Previous studies in Wistar rats suggest inter-individual differences in anxiety-like behaviour as assessed using the elevated plus maze (EPM), both between sexes and among males, to be abolished by serotonin depletion. To shed further light on the influence of sex steroids and serotonin - and on the interplay between the two - on proneness for EPM-assessed anxiety in males, outbred Wistar rats ...

In mammals, it is well established that circadian rhythms in physiology and behavior, including the rhythmic secretion of hormones, are regulated by a brain clock located in the suprachiasmatic nucleus (SCN) of the hypothalamus. While SCN regulation of gonadal hormone secretion has been amply studied, the mechanisms whereby steroid hormones affect circadian functions are less well known. This i...

Hyperinsulinemia and insulin resistance are closely associated with hypertension in humans and in animal models. Gender differences have been found in the development of hypertension in fructose-fed rats. The objectives of the present study were, first, to clarify whether androgens are required in the development of hyperinsulinemia, insulin resistance, and hypertension in fructose-fed rats, an...

Deletion of the distal segment of 9p causes a syndrome comprising trigonocephaly, minor anomalies, and intellectual disability. Patients with this condition also frequently present with genitourinary abnormalities including cryptorchidism, hypospadias, ambiguous genitalia, or 46,XY testicular dysgenesis. The region responsible for the gonadal dysgenesis has been localized to 9p24.3 with the lik...

We decreased the level of gonadal steroids in female and male mice by gonadectomy. We infected these mice with P. berghei ANKA and observed the subsequent impact on the oxidative stress response. Intact females developed lower levels of parasitaemia and lost weight faster than intact males. Gonadectomised female mice displayed increased levels of parasitaemia, increased body mass, and increased...

Blood collections were taken every 20 min over 12 h on 6 occasions within 1 month before and after gonadectomy of 5 cyclic and 5 post-partum dairy cows and again on one occasion 3--5 months thereafter. By 4 days after ovariectomy of the cyclic cows (i.e. 4 days after oestrus) average plasma LH values and the frequency and amplitude of pulsatile LH release had increased about 3-fold. In the cows...

Experiments examined activational roles of gonadal steroids on the sexually dimorphic, calcitonin gene-related peptide-expressing neurons of the rat preoptic area. Gonadectomy of male rats followed by treatment with testosterone, dihydrotestosterone, or estrogen demonstrated that the tonic suppressive influence of testosterone on cellular levels of calcitonin gene-related peptide mRNA expressio...

T. lewisi infection in normal adult 3 month old albino rats raised from a single stock and maintained under identical conditions was studied. Daily quantitative estimates of the trypanosomes in the circulating blood were made and the course of the infection was studied. Bilateral suprarenalectomy in rats lowers the resistance to a subsequent infection with T. lewisi. About 70 per cent of these ...

introduction: effective perception of fear signals is crucial for organism survival. when threated, the organism indicates defensive behaviors. methods: elevated plus–maze has high efficiency for measurement of fear behavior and is widly used for fear behavior determination. increase in two parameters percent of openarm entries (%oae) and percent of time spent in the open-arm (%oat) in the elev...