Castration fails to prevent prenatally programmed hypertension in male rats

Lori L. Woods, Terry Morgan, John A. Resko

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

Male offspring of rats that were modestly protein restricted during pregnancy become hypertensive as adults, whereas their female littermates remain normotensive. The purpose of this study was to determine the role of testosterone in promoting this sexual dimorphism of prenatally programmed hypertension. Rats were fed either a normal (19% protein, NP) or modestly protein-restricted (8.5% protein, LP) diet throughout pregnancy. Male offspring either remained intact or were castrated (CAS) at 30 days of age. Female offspring remained intact. At ∼22 wk of age, the offspring were chronically instrumented for measurement of mean arterial pressure and renal function. Intact male LP offspring were hypertensive compared with male NP offspring (138 ± 2 vs. 130 ± 2 mmHg, P <0.007), whereas female LP offspring were normotensive (123 ± 1 vs. 122 ± 2 mmHg in NP females). In CAS males, blood pressure in both diet groups was not different from that in intact males of the same group (138 ± 3 mmHg in LP CAS males, and 131 ± 2 mmHg in NP CAS males). Glomerular filtration rate and effective renal plasma flow were also not significantly affected by castration. However, castration significantly reduced protein excretion in LP males to levels not different from those in NP CAS and intact males. Renal histopathology scores showed a similar pattern. Thus removal of androgens by castration failed to provide any protective effect against the hypertension programmed by maternal protein restriction. Castration also failed to abolish the sex difference in blood pressure in both diet groups. These findings suggest that the lifelong presence of normal levels of testicular hormones does not play a major role either in maintaining baseline blood pressure higher in males than in females, or in promoting further elevations in blood pressure in males due to prenatal undernutrition. However, androgens such as testosterone may promote renal injury in LP males. dietary protein restriction; sexual dimorphism; glomerular filtration rate.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume298
Issue number4
DOIs
StatePublished - Apr 2010

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Castration
Hypertension
Sex Characteristics
Diet
Blood Pressure
Proteins
Glomerular Filtration Rate
Kidney
Androgens
Testosterone
Testicular Hormones
Effective Renal Plasma Flow
Pregnancy
Dietary Proteins
Malnutrition
Arterial Pressure
Mothers

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Cite this

Castration fails to prevent prenatally programmed hypertension in male rats. / Woods, Lori L.; Morgan, Terry; Resko, John A.

In: American Journal of Physiology - Regulatory Integrative and Comparative Physiology, Vol. 298, No. 4, 04.2010.

Research output: Contribution to journalArticle

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