I. Billig et al., Plasma hormone levels and central c-Fos expression in ferrets after systemic administration of cholecystokinin, AM J P-REG, 281(4), 2001, pp. R1243-R1255
Citations number
41
Categorie Soggetti
Physiology
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-REGULATORY INTEGRATIVE AND COMPARATIVE PHYSIOLOGY
Posterior pituitary hormone secretion and central neural expression of the
immediate-early gene product c-Fos was examined in adult ferrets after intr
avenous administration of CCK octapeptide. Pharmacological doses of CCK (1,
5, 10, or 50 mug/kg) did not induce emesis, but elicited behavioral signs
of nausea and dose-related increases in plasma vasopressin (AVP) levels wit
hout significant increases in plasma oxytocin (OT) levels. CCK activated ne
uronal c-Fos expression in several brain stem viscerosensory regions, inclu
ding a dose-related activation of neurons in the dorsal vagal complex (DVC)
. Activated brain stem neurons included catecholaminergic and glucagon-like
peptide-1-positive cells in the DVC and ventrolateral medulla. In the fore
brain, activated neurons were prevalent in the paraventricular and supraopt
ic nuclei of the hypothalamus and also were observed in the central nucleus
of the amygdala and bed nucleus of the stria terminalis. Activated hypotha
lamic neurons included cells that were immunoreactive for AVP, OT, and cort
icotropin-releasing factor. Comparable patterns of brain stem and forebrain
c-Fos activation were observed in ferrets after intraperitoneal injection
of lithium chloride (LiCl; 86 mg/kg), a classic emetic agent. However, LiCl
activated more neurons in the area postrema and fewer neurons in the nucle
us of the solitary tract compared with CCK. Together with results from prev
ious studies in rodents, our findings support the view that nauseogenic tre
atments activate similar central neural circuits in emetic and nonemetic sp
ecies, despite differences in treatment-induced emesis and pituitary hormon
e secretion.