Implication of central neurohypophyseal hormone receptor-mediated action in timing of reproductive events: evidence from novel observations on the effect of a vasotocin analogue on singing behaviour of the canary.

A highly discrete distribution of neurohypophyseal hormone receptors was discovered in the mammalian and avian brain. These receptors are heterogeneous. In rat brain oxytocin (OT) and V1a receptors can be distinguished which bind OT with an order of magnitude difference in affinity and which are located in discrete sites of the limbic-midbrain circuitry.

Localization of interleukin 6 mRNA and interleukin 6 receptor mRNA in rat brain.

The cytokine interleukin 6 (IL6) has several effects on the central nervous system in addition to the well established regulation of the acute phase inflammatory response. Therefore, the distribution of IL6- and IL6 receptor mRNA in the rat brain has been investigated by in situ hybridization using [35S]-labeled oligonucleotides. The messages of both genes were found in the CA1-CA4 regions as well as in the dentate gyrus of the hippocampus, in the habenulae, the dorsomedial and the ventromedial hypothalamus, in the internal capsule, the optic tract and in the piriform cortex.

Plasticity and function of brain corticosteroid receptors during aging.

The actions of adrenal corticosteroids on the brain are critical for the maintenance of homeostasis. These actions are mediated by two receptors: mineralocorticoid (MRs) and glucocorticoid receptors (GRs), which are co-localized in hippocampal neurons. Our research has shown that MR- and GR-mediated effects restore disturbances in homeostasis, but they do so via an opposite mode of action.

Oxytocin gene expression in discrete hypothalamic magnocellular cell groups is stimulated by prolonged salt loading.

The effect of prolonged osmotic stimulation on the oxytocin (OT) mRNA levels of OT-producing neurons was investigated in separate hypothalamic nuclei of the rat. After drinking 2% NaCl for 2 weeks, a 2-fold increase in the OT mRNA content was found by Northern blot analysis of microdissected supraoptic nucleus (SON) and paraventricular nucleus (PVN). The same samples showed a similar change in vasopressin (VP) mRNA levels.

Estradiol modulates density of putative 'oxytocin receptors' in discrete rat brain regions.

Previous studies have provided evidence for a discrete localization of two types of vasopressin (AVP)-labeled binding sites in the rat brain, i.e., regions labeled preferentially with AVP (putative AVP receptors) and regions labeled with AVP as well as oxytocin (OT).