Ceruletide suppresses endogenous dopamine release via vagal afferent system, studied by in vivo intracerebral dialysis

Changes in GABA content and turnover in discrete regions of rat brain after systemic administration of caerulein

“…1978;Bunney 1979, 1985;Scheel-Kriiger et al 1980;Waszczak et al 1980). In support of our findings, peripherally administered caerulein has been reported to reduce endogenous dopamine release in the striatum (Hamamura et al 1989). Hommer et al (1985) have reported that CCK has an excitatory action on neural firing rate in the substantia nigra following peripheral administration.…”

Epinephrine potentiates antipsychotic, but not cataleptogenic effect of haloperidol in rats

“…Cholecystokinin is a peripheral antipsychotic reducing dopamine release in the striatum as a result of CCK A receptor stimulation in the subdiaphragmatic gastric vagus afferents [6,12]; in low doses this agent potentiates the antipsychotic effect of haloperidol, but not its extrapyramidal effects [7,10]. However, CCK is not widely used in clinical practice because of complex technology of manufacture of its dosage form and pronounced anxiogenic and prodepressant effects [4].…”

“…In contrast to haloperidol, cholecystokinin (CCK) reducing dopamine release in the striatum as a result of CCK A receptor stimulation in the subdiaphragmatic gastric vagus afferents, is a peripheral antipsychotic causing no extrapyramidal disorders even in high doses [4,6,12]. Combined use of haloperidol and CCK potentiates their antipsychotic effects and attenuates extrapyramidal disorders due to reduction of haloperidol dose [7,10].…”

Ceruletide, an Analog of Cholecystokinin Octapeptide: New Perspectives on Its Efficacy

“…5, No. 2, 1999 CERULETIDE 147 was reported to antagonize some of the behavioral and neurochemical effects of ceruletide (21,23,43,98), the vagal afferent pathway to the nucleus tractus solitarii has been considered to be the major site of the central actions of peripherally administered ceruletide (11). It is, however, unlikely that all the effects of ceruletide might be attributed to the actions on the vagal nerves in the visceral organs (22,63).…”

“…One study reported that ceruletide decreased basal dopamine release in the striatum, and this effect was blocked by a subdiaphragmatic vagotomy (23). However, other studies reported that ceruletide had no effect on basal dopamine release in the striatum but decreased haloperidol-induced dopamine release under the high K + concentrations in the perfusate (41).…”