Hemicastration in the rat is followed by hypertrophy of the remaining gonad (Heller, Heller & Sevringhaus, 1942), presumably as a result of increased pituitary secretion of gonadotrophins (Benson, Sorrentino & Evens, 1969). Howland (1972) recently demonstrated that caloric restriction interfered with ovarian hypertrophy and speculated that this was due to a decreased level of hypothalamic releasing factors. The present study was undertaken to determine if caloric restriction affected gonadal hypertrophy in the male as in the female.
Immature Sprague-Dawley male rats, weighing 35 to 40 g, were used since the mature male does not respond with gonadal hypertrophy when hemicastrated (Means & Hall, 1967). For comparison with the results obtained by Howland (1972), adult female rats weighing 160 to 180 g were used, but for comparison with the males, an immature female was used. Both sexes were