 276 (1) ◽  
pp. R90-R96 ◽  
Author(s):  
Lori R. Kisley ◽  
Randall R. Sakai ◽  
Li Yun Ma ◽  
Steven J. Fluharty

Spontaneous water intake as well as thirst elicited by ANG II has been shown to be influenced by the stage of the estrous cycle in the female rat. In these experiments, the contribution of each of the ovarian steroid hormones to the regulation of water intake was examined. Ovariectomized female rats were given replacement doses of estrogen, progesterone, or both, and their responsiveness to an intracerebroventricular injection of ANG II was tested. Forty-eight-hour treatment with estradiol benzoate attenuated ANG II-induced thirst by as much as 70% compared with control animals. The effect of estrogen on drinking was dose dependent and could be completely blocked with concurrent administration of the antiestrogen CI-628. In contrast, progesterone, given alone or after estrogen, did not significantly affect ANG II-induced water intake when animals were tested at 4 or 24 h after steroid administration. A central interaction between the peptide hormone ANG II and estrogen, involving a genomic mechanism, may underlie the cyclicity in water intake behavior observed in the rat.


2016 ◽  
Vol 0 (3 (3)) ◽  
pp. 14-18
Author(s):  
Вікторія Василівна Конопельнюк ◽  
Ірина Юріївна Прибитько ◽  
Олена Іванівна Цирюк ◽  
Тетяна Михайлівна Фалалєєва

1986 ◽  
Vol 61 (2) ◽  
pp. 780-784 ◽  
Author(s):  
E. H. Schlenker ◽  
M. Goldman

In this study ventilation was evaluated in 12-mo-old male and female rats who had received large doses of aspartic acid neonatally. Rats of both sexes treated with aspartic acid were obese, stunted, and exhibited hypogonadism. Although metabolic rates of the aspartic acid-treated rats were not different compared with sex-matched controls, ventilatory patterns were different. Aspartic acid-treated females breathed with a smaller tidal volume (VT), higher frequency (f), and similar minute ventilation (VE) compared with control females. This pattern is commonly observed in many patients who are obese. The aspartic acid-treated females responded to hypercapnic and hypoxic challenges by increasing f more than VT. Tissue pocket gases (PCO2 and PO2) of aspartic acid-treated females were normal. In contrast, aspartic acid-treated males hypoventilated compared with control males. Tissue pocket gas values suggested that aspartic acid-treated males were hypoxemic and hypercapnic. Moreover, the response of aspartic acid-treated males to hypercapnia was parallel to but was less than that of control male rats. The ventilatory response of aspartic acid-treated male rats to hypoxia was blunted. This study has shown that neonatal administration of aspartic acid causes a decreased ventilation and blunted response to hypoxia in adult male but not female rats.


1978 ◽  
Vol 56 (3) ◽  
pp. 465-470 ◽  
Author(s):  
M. J. Katovich ◽  
M. J. Fregly

Isoproterenol-induced thirst in rats has been attributed to the activation of β-adrenergic receptors. Since these receptors can be further differentiated pharmacologically into β1 and β2 types, experiments were performed using several β-adrenergic agonists and antagonists to determine the receptor type initiating the isoproterenol-induced thirst. The β1- and β2-adrenergic antagonist, d,l-propranolol (1 mg/kg, ip), blocked the increase in water intake usually accompanying acute subcutaneous administration of isoproterenol (25 μg/kg) to female rats. Since l-propranolol is known to stabilize membranes and to possess anesthetic-like properties, d-propranolol was also used. This isomer has little β-adrenergic-blocking activity but possesses anesthetic-like activity. Administration of d-propranolol (1 mg/kg, ip) failed to affect the drinking response to acute administration of isoproterenol (25 μg/kg). Practolol (125 mg/kg), a β1-adrenergic antagonist with little anesthetic properties, also had no effect on water intake of isoproterenol-treated rats. Butoxamine, a selective β2-adrenergic antagonist, attenuated the drinking response to isoproterenol. Salbutamol (150 μg/kg), a β2-adrenergic agonist, mimicked the effect of isoproterenol on water intake. These results are consistent with the suggestion that β2-adrenergic receptors mediate the isoproterenol-induced thirst in rats.


1978 ◽  
Vol 25 (4) ◽  
pp. 236-246 ◽  
Author(s):  
G.D. Gray ◽  
A.M. Bergfors ◽  
R. Levin ◽  
S. Levine

2009 ◽  
Vol 2 (2) ◽  
pp. 88-92 ◽  
Author(s):  
Vijay K. Bharti ◽  
R. S. Srivastava

The neuroendocrine functions of the pineal affect a wide variety of glandular and nervous system processes. Beside melatonin (MEL), the pineal gland secretes and expresses certain proteins essential for various physiological functions. It has been suggested that the pineal gland may also have an antioxidant role due to secretory product other than MEL. Therefore, the present study was designed to study the effect of buffalo (Bubalus bubalis) pineal proteins (PP) on the antioxidant defense system in the brain of female rats. The twenty-four rats were taken in present study and were divided into four groups: control (0 day), control (28 day), vehicle control and buffalo PP. The PP was injected 100 µg/kg BW intraperitoneal (i.p.) daily for 28 days. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR) and reduced glutathione (GSH) concentration and the levels of lipid peroxidation (LPO) in the brain tissue were measured to assess the antioxidant systems. These enzymes protect from adverse effects of free radicals and help in amelioration of oxidative stress. Buffalo pineal proteins administration did not cause any effect on brain LPO, whereas GPx, GR and GSH were significantly (p < 0.05) decreased. However, SOD and CAT activities were increased to significant levels than the control in PP treated rats. Our study herein suggested that buffalo (Bubalus bubalis) pineal proteins upregulates specific antioxidant defense systems and can be useful in control of various oxidative stress-induced neuronal diseases.


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