Vascular reactions to cold in the cheek pouch of intact and adrenalectomized hamsters

¹ Department of Biology, Boston University, Boston, Massachusetts

Adrenalectomized golden hamsters unanesthetized or under anesthesia, did not maintain body temperature when exposed to environmental cold (2°C) as well as intact hamsters or adrenalectomized hamsters receiving cortisone replacement therapy. Dial with urethane anesthesia proved unsuitable for studies of microcirculation in cold so light ether anesthesia was used. At room temperature there were no significant changes in caliber of small vessels of intact or adrenalectomized hamsters under ether, but arteries of hamsters receiving replacement therapy constricted. Suitable controls showed that this was partly due to the treatment. During 2 hours in cold air there was significant constriction of arteries of intact and of adrenalectomized hamsters receiving replacement therapy, but no change in veins, while the majority of untreated adrenalectomized hamsters showed no significant changes in the arteries. This is interpreted as an impairment of the normal peripheral vasoconstrictor response to cold which can be restored by replacement therapy.