Hindbrain noradrenergic lesions attenuate anorexia and alter central cFos expression in rats after gastric viscerosensory stimulation.

نویسنده

  • Linda Rinaman
چکیده

Behavioral, autonomic, and endocrine outputs of the CNS are subject to important feedback modulation by viscerosensory signals that are conveyed initially to the hindbrain nucleus of the solitary tract (NST). In the present study, noradrenergic (NA) neurons [i.e., those that express the NA synthetic enzyme dopamine beta hydroxylase (DbH)] in the caudal NST were lesioned to determine their role in mediating anorexic responses to gastric stimulation and in conveying gastric sensory signals to the hypothalamus and amygdala. For this purpose, saporin toxin conjugated to an antibody against DbH was microinjected bilaterally into the caudal NST in adult rats. Control rats received similar microinjections of vehicle. Several weeks later, rats were tested for the ability of systemic cholecystokinin octapeptide (CCK) (0 or 10 microg/kg) to inhibit food intake. CCK-induced anorexia was significantly attenuated in toxin-treated rats. Rats subsequently were used in a terminal cFos study to determine central neural activation patterns after systemic CCK or vehicle and to evaluate lesion extent. Toxin-induced loss of DbH-positive NST neurons was positively correlated with loss of CCK-induced anorexia. Hypothalamic cFos expression was markedly attenuated in lesioned rats after CCK treatment, whereas CCK-induced neural activation in the parabrachial nucleus and amygdala appeared normal. These findings suggest that hindbrain NA neurons are an integral component of brainstem circuits that mediate CCK-induced anorexia and also are necessary for hypothalamic but not parabrachial or amygdala responses to gastric sensory stimulation.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Trimethylthiazoline (TMT) supports conditioned flavor avoidance and activates viscerosensory, hypothalamic, and limbic circuits in rats

Interoceptive stimuli modulate stress responses and emotional state, in part, via ascending viscerosensory inputs to the hypothalamus and limbic forebrain. It is unclear whether similar viscerosensory pathways are recruited by emotionally salient exteroceptive stimuli, such as odors. To address this question, we investigated conditioned avoidance and central cFos activation patterns in rats exp...

متن کامل

Changes in the gastric ghrelin concentration after whole-abdominal irradiation in rats: Is this related to the radiation-induced anorexia and weight loss?

Background: Ghrelin is a hormone related to food intake in rodents and humans, mainly produced in stomach. This study aimed to determine the effect of irradiation on ghrelin concentration in the gastric mucosa of rats. Materials and Methods : Twenty-five rats were exposed to 15 Gy of whole-abdominal irradiation. Gastric tissue samples were obtained 1, 3, 7, 30, and 90 days after irradiation. Fi...

متن کامل

Hindbrain contributions to anorexia.

FEEDING BEHAVIOR is the complex functional output of distributed neural networks, with critical components located at every level of the central neuraxis (1, 20). Nevertheless, the ability of any internal or external factor to modulate food intake ultimately depends on its ability to affect hindbrain neural circuits that control ingestive motor output. In this regard, anatomical, physiological,...

متن کامل

The effects of locus coeruleus electrical stimulation on brain waves of morphine dependent rats

Introduction: Opiates cause dependency via affect on central nervous system. Locus coeruleus nucleus is a main group of noradrenergic neurons in the brain that plays an important role in the expression of opioid withdrawal signs. During opioid withdrawal, brain waves change in addition to physical and behavioral signs. In this study, we examined the effects of locus coeruleus electrical sti...

متن کامل

Role of the locus ceruleus in baroreceptor regulation of supraoptic vasopressin neurons in the rat.

The goal of this study was to identify the source of baroreceptor-related noradrenergic innervation of the diagonal band of Broca (DBB). Male Sprague-Dawley rats underwent sinoaortic denervation (SAD, n = 13) or sham SAD surgery (n = 13). We examined Fos expression produced by baroreceptor activation and dopamine-beta-hydroxylase immunofluorescence in hindbrain regions that contain noradrenergi...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • The Journal of neuroscience : the official journal of the Society for Neuroscience

دوره 23 31  شماره 

صفحات  -

تاریخ انتشار 2003