During puberty, humans develop a later chronotype, exhibiting a phase-delayed daily rest/activity rhythm. The purpose of this study was to determine: 1) whether similar changes in chronotype occur during puberty in a laboratory rodent species, 2) whether these changes are due to pubertal hormones affecting the circadian timekeeping system. We tracked the phasing and distribution of wheel-runnin...

Pak TR, Chung WC, Hinds LR, Handa RJ. Arginine vasopressin regulation in preand postpubertal male rats by the androgen metabolite 3 -diol. Am J Physiol Endocrinol Metab 296: E1409–E1413, 2009. First published April 21, 2009; doi:10.1152/ajpendo.00037.2009.—Arginine vasopressin (AVP) is a nonapeptide expressed in several brain regions. In addition to its well-characterized role in osmoregulation...

Some laboratories have reported sex differences in the effect of estrogen priming on neural progestin receptor concentration, whereas others find no such differences. The present studies sought to identify experimental variables which might differentially influence the measurable level of hypothalamic cytosol progestin receptors in adult male and female rats. The influence of three variables, b...

Exposure of newborn and infant mice to urethan results in a significantly higher incidence of hepatomas in male mice than in females. Sex of the animals, however, does not influence the development of malignant lymphomas, Harderian gland tumors, and lung adenomas. In the present study, the role of gonads in the development of urethan-induced hepatomas and other tumors has been investigated. Sev...

The distribution of vasopressin-immunoreactive fibers in the forebrain of male and female gerbils was studied, focusing on the lateral septum and the sexually dimorphic area (SDA) found at the border between the medial preoptic area and the anterior hypothalamus. To study hormonal influences on the densities of these fibers, some animals of each sex were gonadectomized or gonadectomized and giv...