Enhancement of the sensitivity of hamster check pouch arterioles to beta-adrenergic stimulus during pregnancy.

The adrenergic beta stimulant fenoterol induced a dose-dependent vasodilatation of hamster cheek pouch arterioles. The response to fenoterol was significantly larger on day 14 of pregnancy than in metoestrous animals. Since the serum progesterone and 17 beta-oestradiol level were also elevated on day 14, a relationship was suggested between the enhancement of vascular sensitivity and sex-steroid hormone levels.