Changes in Ovarian Function and Gonadotropin and Prolactin Secretion in Aging Female Rats
In the female rat, reproductive function is characterized by several interesting features, including (1) estrous cycles and the concomitant changes in neuroendocrine function are repeated at frequent intervals (4–5 days), and (2) reproductive life represents less than one-third of the entire lifespan. Under optimal laboratory conditions, the female rat may have a lifespan of about three years. Puberty occurs around 35–40 days after birth, and regular estrous cycles are usually seen in animals older than 2 months of age. Between the ages of 2–12 months, most adult females display regular estrous cycles of 4- or 5-day duration, and this cyclicity is interrupted by a persistent-diestrous phase when the rat is in gestation, postpartum lactation, or in a pseudopregnant condition.
KeywordsLuteinizing Hormone Corpus Luteum Estrous Cycle Ovarian Function Prolactin Secretion
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