GONADAL-HORMONES STIMULATE ULTRASOUND PRODUCTION BY FEMALE HAMSTERS

Two studies were conducted to examine the role of sex hormones in ultrasound production by female hamsters. Ovariectomized hamsters were treated with estradiol benzoate (EB), testosterone propionate (TP), progesterone (P), estradiol plus progesterone (EB + P), testosterone plus progesterone (TP+P), or oil vehicle. Rates of ultrasound production by these females were observed in response to brief male-female contact, and during exposure to synthetic ultrasounds. Maximal rates of ultrasound production required EB + P or TP+P replacement therapy. Intermediate call rates were stimulated by EB and TP individually, whereas P alone had no significant effect. These results support the hypothesis that ovarian estrogens and progesterone control proceptive as well as receptive behaviors in female hamsters. © 1979.