Stimulation of Gastric Acid Secretion by Centrally Administered Orexin-A in Conscious Rats

Requirement of Intact Disulfide Bonds in Orexin-A-Induced Stimulation of Gastric Acid Secretion That Is Mediated by OX1 Receptor Activation

“…In addition to these functions, we have shown that intracisternal but not intraperitoneal injection of orexin-A dosedespondently stimulated gastric acid secretion in conscious rats (11). The acid stimulation by central orexin-A was completely blocked by atropine or surgical vagotomy, suggesting that orexin-A acts in the brain to stimulate gastric acid secretion through the vagal system.…”

“…Gastric acid secretion was measured using the pylorus-ligation method as described previously (11,13). Rats received intracisternal injection of orexin-A, orexin-B, orexin-A (15-33) or orexin-A analogues in a dose of 10 µg/10 µl.…”

“…Rats received intracisternal injection of orexin-A, orexin-B, orexin-A (15-33) or orexin-A analogues in a dose of 10 µg/10 µl. The doses used in this study were basically selected according to our previous study (11). Control animals were injected with normal saline (10 µl (Fig.…”

Distribution of orexinergic neurons and their terminal networks in the brains of two species of African mole rats

“…Orexin (also known as hypocretin) is a neuropeptide that has been reported to play a role in the regulation of feeding, drinking, body temperature, general activity (Lubkin and Stricker-Krongrad, 1998;Edwards et al, 1999;Hagan et al, 1999;Kunii et al, 1999;Mondal et al, 1999;Piper et al, 2000;Estabrooke et al, 2001;Hungs et al, 2001;Yoshimichi et al, 2001;Kotz et al, 2002;Berthoud et al, 2005), energy homeostasis (Mintz et al, 2001), stimulation of gastric secretion in rats (Takahashi et al, 1999), increasing metabolic rate in rats (Lubkin and Stricker-Krongard, 1998), altering luteinising hormone release in rats (Pu et al, 1998) and in the regulation of the sleepwake cycle specifically associated with increased wakefulness and inhibition of REM sleep (Sakurai et al, 1998;Chemelli et al, 1999;Siegel, 1999;Bourgin et al, 2000;Kilduff and Peyron, 2000;Thannickal et al, 2000;van den Pol, 2000).…”

Endogenous orexin-A in the brain mediates 2-deoxy-d-glucose-induced stimulation of gastric motility in freely moving conscious rats

“…According to in vitro binding and functional assays, OX1R is selective for orexin-A and OX2R is non-selective for orexin-A and -B [2]. The effect of intracisternal (ic) injection of orexin-A or -B on gastric acid secretion was examined and it was clearly demonstrated that the acid stimulation was induced by orexin-A but not orexin-B [11], suggesting orexin-A-induced stimulation of gastric functions may be mediated by OX1R. non-fasted conscious rats [13].…”