Circadian rhythm of corticosterone secretion in the neonatal rabbit.

Maternal care in the rabbit is restricted to a single 3- to 5-min period of nursing each day. One to three hours prior to the arrival of the mother, pups exhibit anticipatory behavioral arousal and elevation of core body temperature. In rodents, the hypothalamic-pituitary-adrenal axis is quiescent and levels of the adrenal hormone, corticosterone (CORT), are stable and extremely low during the first days of life, which are known collectively as the stress-hyporesponsive period (SHRP).

Immunocytochemical detection of progesterone receptor in the female rabbit forebrain: distribution and regulation by oestradiol and progesterone.

There is no information on the neuroanatomical distribution of the progesterone receptor (PR) in the rabbit. Therefore, we mapped the distribution of PR-immunoreactive cells in the forebrain of ovariectomized female rabbits. Vehicle-injected ovariectomized rabbits showed PR-immunoreactive cells only in the infundibular nucleus (IN) and nucleus X (lateral to the ventromedial hypothalamic nucleus).

Suckling and genital stroking induces Fos expression in hypothalamic oxytocinergic neurons of rabbit pups.

Maternal behaviour in the rabbit is unusual among mammals because the doe visits her litter to nurse once every 24 h. In the present study we examined the consequences of milk intake on oxytocinergic (OT) and vasopressinergic (AVP) neurons of the supraoptic (SON) and paraventricular (PVN) nuclei of 7-day-old pups before suckling, after suckling and following anogenital stroking in un-nursed pups. To determine neuronal activation we assessed the expression of the Fos protein combined with antibodies against OT and AVP at two levels in the SON (supraoptic rostral, SOr, and supraoptic retrochiasmatic, SOrch), and three levels in the PVN (anterior, PVab; medial PVm and caudal, PVc).

[Percutaneous pulmonary valvulotomy using radiofrequency in pulmonary atresia with intact interventricular septum].

Early pulmonary valvulotomy in patients with pulmonary atresia and intact interventricular septum allows the development and growth of the right ventricle and two-ventricle circulation. Percutaneous valvulotomy today is a valid alternative procedure to surgical valvulotomy. With the use of the radiofrequency 5F currently available for the treatment of arrythmias atretic pulmonary valve perforation and consecutive balloon dilation may be safely and effectively performed.