Little is known regarding the descending inhibitory control of genital reflexes such as ejaculation and vaginal contractions. The brainstem nucleus paragigantocellularis (nPGi) projects bilaterally to the lumbosacral motoneuron pools that innervate the genital musculature of both male and female rats. Electrolytic nPGi lesions facilitate ejaculation in males, leading to the hypothesis that the ...

The preglomerular complex of trout consists of the anterior (aPGN) and medial (mPGN) preglomerular nuclei and the corpus mamillare (CM). In order to improve knowledge on this complex, we applied a lipophilic neuronal tracer (DiI) to the three nuclei. These nuclei received afferents from the medial part of the dorsal telencephalic area (Dm), the ventral part of the ventral telencephalic area (Vv...

Angiotensin II binding sites were localized and quantified in individual brain nuclei from single rats by incubation of tissue sections with 1 nM 125I-[Sar1]-angiotensin II, [3H]-Ultrofilm autoradiography, computerized microdensitometry and comparison with 125I-standards. High angiotensin II binding was present in the circumventricular organs (organon vasculosum laminae terminalis, organon subf...

The neurotransmitter serotonin (5-HT) has been suggested to be involved in the inhibition of socially regulated sex change in fish because of its role in the modulation of both reproductive and aggressive behavior. This is the first study looking at the distribution of serotonergic neurons by immunohistochemical techniques at different times during sex change. We set up stable social groups wit...

The distribution of thalamic projection neurons to the Wulst was examined in the Japanese quail (Coturnix coturnix japonica) using the retrograde transport of wheat germ agglutinin conjugated horseradish peroxidase (WGA-HRP) method. After injection of WGA-HRP into the unilateral Wulst, retrogradely labeled neurons (RLneurons) were found ipsilaterally in zones A and B of the nucleus dorsolateral...

Although the earlier supposition was that the n. dorsalils superficialis (n. lateralis dorsalis) of the thalamus projected to the parietal region, more recent evidence has linked it to the posterior cingulate gyrus and possibly adjacent regions near the splenium of the corpus callosum. An afferent supply from lower levels was in more doubt, although some report had been made of cell and fibre d...

Stress increases vulnerability to psychiatric disorders, partly by affecting brain monoamine systems, such as the locus coeruleus (LC)-norepinephrine system. During stress, LC activity is coregulated by corticotropin-releasing factor (CRF) and endogenous opioids. This study identified neural circuitry that regulates LC activity of intruder rats during the resident-intruder model of social stres...