Nefazodone Alters NPY Immunostaining in Rat Arcuate-paraventricular Projection without Changes in Food Intake and Body Weight

Abstract

Nefazodone is an antidepressant drug that inhibits serotonin and noradrenaline reuptake. The aim of the present work was to study the effects of nefazodone on food intake, body weight, adiposity and hypothalamic NPY immunostaining in rats. For this purpose, male Sprague-Dawley rats (3-month-old) were administered with nefazodone (20 mg/kg; i.p) daily for two weeks. The control group was given 0.9% NaCl solution. Hypothalamic arcuate, paraventricular, periventricular, supraoptic and suprachiasmatic nuclei and the lateral hypothalamic area were immunostained for NPY. Chronic nefazodone administration in rats did not modify food intake, body weight and adipose depot size (subcutaneous, perirenal and epididymal white adipose tissues, and interscapular brown adipose tissue). However, a significant decrease in paraventricular NPY immunostaining was found in the nefazodone group compared with the control group. No changes in other hypothalamic regions such as arcuate, periventricular, supraoptic and suprachiasmatic nuclei, and lateral and medial preoptic areas were observed. Because nefazodone is an alpha1-adrenoceptor antagonist, it can be proposed that the expected decrease in food intake after nefazodone administration, due to its effects on NPY arcuate-paraventricular projection, could be masked by the opposite orexigenic effect of alpha1-adrenoceptor blockade.

Effect of Crude Saponin of Korean Red Ginseng on High-Fat Diet-Induced Obesity in the Rat

“…This suggestion is strengthened by the report of Dryden et al (52) who reported that treatment with fluoxetine, a specific serotonin reuptake inhibitor, reduced NPY concentrations in the PVN without changes of mRNA levels in the ARC. Another study also reported that a significant decrease in NPY immunostaining in the PVN, but not in the arcuate or suprachiasmatic nuclei, was observed after treatment with nefazodone, serotonin, and noradrenaline reuptake inhibitor (53). Accordingly, our results suggest that the anorexigenic effect of CS in HF diet-induced obese rats may be, in part, mediated through the NPY ARC-PVN projection.…”

Effects of prenatal exposure to fluoxetine on circadian rhythmicity in the locomotor activity and neuropeptide Y and 5‐HT expression in male and female adult Wistar rats

“…In addition to the effect of 5‐HT on the firing rate, it is known that modulation of 5‐HT and NPY itself can affect SCN function (Palus et al, 2013; Smith et al, 2015). For example, previous studies have shown that chronic SSRIs administration in adult male rats induces a reduction in NPY expression in the paraventricular nucleus and lateral hypothalamic area but not in the SCN specifically (Gutiérrez et al, 2002; Saracíbar et al, 2002). Furthermore, Ugrumov et al (1994) showed that the treatment with serotonergic agonists modulates the differentiation of peptidergic neurons in SCN, even before the establishment of afferent inputs from RN during the prenatal development period.…”