Expression analysis of neuropeptide FF receptors on neuroendocrine-related neurons in the rat brain using highly sensitive in situ hybridization

Central Kisspeptin Does Not Affect ERK1/2 or p38 Phosphorylation in Oxytocin Neurons of Late-Pregnant Rats

“…To determine whether ICV kisspeptin activates organum vasculosum of the lamina terminalis (OVLT), median preoptic nucleus (MnPO) and/or subfornical organ (SFO) neurons, which each project to the SON and PVN [ 33 , 34 , 35 ] and express Kiss1R and/or NPFFR [ 25 , 27 , 30 , 36 ], pERK1/2 and p-p38 were labelled in each brain area.…”

“…Although our recent findings showed that kisspeptin excites oxytocin neurons in late pregnancy, in part, by a direct action of kisspeptin on oxytocin neurons, our findings also suggested that activation of afferent inputs might also contribute to the excitation [ 9 ]. Therefore, we mapped kisspeptin-induced ERK1/2 and p38 phosphorylation in brain areas that project to the oxytocin system and express Kiss1R and NPFFR (LC, DRN, OVLT, SFO, AVPe, ARC) [ 25 , 27 , 30 , 36 ], only NPFFR (NTS, PeN) [ 36 ] or only Kiss1R (RVLM, MnPO) [ 25 , 51 ]. However, neither ERK1/2 nor p38 phosphorylation was affected by kisspeptin in any of the brain areas studied in non-pregnant or late-pregnant rats.…”

“…Mean (± SEM) numbe 2.6. Kisspeptin Does Not Affect pERK1/2 or p-p38 Expression in the AVPe, PeN or pERK1/2 Expression in the ARC pERK1/2 and p-p38 were also labelled in the anteroventral periventricular nucleus (AVPe), periventricular nucleus (PeN) and arcuate nucleus (ARC), which contain kisspeptin neurons [37,38], express Kiss1R and/or NPFFR [25,30,36]. Kisspeptin PeN neurons project to the SON but AVPe and ARC kisspeptin neurons do not [8].…”

NPFF Decreases Activity of Human Arcuate NPY Neurons: A Study in Embryonic-Stem-Cell-Derived Model

“…However, NPFF has a higher affinity and potency for NPFFR2 [ 10 , 11 , 12 ]. While NPFFR1 is ubiquitously expressed in the CNS and has been associated with regulation of stress response and reproduction [ 12 , 13 , 14 , 15 , 16 ], NPFFR2 is expressed in distinct brain regions and neurons, including the neuropeptide Y (NPY) neurons of the arcuate nucleus (ARC) of the hypothalamus, positioning NPFFR2+ NPY neurons to play a key role in food intake, appetite modulation and overall, in metabolism [ 6 , 16 ]. In addition, NPFFR2 is expressed in the paraventricular nucleus of the hypothalamus (PVN) and at low levels in the superficial layers of the spinal cord and thalamic nuclei [ 11 , 16 , 17 , 18 ].…”

“…Thus, applying a Gi agonist such as NPFF to inhibit ARC NPY neurons would dis-inhibit PVN CRH neurons [ 19 , 20 , 21 ]. Accordingly, the NPFFR2-mediated effect of NPFF on food intake and energy balance is believed to be due to increased neuronal activity in the PVN, modulating signaling along the hypothalamo–pituitary–adrenal (HPA) axis and the autonomic nervous system [ 6 , 16 , 22 , 23 ]. As shown in in vivo mouse studies, an intracerebroventricular (i.c.v.)…”