ICV porcine relaxin stimulates water intake but not sodium intake in male and female rats

SUMMARY Observations on water and electrolyte metabolism after hypophysectomy or adrenalectomy, in male and female rats with hereditary hypothalamic diabetes insipidus (Brattleboro strain) are confirmed and extended. The diabetic (homozygous, DI) state relative to the non-diabetic (heterozygous, non-DI) state was characterized by (1) water intake of 55–120% body weight; (2) copious urine hypo-osmotic to plasma; (3) greater excretory rates of total solute, Na, Ca and Mg; (4) similar plasma composition except that in male DI rats, K concentration was less, and in female DI rats osmolarity was higher; (5) glomerular filtration rates (GFR) were similar with close correlations between: food and water intakes, water intake and output, urinary Na and K, Na and CI, K and Cl, and Ca and Mg; (6) both female DI and non-DI rats had lower urinary Na: K ratios and lower plasma Na concentrations than males; (7) female DI rats excreted relatively larger amounts of K and Cl, and had higher plasma Ca concentrations than other groups. Hypophysectomized DI rats had decreased water intake and urine output, decreased solute excretion, decreased loss of osmotically free water, lower excretory rates of Na, K and Cl, and increased urinary osmolarity and K concentrations. Hypophysectomized non-DI rats had increased urinary excretory rates, decreased solute excretion (by 60–70%), decreased osmotically free water absorption, decreased urinary osmolarity, Na and K concentrations, and increased excretory rates of Ca and Mg. Hypophysectomized DI and non-DI rats had increased plasma osmolarity and Na concentration. Plasma renin activities (PRA) were higher in DI than in non-DI rats with female values lower than those of males; values for both sexes of DI and non-DI rats were reduced after hypophysectomy. Adrenalectomized DI rats had about a 50% reduction in water intake, urine output and free water clearance, increased urinary concentration of electrolytes and total solute by day 4 after operation; their Na balance (dietary:urine) did not change significantly in contrast to adrenalectomized non-DI rats in which a greater percentage of dietary Na appeared in the urine. GFR was similarly reduced in adrenalectomized DI and non-DI rats. Plasma osmolarity increased in adrenalectomized male DI, decreased in female DI and non-DI, and did not change in male non-DI rats. Plasma K concentrations increased after adrenalectomy in all groups, only non-DI rats had a significantly decreased plasma Na concentration. There was no sex difference in pituitary oxytocic activity but it was consistently reduced in DI rats; there was little change after adrenalectomy in male DI and non-DI rats; but there was an increase in DI and non-DI females. Pituitaries of DI rats had no measurable ADH activity (except the inherent activity of oxytocin). Pituitary ADH values for male and female non-DI rats were similar and were unaffected by adrenalectomy.

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COX2 inhibition during nephrogenic period induces ANG II hypertension and sex-dependent changes in renal function during aging

AJP Renal Physiology ◽

10.1152/ajprenal.00535.2013 ◽

2014 ◽

Vol 306 (5) ◽

pp. F534-F541 ◽

Cited By ~ 4

Author(s):

Virginia Reverte ◽

Antonio Tapia ◽

Analia Loria ◽

Francisco Salazar ◽

M. Teresa Llinas ◽

...

Keyword(s):

Sodium Intake ◽

Female Rats ◽

Ang Ii ◽

Functional Reserve ◽

Male And Female ◽

High Sodium ◽

Renal Response ◽

Renal Functional Reserve ◽

High Sodium Intake ◽

Male And Female Rats

This study was performed to test the hypothesis that ANG II contributes to the hypertension and renal functional alterations induced by a decrease of COX2 activity during the nephrogenic period. It was also examined whether renal functional reserve and renal response to volume overload and high sodium intake are reduced in 3–4- and 9–11-mo-old male and female rats treated with vehicle or a COX2 inhibitor during nephrogenic period (COX2np). Our data show that this COX2 inhibition induces an ANG II-dependent hypertension that is similar in male and female rats. Renal functional reserve is reduced in COX2np-treated rats since their renal response to an increase in plasma amino acids levels is abolished, and their renal ability to eliminate a sodium load is impaired ( P < 0.05). This reduction in renal excretory ability is similar in both sexes during aging but does not induce the development of a sodium-sensitive hypertension. However, the prolonged high-sodium intake at 9–11 mo of age leads to a greater proteinuria in male than in female (114 ± 12 μg/min vs. 72 ± 8 μg/min; P < 0.05) COX2np-treated rats. Renal hemodynamic sensitivity to acute increments in ANG II is unaltered in both sexes and at both ages in COX2np-treated rats. In summary, these results indicate that the reduction of COX2 activity during nephrogenic period programs for the development of an ANG II-dependent hypertension, reduces renal functional reserve to a similar extent in both sexes, and increases proteinuria in males but not in females when there is a prolonged increment in sodium intake.

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Effect of Hindlimb Unloading on Salt and Water Intake and Output in Male and Female Rats

Medicine & Science in Sports & Exercise ◽

10.1249/mss.0b013e31816a2450 ◽

2008 ◽

Vol 40 (7) ◽

pp. 1249-1254 ◽

Cited By ~ 2

Author(s):

HEATHER EDGELL ◽

SUSAN KAUFMAN

Keyword(s):

Water Intake ◽

Hindlimb Unloading ◽

Female Rats ◽

Male And Female ◽

Male And Female Rats

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THE PITUITARY AND ADRENAL RESPONSES TO ADMINISTRATION OF OESTRIOL IN GONADECTOMIZED RATS

Acta Endocrinologica ◽

10.1530/acta.0.0380050 ◽

1961 ◽

Vol 38 (1) ◽

pp. 50-58 ◽

Cited By ~ 3

Author(s):

N. E. Borglin ◽

L. Bjersing

Keyword(s):

Pituitary Gland ◽

Adrenal Cortex ◽

Clinical Experience ◽

Uterine Cervix ◽

Morphological Changes ◽

Physiological Significance ◽

Female Rats ◽

Experimental Conditions ◽

Male And Female ◽

Male And Female Rats

ABSTRACT Oestriol (oestra-1,3,5(10)-triene-3,16α,17β-triol) is a weakly oestrogenic substance which, however, in contrast to what was formerly believed, is of physiological significance. Its effect is localized largely to the uterine cervix and vagina. Clinical experience argues both for and against an effect on the pituitary gland. This investigation is concerned with the morphological changes in the pituitary gland and adrenal cortex of gonadectomized male and female rats after the injection of oestriol. It was found that oestriol has the same type of action on these glands as other oestrogens, but under the experimental conditions used, this effect proved much weaker than that produced by oestradiol (oestra-1,3,5(10)-triene-3,17β-diol).

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INDUCTION OF GOITRE BY PTU OR KClO4 IN MALE AND FEMALE RATS. EFFECT OF GONADECTOMY

Acta Endocrinologica ◽

10.1530/acta.0.0740088 ◽

1973 ◽

Vol 74 (1) ◽

pp. 88-104 ◽

Cited By ~ 2

Author(s):

T. Jolín ◽

M. J. Tarin ◽

M. D. Garcia

Keyword(s):

Iodine Content ◽

High Plasma ◽

Disc Electrophoresis ◽

Female Rats ◽

Male Rats ◽

Adult Rats ◽

Male And Female ◽

Glucose Levels ◽

Male And Female Rats ◽

Tsh Levels

ABSTRACT Male and female rats of varying ages were placad on a low iodine diet (LID) plus KClO4 or 6-propyl-2-thiouracil (PTU) or on the same diet supplemented with I (control rats). Goitrogenesis was also induced with LID plus PTU in gonadectomized animals of both sexes. The weight of the control and goitrogen treated animals, and the weight and iodine content of their thyroids were determined, as well as the plasma PBI, TSH, insulin and glucose levels. The pituitary GH-like protein content was assessed by disc electrophoresis on polyacrylamide gels. If goitrogenesis was induced in young rats of both sexes starting with rats of the same age, body weight (B.W.) and pituitary growth hormone (GH) content, it was found that both the males and females developed goitres of the same size. On the contrary, when goitrogenesis was induced in adult animals, it was found that male rats, that had larger B.W. and pituitary GH content than age-paired females, developed larger goitres. However, both male and female rats were in a hypothyroid condition of comparable degree as judged by the thyroidal iodine content and the plasma PBI and TSH levels. When all the data on the PTU or KClO4-treated male and female rats of varying age and B.W. were considered together, it was observed that the weights of the thyroids increased proportionally to B.W. However, a difference in the slope of the regression of the thyroid weight over B.W. was found between male and female rats, due to the fact that adult male rats develop larger goitres than female animals. In addition, in the male rats treated with PTU, gonadectomy decreased the B.W., pituitary content of GH-like protein and, concomitantly, the size of the goitre decreased; an opposite effect was induced by ovariectomy on the female animals. However, when goitrogenesis was induced in weight-paired adult rats of both sexes, the male animals still developed larger goitres than the females. Among all the parameters studied here, the only ones which appeared to bear a consistent relationship with the size of the goitres in rats of different sexes, treated with a given goitrogen, were the rate of body growth and the amount of a pituitary GH-like protein found before the onset of the goitrogen treatment. Moreover, though the pituitary content of the GH-like protein decreased as a consequence of goitrogen treatment, it was still somewhat higher in male that in female animals. The present results suggest that GH may somehow be involved in the mechanism by which male and female rats on goitrogens develop goitres of different sizes, despite equally high plasma TSH levels.

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THE UPTAKE AND LOCALIZATION OF 3H-OESTRADIOL IN THE HYPOTHALAMUS OF MALE AND FEMALE RATS

Acta Endocrinologica ◽

10.1530/acta.0.061s194 ◽

1969 ◽

Vol 61 (1_Suppl) ◽

pp. S194 ◽

Cited By ~ 1

Author(s):

Arne Attramadal

Keyword(s):

Female Rats ◽

Male And Female ◽

Male And Female Rats

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GONADOTROPHIN PATTERNS IN MALE AND FEMALE RATS:

Acta Endocrinologica ◽

10.1530/acta.0.0580600 ◽

1968 ◽

Vol 58 (4) ◽

pp. 600-612 ◽

Cited By ~ 1

Author(s):

Robert Boyd ◽

Donald C. Johnson

Keyword(s):

Ascorbic Acid ◽

Testosterone Propionate ◽

Female Rats ◽

Female Rat ◽

Feedback Effects ◽

Male And Female ◽

Prostate Weight ◽

Male And Female Rats ◽

Males And Females ◽

Normal Males

ABSTRACT The effects of various doses of testosterone propionate (TP) upon the release of luteinizing hormone (LH or ICSH) from the hypophysis of a gonadectomized male or female rat were compared. Prostate weight in hypophysectomized male parabiotic partners was used to evaluate the quantity of circulating LH. Hypophyseal LH was measured by the ovarian ascorbic acid depletion method. Males castrated when 45 days old secreted significantly more LH and had three times the amount of pituitary LH as ovariectomized females. Administration of 25 μg TP daily reduced the amount of LH in the plasma, and increased the amount in the pituitary gland, in both sexes. Treatment with 50 μg caused a further reduction in plasma LH in males, but not in females, while pituitary levels in both were equal to that of their respective controls. LH fell to the same low level in partners of males or females receiving 100 μg TP. When gonadectomized at 39 days, males and females had the same amount of plasma LH, but males had more stored hormone. Pituitary levels were unchanged from controls following treatment with 12.5, 25 or 50 μg TP daily, but plasma values dropped an equal amount in both sexes with the latter two doses. Androgenized males or females, gonadectomized when 39 days old, were very sensitive to the effects of TP and plasma LH was significantly reduced with 12.5 μg daily. Pituitary LH in androgenized males was higher than that of normal males but was reduced to normal by small amounts of TP. The amount of stored LH in androgenized females was not different from that of normal females and it was unchanged by any dose of TP tested. Results are consistent with the conclusion that the male hypothalamic-hypophyseal axis is at least as sensitive as the female axis to the negative feedback effects of TP. Androgenization increases the sensitivity to TP in both males and females.

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