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Immunoreactive Neurones (immunoreactive + neurone)
Selected AbstractsLocus Coeruleus Norepinephrine Regulates the Surge of Prolactin During OestrusJOURNAL OF NEUROENDOCRINOLOGY, Issue 10 2005R. E. Szawka Abstract A secondary surge of prolactin has been recently characterised on the afternoon of oestrus. Because the noradrenergic nucleus locus coeruleus participates in the genesis of the pro-oestrous and steroid-induced surges of prolactin, the aim of the present study was to investigate the importance of locus coeruleus norepinephrine in the generation of the prolactin surge of oestrus. For this purpose, we initially re-evaluated the profile of prolactin secretion during the oestrous cycle to verify whether this surge of prolactin was physiological and specific to the day of oestrus. Thereafter, the following were evaluated: (i) the effect of locus coeruleus lesion on the secondary surge of prolactin and on norepinephrine concentration in the medial preoptic area (MPOA), medial basal hypothalamus (MBH) and paraventricular nucleus (PVN) during the day of oestrus and (ii) locus coeruleus neurones activity during the same day by Fos immunoreactivity. Locus coeruleus lesion completely blocked the prolactin surge of oestrus in all rats studied and also significantly reduced norepinephrine concentration in the MPOA, MBH and PVN during the day of oestrus. The number of double-labelled tyrosine hydroxylase/Fos immunoreactive neurones in locus coeruleus was significantly higher at 14.00 h of oestrus, suggesting an increase in its activity preceding the prolactin surge that generally occurs at 15.00 h. Therefore, the increase in locus coeruleus activity on the afternoon of oestrus supports the data obtained with bilateral lesion of this nucleus, suggesting a stimulatory role of locus coeruleus norepinephrine in the genesis of the secondary surge of prolactin. [source] Long-Term Undernutrition Followed by Short-Term Refeeding Effects on the Corticotropin-Releasing Hormone Containing Neurones in the Paraventricular Nucleus: An Immunohistochemical Study in SheepJOURNAL OF NEUROENDOCRINOLOGY, Issue 4 2002E. Chaillou Abstract The effect of nutritional level on the immunoreactivity of corticotropin-releasing hormone (CRH) in neurones of the hypothalamic paraventricular nucleus was described in sheep, a ruminant, whose feeding strategy differs from that of monogastric species. Two groups of ewes were underfed (40%), or fed at maintenance (100%) for 167 days, after which one-half of each group was killed or ad libitum refed (at least 150% of maintenance) for 4 days before killing. The presence of CRH in the paraventricular nucleus was examined by immunohistochemistry. The number of CRH immunoreactive neurones was increased in underfed ewes, but without modification of the plasma concentration of cortisol, indicating that the rise of CRH was not released in the portal blood nor linked to the pituitary-adrenal axis. Refeeding did not modify significantly the number of CRH immunoreactive neurones in the nucleus although these neurones were increased, only in refed ewes that were previously underfed. These data differ from those for rats and mice where CRH expression is decreased or not modified by underfeeding which could reflect different effects of undernutrition on CRH immunoreactive neurones in monogastric compared to ruminants species. [source] Expression of c-Fos protein in the trigeminal nuclear complex resulting from quantified force application to the rat molarJOURNAL OF ORAL REHABILITATION, Issue 11 2003M. Watanabe summary, This study was conducted to investigate the expression and distribution of c-Fos-like immunoreactive neurones (Fos-neurones), in the rat trigeminal sensory nuclear complex, produced by mechanical forces with various magnitudes and durations applied to the left upper first molar. The magnitudes of forces applied to the tooth were 25, 50 and 100 g and the duration was 2 h. A quantified force of 100 g was also applied to the upper molar for varying durations [short-time (1,2 min)], 2, 4, 8 and 12 h. Fos-neurones distributed in the bilateral superficial laminae of the subnucleus caudalis, and the ipsilateral dorsomedial part of subnucleus oralis (Sp5Odm). The number of Fos-neurones increased in the subnucleus caudalis (Sp5C) according to the force magnitude. In the Sp5C, the number of Fos-neurones exhibited maximum level, 2 or 4 h after the application. In the Sp5Odm, however, the number of Fos-neurones reached the maximum level at 8 h. These data suggest that the change in the number of nociceptive neurones in Sp5C reflect changes in encoding the magnitude of force to tooth, and that the nature of pain response to orthodontic forces might have some relation to the delayed expression of c-Fos protein in the Sp5Odm. [source] Morphological Characteristics of C1 and C2 Adrenergic Neurone Groups in Marmoset Monkey Brainstem by using Antibody against Phenylethanolamine-N-methyltransferaseANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 6 2002Y.-G. Jeong Summary This work describes a mapping study of phenylethanolamine-N-methyltransferase (PNMT) immunoreactive neurones and fibres in the medulla oblongata of the marmoset monkey, Callithrix jacchus. Two groups of PNMT-immunoreactive neurones were found in the marmoset monkey medulla oblongata: a ventrolateral (C1 group) and a dorsomedial PNMT-immunoreactive cells group (C2 group). The PNMT-immunoreactive cells in the ventrolateral group C1 were found to be located around the lateral reticular nucleus. The PNMT-immunoreactive somata within the ventrolateral medulla are round to oval, and mostly multipolar with branched processes. In the dorsomedial group C2, PNMT-immunoreactive cell bodies appeared near the obex. The majority of the dorsomedial PNMT-immunoreactive neurones were observed in the nucleus tractus solitarius; although some were present in the dorsal motor nucleus of the vagus. The PNMT-immunoreactive somata in the dorsomedial medulla were small and round or ovoid. These results provide information upon the adrenergic system in the medulla oblongata of a species that presents a useful model of a small primate brain, the marmoset monkey. [source] | ||||||||||